The Connecticut Quaternary Geology digital spatial data combines the information portrayed on the on-land portion of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin (Stone and others 2005) with the information portrayed on its sister map, the Surficial Materials Map of Connecticut (Stone and others, 1992). When used together, these maps provide a three dimensional context for understanding and predicting the internal composition, resource potential and hydrologic character of Connecticut's glacial and postglacial deposits. Both were compiled at 1:24,000 scale, and published at 1:125,000 scale. The Quaternary Geologic Map of Connecticut and Long Island Sound Basin (Stone and others, 2005) portrays the glacial and postglacial deposits of Connecticut (including Long Island Sound) with an emphasis on where and how they were emplaced. Glacial Ice-Laid Deposits (thin till, thick till, and deposits of individual end moraines), Early Postglacial Deposits (Late Wisconsinan to Early Holocene stream terrace and inland dune deposits) and Holocene Postglacial Deposits (alluvium, swamp deposits, marsh deposits, beach and dune deposits, talus, and artificial fill) are differentiated from Glacial Meltwater Deposits. This mapping is based on the concept of systematic northward retreat of the Late Wisconsinan glacier. Meltwater deposits are divided into six depositional system categories (Deposits of Major Ice-Dammed Lakes, Deposits of Major Sediment-Dammed Lakes, Deposits of Related Series of Ice-Dammed Ponds, Deposits of Related Series of Sediment-Dammed Ponds, Deposits of Proximal Meltwater Streams, and Deposits of Distal Meltwater Streams) based on the arrangement and character of the groupings of sedimentary facies (morphosequences). The Surficial Materials Map of Connecticut (Stone and others, 1992) portrays the glacial and postglacial deposits of Connecticut in terms of their aerial extent and subsurface textural relationships. Glacial Ice-Laid Deposits (thin till, thick till, end moraine deposits) and Postglacial Deposits (alluvium, swamp deposits, marsh deposits, beach deposits, talus, and artificial fill) are differentiated from Glacial Meltwater Deposits. The meltwater deposits are further characterized using four texturally-based map units (g = gravel, sg = sand and gravel, s = sand, and f = fines). In many places a single map unit (e.g. sand) is sufficient to describe the entire meltwater section. Where more complex stratigraphic relationships exist, "stacked" map units are used to characterize the subsurface (e.g. sg/s/f - sand and gravel overlying sand overlying fines). Where postglacial deposits overlie meltwater deposits, this relationship is also described (e.g. alluvium overlying sand). Map unit definitions (Surficial Materials Polygon Code definitions, found in the metadata) provide a short description of the inferred depositional environment for each of the glacial meltwater map units. The geologic contacts between till and meltwater deposits coincide on both the Quaternary and Surficial Materials maps, as do the boundaries of polygons that define areas of thick till, alluvium, swamp deposits, marsh deposits, beach and dune deposits, talus, and artificial fill. Within the meltwater deposits, a Quaternary map unit (deposit) may contain several Surficial Materials textural units (akin to facies within a delta, for example). Combining the textural and vertical stacking information from the Surficial Materials map with the orderly portrayal of morphosequence relationships, up and down valley, that can be gleaned from the Quaternary map provides a three dimensional predictive context for relating the geologic setting of Connecticut's glacial meltwater deposits to their behavior as aquifers and/or transmitters of contaminants. Since this data layer is a polygon and line feature representation of the two maps combined, each map unit's depiction and description could provide information as to its aerial extent, subsurface textural characteristics, depositional and paleogeographic settings, and facies composition in a morphosequence context. Therefore, a typical meltwater polygon would have a combination of Quaternary (e.g. Deposit of Major Sediment-Dammed Lake; Glacial Lake Middletown Cromwell Deltaic Deposit) and Surficial Materials (e.g. sand and gravel overlying sand overlying fine) map attributes. Additional polygon features are incorporated to define surface water areas for streams, lakes, ponds, bays, and estuaries greater than 5 acres in size. Line features describe the type of boundary between individual geologic or textural units such as a geologic contact line between two different geologic units or a linear shoreline feature between a textural unit and an adjacent waterbody. The data have been updated to reflect minor changes in map unit name (QUPOLY_COD) for consistency with the 2005 publication of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin. Previously distributed versions of CTQSGEOM were consistent with the 1998 Open-file Report for the same map. It is important to note that this data layer represents only the on-land portion of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin (Stone and others, 2005). The off-shore geologic units are organized in separate data layers (LISQMOR, LISQFAN, LISQLAKE, LISQCHAN, LISQMARD) which can be used in conjunction with this data layer. These Long Island Sound layers have been mapped at 1:80,000 scale using seismic reflection data. The CTQSGEOM data layer should be used as the geologic base for Connecticut Quaternary Geology / Surficial Materials Features (CTQSFEAT) data layer which represents features such as eskers, meltwater channels, spillways, and locations of radio-carbon dated samples.
Connecticut Quaternary Geology and Surficial Materials is 1:24,000-scale data suitable for geologic and environmental mapping and analysis purposes. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.). Not intended for analysis with other digital data compiled at scales greater than or more detailed than 1:24,000 scale. This data layer should be used as the geologic base for Connecticut Quaternary Geology / Surficial Materials Features (CTQSFEAT). The data layer can be used in conjunction with data layers representing related geologic features in the Long Island Sound Basin (LISQMOR, LISQFAN, LISQLAKE, LISQCHAN, LISQMARD).
Data manually digitized from 1:24,000-scale mylar quadrangle compilation sheets prepared for the Surficial Materials Map of Connecticut, 1:125,000 scale (Stone and others, 1992) and the Quaternary Geologic Map Of Connecticut and Long Island Sound Basin, 1:125,000 scale (Stone and others,2005). For a more complete understanding of the geologic principles behind the data it is advisable to consult these source maps which contain cross sections, diagrams and text not available in digital form. Digital files which should be used with this data set include: SIM-2784.pdf (pamphet from the Quaternary Geologic Map Of Connecticut and Long Island Sound Basin), Surficial Materials data layer, and the companion data sets: Connecticut Quaternary Geology / Surficial Materials Features (CTQSFEAT), and Long Island Sound moraines (LISQMOR), lacustrine fans (LISQFAN), lake-bottom and deltaic deposits (LISQLAKE), channel-fill deposits (LISQCHAN), and marine deltaic deposits (LISQMARD); all available for download at http://www.dep.state.ct.us/gis.
publication date
No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not recommended for use with other data layers having source map scales greater than 1:24,000 (1 inch = 2000 feet) or printed on maps at scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet). The geologic contacts are considered accurate as mapped at 1:24,000 scale. While it may be desirable to represent the geology at a larger scale for site-specific applications, keep in mind that 1:24,000-scale accuracy may not be appropriate for such uses. Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey or the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the U.S. Geological Survey and the State of Connecticut, Department of Environmental Protection as the source for this information. For example, include the following data source description when printing this layer on a map: Quaternary Geology - From the Quaternary Geology/Surficial Materials Master layer, compiled and published by the USGS and CT DEP. Source map scale is 1:24,000. The data is most relevent when used at the intended state-wide scale of 1:125,000 and in conjunction with the additional information found only on the following parent maps: Surficial Materials Map of Connecticut (Stone and others, 1992) and Quaternary Geologic Map of Connecticut and Long Island Sound Basin (Stone and others, 2005).
1080 Shennecossett Rd
Kristi LeDuc, Margaret Thomas, and Mary DiGiacomo-Cohen for designing, compiling, digitizing, and editing the Quaternary Geology and Surficial Materials data layer. Much of the production effort was undertaken by the Long Island Sound Resource Center: a partnership between the State of Connecticut, Department of Environmental Protection and the University of Connecticut Marine Sciences and Technology Center. This digital data was produced by the State of Connecticut, Department of Environmental Protection with support from the U.S. Geological Survey, the U.S. Environmental Protection Agency, and the Connecticut Department of Public Health and Addiction Services. The U.S. Geological Survey in cooperation with the State of Connecticut, Department of Environmental Protection, Geological and Natural History Survey drafted the 1:24,000-scale compilation sheets used to publish the 1:125,000-scale Surficial Materials Map of Connecticut, Stone and others, 1992 and create the 1:24,000-scale digital data.
The Quaternary Geology/Surficial Materials layer retains the feature types and information identified on the 1:24,000-scale compilation sheets used for both the Surficial Materials Map of Connecticut, Stone and others, 1992 and the Quaternary Geologic Map of Connecticut and Long Island Sound Basin. All attributes have valid values. Values are within defined domains. The accuracy test for the SMPOLY_COD and QUPOLY_COD attribute values was conducted by comparing the geologic map unit information presented on the source mylar overlays with 1:24,000-scale check plots or interactive displays of the digital data on a computer graphic system. These check plot maps and computer displays depicted and labeled the polygon features in different colors and line-fill patterns based on SMPOLY_COD and QUPOLY_COD attribute values for comparison with the original data source. SURFM_POLY and SM_DESC represent both brief and full text English language equivalents of (decodes) the SMPOLY_COD attribute, respectively. The AV_LEGEND and IMS_LEGEND polygon attributes are based on and key off the QUPOLY_COD attribute. These related attributes were populated by joining to lookup data tables using the SMPOLY_COD as the relate key field instead of manually entering these values for each polygon feature. These lookup data tables contain records that account for and describe the unique occurrences of SMPOLY_COD values. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet. For line features, the QSARC_COD attribute that distinguishes contact boundaries from shoreline boundaries was manually entered for each feature.
Polygon features conform to the following topological rules. Polygons are single part. There are no duplicate polygons. Polygons do not self overlap. Polygons do not overlap other polygons. Lines are single part. Line features conform to the following topological rules. There are no duplicate lines. Lines do not self overlap. Lines do not overlap other lines. Lines intersect only at nodes, and nodes anchor the ends of all lines. Lines do not overshoot or undershoot other lines they are supposed to meet and intersect. In general, there are no duplicate features, unresolved intersections, overshooting lines, open polygons, sliver polygons, or unlabeled (unattributed) polygons. The tests of logical consistency were performed by the State of Connecticut using ESRI ArcInfo software to maintain feature topology in ArcInfo coverage format. The data is topologically clean. The ArcInfo Clean function was repeatedly used following edits to verify topology and enforce a minimum distance between vertices of 4 feet (fuzzy tolerance) and a minimum allowed overshoot length of 0 feet (dangle length).
The data reflects the content of the data source, which is a set of 1:24,000 scale mylar sheets used to compile and publish the Surficial Material Map of Connecticut, Stone and others, 1992 (U.S. Geological Survey in cooperation with the Connecticut Geological and Natural History Survey, DEP, 2 sheets, 1:125,000 publication scale), and the Quaternary Geologic Map of Connecticut and Long Island Sound Basin, Stone and others, 2005 (U.S. Geological Survey in cooperation with the Connecticut Geological and Natural History Survey, DEP, 2 sheets, 1:125,000 publication scale). The datalayer was digitized from these 1:24,000-scale mylar compilation sheets. This datalayer (QUPOLY_COD - Quaternary Map unit label abbreviations) was updated to reflect minor editorial comments relating to the 2005 publication of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin. All 116 Connecticut quadrangles of mapped on-land Quaternary and surficial materials units have been digitized and included in this data layer; all off-shore Quaternary units have been digitized as a separate effort and are available as separate data layers (LISQMOR, LISQLAKE, LISQFAN, LISQCHAN, LISQMARD).
The horizontal positional accuracy of this data complies with the United States National Map Accuracy Standards for 1:24,000 scale maps. According to this standard, not more than 10 percent of the locations tested are to be in error by more than 1/50 inch (40 feet) measured on the publication scale of a USGS 7.5 minute topographic quadrangle map. Feature locations were interpolated from the transporation features, surface water features, elevation contours, buildings, built-up areas, and other natural features and landforms depicted on USGS 7.5 minute topographic quadrangle maps. Conforms with Connecticut DEP Spatial Data Standards. Standards for feature accuracy are: 90 percent of the digitized features are within .01 inch of the centerline of that feature on the manuscript (original map); 100 percent of all features must be within .02 inch. There are no duplicate features, unresolved intersections, overshooting arcs, open polygons, sliver polygons, or unlabeled polygons. Fuzzy and Dangle Tolerances were verified and set in the ArcInfo coveage tolerance (TOL) file.
Quaternary map units (contacts and descriptions) and depositional system information.
Surficial Materials units (contacts and descriptions). Includes the 1:24,000-scale mylar overlay compilation sheets used to publish the Surficial Materials Map of Connecticut, Stone and others, 1992. Compilation sheets based on published and unpublished 1:24,000-scale surficial geolgic maps available to the compiler. Depending on the 7.5 minute quadrangle, data sources include Connecticut Geological and Natural History Survey Quadrangle Report (QR), U.S. Geological Survey Geologic Quadrangle Map (GQ), U.S. Geological Survey Miscellaneous Field Studies Map (MF), U.S. Geological Survey Miscellaneous Geologic Investication Map, U.S. Geological Survey Open-File Report, U.S. Geological Survey Open-File Map, University of Connecticut thesis, or unpublished data. For a complete list of data sources by 7.5 minute quadrangle, refer to Sheet 2 of the Surficial Materials Map of Connecticut, Stone and others, 1992. Topographic bases used in the original geologic compilation from USGS 1:24,000 scale revisions 1952-1970.
Surficial Materials is in ArcInfo Coverage format having both polygon and line features. The name of the ArcInfo Coverage is SURFMAT.
ArcInfo coverage
ArcInfo coverage
Includes all polygon features from CTQSGEOM (ArcInfo Coverage format). Quaternary_Geology_Poly.shp is in Shapefile format.
Quaternary_Geology_Poly is in GeoDatabase Feature Class format.
Feature digitizing (digitizing tablet method) - Using ESRI ArcInfo software, features were digitized by registering each source Mylar to the digitizing tablet and using the crosshairs of the digitizer's mouse to manually capture the geometry (location) of features drafted on the map. The corners of the USGS 7.5 minute topographic quadrangle maps are used as registration points and are depicted on the source map. Each source map was registered to the digitizing tablet by digitizing (entering) the locations of four quadrangle corner registration points shown on the map. ArcInfo software compared the values of the digitized coordinates with the actual (true) values for the quadrangle corner (tic) features. The Root Mean Square (RMS) error generated by the ArcInfo software indicated the amount of error involved in transforming coordinates from the registered map to the digital layer. RMS errors higher than 0.004 were not acceptable and required re-registering the source map by digitizing the tic locations again. Surficial material boundary lines (contacts) delineated on each source map were manually digitized according to the following spatial data accuracy standards: Standards for feature accuracy are: 90 percent of the digitized (linear) features are within .01 inch of their centerline on the original manuscript (source map); all digitize (linear) features are within .02 inch of their centerline on the original manuscript. Polygon features were created as a result of digitizing these (boundary) line features. The source maps are made from stable-base mylar. Selected waterbodies greater than 5 acres and related shoreline features were incorporated from existing digital hydrography data. Digital compilation utilized hydrography from 7.5 minute, 1:24,000-scale U.S. Geological Survey Digital Line Graph source material (1969-1984) with minor modification of geologic contacts to fit the revised hydrography where necessary. Hydrography selected from the USGS Digital Line Graph data (code numbers 050 0412,050 0421, and 050 0116) include streams, lakes, ponds, bays, estuaries, and seas with areas greater than 5 acres. In general, units shown on the 1:24,000-scale compilation sheets are typically those published on the 1:125,000-scale Surficial Materials Map of Connecticut. Additional map units may be present in the digital data that could not be readily shown on the published map at 1:125,000 scale or that represent more recent mapping, particularly along the coast. Some subsurface information as noted by stacked units may also be more detailed in the 1:24,000-scale digital data than that of the published 1:125,000-scale State Map. Attribution - Each polygon feature was manually assigned the corresponding SMPOLY_COD attribute, indicating the geologic unit type based on information the compilation sheets. Additionally, line features were manually attributed with SMARC_COD values to distinguish geologic contacts from shoreline and the state boundary. Where necessary, additional minor corrections (edits) to feature geometry were manually digitized on the screen (heads-up digitizing) at display scales greater than 1:24,000. Feature location and attribute accuracy was visually checked and inspected by symbolizing and labeling features according to attribute value on the computer screen and on hard copy paper maps, and comparing this information to the original source data. These check plot maps were printed at the same scale as the source maps in order to visually inspect digitizing quality and the assignment of attribute values. Edgematching - Features along the boundaries of adjacent 7.5-minute quadrangle coverages were made to match (connect) to each other through a process of checkerboard style edgematching. Following a checkerboard pattern, line features were only adjusted on every other quadrangle. The edgmatching process resulted in defining the same point coordinate where line features from two adjacent quadrangles connect along quadrangle boundaries. Essentially, line end points were snapped to connect to line end points of the corresponding stationary linear features on adjacent quadrangles. Edge matching was successfully completed once it was possible to append all 7.5-minute quadrangle coverages and assemble a statewide coverage with polygons that closed without gaps (slivers) and overlaps. Appending - Subsequently, all 7.5-minute quadrangle coverages were appended to form a single, statewide Surficial Materials layer. Polygon features were merged across quadrangle boundaries. Linear features were unsplit (merged) to eliminate unnecessary pseudo nodes that connected similar line features (originally from different quadrangle coverages). Final polygon and line feature topology was established with ArcInfo Fuzzy and Dangle tolerances verified at 4 and 0 feet, respectively. Lookup tables were joined to the polygon and feature attribute to include additional attributes that decoded the SMPOLY_COD and SMARC_COD attributes such as SURFM_POLY, SURFM_ARC, DESC, and IMS_LEGEND. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet. At this step in the process the Surficial Materials layer was fully attributed and ready for use.
UConn Avery Point
1080 Shennecossett Rd
Quaternary units contacts manually digitized from 1:24,000 scale mylar compilation sheets using a Calcomp 9100 digitizing table, using the same standards decribed in Process step 1. These new Quaternary Geologic contacts were added to the existing digital Surficial Materials data layer and attibuted (QSARC_COD = 4). This was done because approximately 90% of the arcs defining the Quaternary Geology are the same as those defining the Surficial Materials polygons; although they were produced as separate USGS publications the maps were developed under a single philosophy and represent multiple attibutes of unified geologic model. All new vectors were edgematched, polygon topology was recreated. QSPOLY_COD was added and manually attributed. Line work and attibutes were checked by the on 1:24,000 scale plots and edited as necessary by the proceedure described in process step 1. Final polygon and line feature topology was established with ArcInfo Fuzzy and Dangle tolerances verified at 4 and 0 feet, respectively
UConn Avery Point
1080 Shennecossett Rd
Quaternary polygon attributes QSPOLY_COD, and QUATGEOL were updated to coincide with minor edits to published (paper) Quaternary Geologic Map of Connecticut and Long Island Sound Basin.
UConn Avery Point
1080 Shennecossett Rd
Export to Shapefile Format - Converted polygon feature data from ArcInfo Coverage named CTQSGEOM version 2.0 to a Shapefile named Quaternary_Geology_Poly.shp. Excluded the AREA, PERIMETER, CTQSGEOM#, CTQSGEOM-ID attributes from the Shapefile because their values are only maintained by ArcInfo software with data that is in ArcInfo Coverage format.
79 Elm Street
Convert to GeoDatabase Feature Class format - Defined new Feature Class named Quaternary_Geology_Poly; and imported the attribute definitions, loaded features and imported metadata from Quaternary_Geology_Poly.shp shapefile. Spatial Reference Properties for Feature Class: Coordinate System: NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet XY Domain MinX: 100000; MaxX: 2247483.645 XY Domain MinY: 200000; MaxY: 2347483.645 Precision: 1000
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Internal feature number.
ESRI
Feature geometry.
ESRI
Quaternary Geology Polygon Code - The key field used to classify Quaternary Geology units. Attribute values are map unit labels, less than 6 characters in length. Unit descriptions are included as attribute value definitions.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Artificial fill-Earth and manmade materials including rocks, gravel, sand, silt, clay, concrete, and select refuse artificially and extensively emplaced, principally in coastal areas. Highway and railroad fill, areas of landfills, and local fill in urban areas are not mapped.
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Flood-plain alluvium - Sand, gravel, silt, minor clay, and some organic material in flood plains of modern streams. Along smaller streams, texture of alluvium is commonly variable both laterally and vertically, but overall texture is often similar to adjacent glacial materials. Thickness commonly less than 2 m (6 ft). Along larger rivers, contains gravel and sand at base, overlain by laminated sand, silt, and minor clay, as much as 8 m (25 ft) thick. Alluvium of Connecticut River north of Rocky Hill is chiefly very fine sand and silt, less than 5 m (18 ft) thick. Along Connecticut River south of Rocky Hill, alluvium is chiefly fine to medium sand, as much as 12 m (40 ft) thick. Alluvium overlies glacial stratified sand and gravel, coarse gravel, or till in upland valleys; in lowlands, commonly overlies sand or silty-clayey lake-bottom deposits
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Swamp deposits-Muck and peat that contain minor amounts of sand, silt, and clay overlying laminated organic silt, clay, and sand. Organic peat and muck is decomposed, fibrous and granular, woody herbaceous material. Thickness of organic materials is commonly less than 3 m (10 ft). Some deposits accumulated in poorly drained areas, mostly in shallow, low-lying basins in till and (or) bedrock areas; other deposits accumulated in relatively deep, closed depressions (kettles) in ice-proximal, glacial meltwater deposits, and in shallower depressions and swales on glacial lake-bottom surfaces; some deposits occupy low swales between alluvial levees on Holocene flood-plain surfaces. Thicker peat and muck deposits (for example, 4 m (13 ft) at Totoket bog, a kettle-hole swamp just north of Route 80 and west of Bare Plain cemetery in the village of Totoket in the Branford quadrangle; 10 to 14 m (33 to 46 ft) beneath Linsley Pond and Cedar Pond in North Branford; 11 m (36 ft) beneath Rogers Lake in Lyme; and 4 m (13 ft) at Durham Meadows) preserve a record of vegetation changes and hence a paleoclimatic record for postglacial time. Oldest postglacial radiocarbon dates in Connecticut (~15 ka) come from base of organic swamp deposits at Totoket bog and Rogers Lake. Generally overlie materials of adjacent map unit. Shown only where greater than 25 acres in area
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Tidal-marsh deposits - Peat and muck, generally 1 to 9 m (3 to 30 ft) thick, interbedded at depth with laminated fine sand and silt. Organic peat and muck is decomposed, fibrous and matted, herbaceous and silty-herbaceous material that accumulated in marshes at and upstream from mouths of streams open to marine waters of Long Island Sound; marshes include coastal salt marshes and brackish to freshwater tidal marshes farther up estuaries. Vegetation growing today in tidal marshes as well as plants preserved in peat deposits ranges from salt-water species (such as Spartina alterniflora and S. patens) to species tolerant to brackish water (such as Typha angustiflora and Phragmites australis) to freshwater sedge and rush species (such as Scirpus fluviatilus, Juncas accumintus, and Pontederia cordata). Vertical accretion and upstream (northward) transgression through time records drowning of former alluvial terraces along coastal streams during postglacial sea-level rise. Basal portion of most of the tidal-marsh deposits shown on map lies on surfaces above -5 m (-15 ft) mean sea level (MSL); a sea-level-rise curve generated from radiocarbon dates from tidal-marsh peat deposits along lower Connecticut River (Patton and Horne, 1991) indicates marine transgression beginning 4,000 years ago. In some places, such as marsh along Hammock River in Clinton, salt-marsh peat overlies estuarine deposits; these peat deposits are composed of organic sand and silt and freshwater sedge peat at depths of up to -12 m (-40 ft) MSL, which yield older radiocarbon dates that indicate a marine transgression beginning 7,000 years ago (Bloom and Stuiver, 1963; van de Plassche and others, 1989). Shown only where greater than 25 acres in area
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Talus - Angular, loose blocks of basalt and diabase accumulated by rockfall and creep at base of bedrock cliffs along linear traprock ridges in Central Lowland. Forms steep unstable slopes. Generally less than 6 m (20 ft) thick
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Coastal beach and dune deposits - Fine to coarse sand and local pebble-cobble gravel in modern beach deposits. Texture of beach deposits varies over short distances and is generally controlled by texture of nearby glacial materials exposed to wave action. Beach deposits are poorly to well sorted and enerally less than 2 m (6 ft) thick. Locally includes dune deposits consisting of relatively well sorted, fine to coarse sand in transverse coastal eolian dunes that are 1 to 3 m (3 to 10 ft) thick
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Stream-terrace deposits - Sand, gravel, and silt deposited by meteoric water on terraces that were cut into glacial meltwater sediments. Texture is variable vertically and laterally, but is chiefly coarse pebbly sand, commonly similar to that of adjacent glacial deposits. Thickness ranges from 1 to 5 m (3 to 15 ft). Distinguished from meltwater-terrace deposition by its lower position in valley, commonly only 3 to 6 m (10 to 20 ft) above altitude of modern flood plains
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Medium, relatively well sorted sand, in transverse, parabolic, and hummocky dunes as much as 12 m (40 ft) thick. Most common in drained basin of glacial Lake Hitchcock where sand was derived from extensive glacial-lake deltaic deposits. Dunes overlying lake-bottom deposits of glacial Lake Middletown and early phase of glacial Lake Hitchcock indicate predominant north-northeast wind direction in early postglacial time. Dunes overlying lake-bottom deposits and stream-terrace deposits in glacial Lake Hitchcock basin indicate predominant north-northwest wind direction after lake drainage; major dune fields cover lake-bottom surface on east side of valley. Dune sand now fixed by vegetation except where disturbed by human activities. Eolian silty sand, generally less than 1 m (3 ft) thick, is widespread in valleys and lower till slopes, but is not shown on map
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Uncorrelated Meltwater Deposits - Sand, gravel, silt, and clay deposited in unidentified systems. Most appear to be ice-contact deposits entirely on glacial ice and collapsed down to present positions in landscape. Locally includes lake-bottom deposits (ruled pattern) that cannot be associated with any particular glacial lake
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Glacial Lake Norfolk deposits - Ice-marginal deltaic deposits and lake-bottom deposits in north-west-sloping Blackberry River valley. Deltas record lake levels in two stages. Deltaic deposits at Norfolk with surface altitude of 410 m (1,345 ft) were controlled by a spillway at 404 m (1,325 ft) across Housatonic and Naugatuck Rivers drainage divide. Ice-marginal deltaic deposits at East Canaan with surface altitudes at 270 m (885 ft) and topset-foreset contacts at about 265 m (870 ft) were controlled by 261-m (855-ft) spillway to northwest around northern end of Canaan Mountain. (Ashley Falls, South Sandisfield, Norfolk)
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Glacial Lake Cornwall deposits - Deposits in southern part of unit indicate either highly collapsed ice-marginal deltas or (more likely) ice-marginal lacustrine fans that did not build up to lake level. Surface altitudes are well below 337-m (1,105-ft) col across southern divide of Valley Brook. Northern deposits include small ice-marginal deltas built into lake from Baldwin Brook and Bloody Brook valleys at three levels: 261 m (855 ft), 230 m (755 ft), and 215 m (705 ft); highest level probably was controlled by 258-m (845-ft) spillway high on southern side of Furnace Brook valley, while ice margin blocked drainage. Lower two levels must have been controlled by ice or till blockage in Furnace Brook valley. Thick lake-bottom deposits occur beneath and in front of 215-m (705-ft) deltaic deposits in Cornwall village. (Cornwall)
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Glacial Lake Hollenbeck deposits - Ice-marginal deltaic and lacustrine fan deposits and lake-bottom deposits in northwest-sloping Hollenbeck River valley. Successive ice-marginal deltas with narrow, ridge-like forms at southern end of lake are at 300 to 303 m (985 to 995 ft) and were controlled by 297-m (975-ft) spillway across divide at southern end of valley. To the north, successive ice-marginal lacustrine fan deposits are at lower than lake-level altitudes; in several exposures, internal bedding of these sediments displays severe, active ice deformation. Later lake stages were controlled by spillways at 215 m (705 ft) and 203 m (665 ft) west of Cobble Mountain. (South Canaan, Cornwall)
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Glacial Lake Danbury, Pumpkin Hill stage deposits - Glacial Lake Danbury was dammed by northerly retreating ice margin in north-sloping Still River valley. Lake had three stages controlled in level by three successively lower spillways. Pumpkin Hill stage deposits - One ice-marginal delta at 114 m (375 ft), controlled by short-lived 114-m (375-ft) spillway across northern end of Pumpkin Hill, adjacent to junction of Still River valley with Housatonic River valley. More extensive ice-marginal deltaic deposits at 90 to 93 m (295 to 305 ft) were graded to last stage of glacial Lake Danbury and controlled by 90-m (295-ft) spillway about 305 m (1,000 ft) farther north on Pumpkin Hill. Narrow bedrock gorge of Housatonic River just downstream from spillway must have been temporarily blocked to permit use of Pumpkin Hill spillway during ice retreat for about 3 km (2 mi) north of gorge. (New Milford)
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Glacial Lake Danbury, Pond Brook stage deposits - Glacial Lake Danbury was dammed by northerly retreating ice margin in north-sloping Still River valley. Lake had three stages controlled in level by three successively lower spillways. Pond Brook stage deposits - Ice-marginal and near-ice-marginal deltaic deposits, esker-fed lacustrine fan deposits, and associated lake-bottom sediments. Near-ice-marginal deltas south of Lake Candlewood have surface altitudes of 126 to 130 m (415 to 425 ft); inset against these is a delta at 114 to 117 m (375 to 385 ft) that was fed by distal meltwater from Lake Candlewood valley. Ice-marginal delta deposits just west of spillway are at 120 to 123 m (395 to 405 ft); other ice-marginal deposits are lacustrine fans that did not build up to lake level. This stage of glacial Lake Danbury was controlled by spillspillway eastward into Pond Brook valley that began initially at about 126 m (415 ft) and was incised down to about 114 m (375 ft) during time of its use. (Danbury, New Milford)
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Glacial Lake Danbury, Saugatuck divide stage deposits - Glacial Lake Danbury was dammed by northerly retreating ice margin in north-sloping Still River valley. Lake had three stages controlled in level by three successively lower spillways. Saugatuck divide stage deposits - Ice-marginal deltas, fluviodeltaic deposits, and associated lake-bottom sediments. Delta surfaces have altitudes of 136 to 139 m (445 to 455 ft); fluvial feeders reach 154 m (505 ft). This stage of glacial Lake Danbury was controlled in level by 127-m (415ft) spillway south into Saugatuck River valley. (Danbury, Bethel)
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Glacial Lake Pootatuck deposits - Successive ice-marginal deltaic deposits in north-draining Pootatuck River valley; near-ice-marginal fluviodeltaic deposits in upper valley. Deltas at 133 to 139 m (435 to 455 ft) in southern part of unit were graded to 130-m (425-ft) and 133-m (435ft) spillways across southern divide. Ice-mar-ginal deltas in Berkshire village at 117 to 120 m (385 to 395 ft) were graded to 114-m (375-ft) spillway to the east; northernmost ice-marginal deltas at 102 to 105 m (335 to 345 ft) were controlled by spillway across Berkshire deltas northward into Pole Bridge Brook valley; floor of this spillway is now at 96 m (315 ft) but was initially 3 to 6 m (10 to 20 ft) higher. (Newtown, Botsford)
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Glacial Lake Winsted deposits - Ice-marginal deltas and fluviodeltaic deposits. Deltas have surface altitudes at 224 to 230 m (735 to 755 ft); extensive fluvial deposits in main valley reach 239 m (785 ft) and in tributary valleys are as high as 274 m (900 ft). Lake was ponded in north-draining Still River valley and controlled in level by three spillways. First was at 224 m (735 ft) and spilled into Naugatuck River valley. Next two successive spillways near Winsted drained into Farmington River valley. These spillways now are at 227 m (745 ft), but were 6 to 9 m (20 to 30 ft) lower relative to the first one before postglacial tilting. (Winsted, Torrington)
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Glacial Lake Nepaug deposits - Ice-marginal deltas in lower (eastern) part of Nepaug River valley and near-ice-marginal deltaic deposits in upper valley. Both sets of deltas record two lake levels. Deltas with surfaces at 215 to 224 m (705 to 735 ft) were graded to lake levels controlled first by 218-m (715-ft) and then 212-m (695-ft) spillway on till-blanketed hillside south of Nepaug Reservoir. Deltas with surfaces at 200 to 203 m (655 to 665 ft) are inset into higher level deltas in upper valley and easterly against higher deltas in lower valley; they were controlled by 191-m (625-ft) spillway downslope from first spillways. Glacial Lake Nepaug was contained in inter-lobate angle between Connecticut Valley ice lobe and western upland ice margin; valley ice-dammed lake and ice-marginal deltas in lower Nepaug River valley were built against it; upland ice margin provided meltwater and sediment to build deltaic deposits in upper valley. Lake lowered as valley ice retreated eastward off hillside south of present Nepaug Reservoir. (Collinsville, Torrington)
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Glacial Lake Bristol deposits - Ice-marginal deltaic and fluviodeltaic deposits in upper Pequabuck River valley and its northern tributaries. Deltas with surfaces at 197 to 200 m (645 to 655 ft) near Terryville controlled by 194-m (635-ft) spillway across Naugatuck River-Farmington River-Quinnipiac River divide. Fluvial feeder deposits as high as 248 m (815 ft) in upper Poland River valley built from upland ice-mar-gin positions and graded to deltas at Terryville. Ice-marginal deltaic deposits in northeastern part of unit were built from ice positions to the northwest and were probably controlled by separate local spillway at 209 m (685 ft). Glacial Lake Bristol was contained in an interlobate angle between Connecticut Valley ice lobe and western upland ice margin. Pequabuck River valley was dammed to very high levels against drainage divide by thick valley lobe ice; ice-marginal deltas were built into lake from lobe ice position; at same time, fluviodeltaic deposits were built into lake from ice to northwest. (Bristol, Thomaston, Collinsville)
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Glacial Lake Coginchaug, Middletown stage deposits - Deposits in lower Coginchaug River and Sumner Brook valleys consist of small ice-marginal deltas, mostly collapsed; narrow noncollapsed fringes of these deltas occur at 81 m (265 ft), 69 m (225 ft), and 56 to 59 m (185 to 195 ft) built into successively lower levels of this stage, controlled by three spillways across rock ridge west of Sumner Brook at 75 m (245 ft), 59 m (195 ft), and 53 m (175 ft). Valley of Sumner Brook also was ponded, spilling out via two successive spillways east of valley at 59 m (195 ft) and 53 m (175 ft). Only a few small deposits at this level exist in Sumner Brook valley. Lake-bottom deposits in Sumner Brook may have accumulated, in part, in glacial Lake Middletown, which succeeded glacial Lake Coginchaug in this valley at lower level. (Middletown, Durham)
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Glacial Lake Coginchaug, Durham stage deposits - In upper Coginchaug River valley, ice-marginal deltas, and ice-marginal and near-ice-marginal fluviodeltaic deposits built by meltwater from tributary valleys. Delta surfaces are at 87 m (285 ft) at southern end of basin and 93 m (305 ft) at northern end. All deposits except very earliest were graded to 84-m (275 ft) spillway across southern Coginchaug River drainage divide. Lake-bottom sediments occur in three areas; largest body, beneath Durham Meadows, may have accumulated mostly during Middletown stage. (Durham, Middletown)
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Glacial Lake Manchester deposits - Predominantly ice-marginal deltaic deposits graded to long, narrow lake between Connecticut Valley ice lobe and upland till slope in south-central Manchester. Two stages of lake were controlled by spillways between bedrock hills; earlier stage with delta surfaces at 84 to 99 m (275 to 325 ft) was controlled by 81-m (265-ft) spillway; later stage delta surfaces are at 66 to 78 m (215 to 255 ft) controlled by 66-m (215-ft) spillway. (Manchester, Rockville)
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Glacial Lake Salmon Brook deposits - Ice-marginal deltaic and fluviodeltaic deposits graded to two stages of long narrow lake initially in Salmon Brook valley, southwestern end of which was dammed by Connecticut Valley ice lobe, and then to the north in southeastern part of city of Manchester. In Salmon Brook valley, fluvial surfaces as high as 96 m (315 ft) grade southwestward to deltas at 81 m (265 ft) controlled by 75-m (245-ft) spillway between two drumlin hills. Ice-marginal deltaic deposits in Manchester have surfaces at 99 m (325 ft) and were controlled by two spillways: one over older 96-m (315-ft) surface has present altitude of 87 m (285 ft), and the other at 87 m (285 ft) between bedrock hills north of Salmon Brook valley. (Glastonbury, Manchester)
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Glacial Lake Roaring Brook deposits - Ice-marginal deltaic and fluviodeltaic deposits graded to three stages of long, narrow lake in Roaring Brook Valley, southwestern end of which was blocked by Connecticut Valley ice lobe. Ice-marginal deltaic deposits with 136- to 139-m (445- to 455-ft) surfaces on southeastern side of Roaring Brook valley, graded to 126-m (415-ft) spillway. Fluvial deposits that head west of Minnechaug Mountain, north of valley, are at 130 m (425 ft) and grade southwestward into valley to deltas with surfaces at 111 to 114 m (365 to 375 ft), controlled by 105-m (345-ft) spillway. Predominantly deltaic deposits with surfaces at 108 to 114 m (355 to 375 ft) west of Minnechaug Mountain were graded to 105-m (345-ft) spillway across older deposits; meltwater from this spillway entrenched and terraced older 111- to 123-m (365- to 405-ft) surfaces and constructed deltas at southern end of unit with surfaces at 87 to 93 m (285 to 305 ft), controlled by 87-m (285-ft) spillway. (Glastonbury, Rockville)
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Glacial Lake Colchester deposits - Successive ice-marginal deltas with surface altitudes of 114 to 120 m (375 to 395 ft) deposited in earlier stage of lake in Nelkin Brook and Meadow Brook valleys. Spillway across Colchester deposits (lc) began at about 117 ft (385 ft) and eroded down to bedrock at 111 m (365 ft). Ice-marginal deltas built into later stage of lake in Judd Brook and Raymond Brook valleys have surfaces at 120 to 130 m (395 to 425 ft); controlled by spillway at 114 m (375 ft). Meltwater flow across spillway eroded last delta of older stage of lake, because older stage drained while younger stage still existed. (Colchester)
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Glacial Lake Essex deposits - Four small ice-marginal deltas graded to four early-stage spillways across southern Falls River drainage divide; ice-marginal fluviodeltaic deposits in Falls River valley and northern tributaries. Fluvial feeder deposits reach 35 m (115 ft) and grade to deltaic surfaces in Centerbrook at 11 to 14 m (35 to 45 ft); controlled by spillway at southern part of Essex village at 11 m (35 ft). Early ice-marginal deltas probably built at nearly same time, while ice still occupied Falls River valley. When Falls River valley was uncovered, ice margin continued to block mouth of valley north of Essex village, creating main part of lake basin. (Essex, Deep River)
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Glacial Lake Oneco deposits - Successive ice-marginal deltaic deposits in Moosup River valley and ice-marginal and near-ice-marginal fluviodeltaic deposits in northern tributary valleys, some of which are in Rhode Island. A free-front delta at Oneco with lake-bottom sediments in front of it was built westward into lake fed by ice-marginal fluvial deposits farther upstream in Moosup River valley in Rhode Island. Ice-marginal fluvial deposits in Quanduck Brook valley are at 169 m (555 ft) and grade southward on steep gradient to 123- to 126-m (405- to 415ft) deltas built into lake. Lake was dammed by ice margin in west-northwest-draining Moosup River valley and was controlled by three spillways. Highest spillway at 114 m (375 ft) is just over border in Rhode Island as are the deltas it controlled; a lower spillway that controlled most deposits in Connecticut crosses Quinebaug River-Pawcatuck River divide at 111 m (365 ft). A 108-m (355-ft) notch cut into a thick till hillside at last ice-margin position may have controlled level of lake for a short period of time before further ice retreat caused lake to empty. (Oneco)
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Glacial Lake Voluntown deposits - Successive ice-marginal deltas related to at least seven ice-margin positions. Several esker-fed lacustrine fan deposits that did not quite build up to lake level occur in central part of lake basin. Lake-bottom deposits exist at surface in few small areas that remained as open water. Lake existed in three stages, controlled by successive spillways at 123 m (405 ft), 111 m (365 ft), and 102 m (335 ft) across Quinebaug River-Pawcatuck River divide. (Voluntown)
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Glacial Lake Pachaug deposits - Predominantly successive ice-marginal deltas in Pachaug River basin including some esker-fed deltas. Lake-bottom sediments underlie meltwater-terrace deposits in central part of basin and probably occur beneath Pachaug Pond as well. Ice-marginal fluviodeltaic deposits occur as one morphosequence in northeastern part of unit. Deposits are related to at least 10 ice-margin positions. Glacial Lake Pachaug existed in three successively lower stages controlled by spillways across divide on western side of basin. Earliest delta was built into highest stage controlled by 72-m (235-ft) spillway when ice margin was at southern end of basin. Several succeeding deltas were deposited in second stage of lake controlled by 69-m (225-ft) spillway. Last and longest-lived stage of lake controlled by 59-m (195-ft) spillway is recorded by deltas built at six successively northward ice-margin positions. Further ice retreat caused glacial Lake Pachaug to drain westward into Quinebaug valley and caused water levels to lower to altitude of glacial Lake Quinebaug. (Jewett City)
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Glacial Lake Great Falls deposits - Ice-marginal deltaic deposits and extensive lake-bottom sediments in Housatonic River valley from Great Falls northward into Massachusetts. Ice-marginal deltas are at 206 to 209 m (675 to 685 ft) near Canaan village. Lake-bottom deposits are as much as 30 to 61 m (100 to 200 ft) thick in overdeepened bedrock basin in easily erodible marble. Spillway was lip of modern Great Falls, initially perhaps 3 to 5 m (10 to 15 ft) higher than present 192-m (630-ft) level. Lake extended northward into Massachusetts. (Ashley Falls, South Canaan)
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Glacial Lake Lime Rock deposits - Ice-marginal deltas with surfaces at 181 to 187 m (595 to 615 ft) and lake-bottom sediments built into small lake at junction of Salmon Creek valley with Housatonic River valley. Lake was dammed behind ice-contact head of Housatonic River deposits (hrn); spillway across Housatonic River was removed by postglacial incision of river. (South Canaan, Sharon)
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Glacial Lake Kenosia deposits - Extensive lake-bottom deposits at lower end; delta rises west to ice-contact head just across State line in New York. Water from this lake eroded thick till along Still River and spilled into glacial Lake Danbury. (Brewster, Danbury)
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Glacial Lake Bantam deposits - Ice-marginal and near-ice-marginal deltas with surfaces at 276 to 282 m (905 to 925 ft). Initial spillway at 276 m (905 ft) across divide at southern end of present Bantam Lake; later control of glacial lake level was across till surface at present lake outlet. Basin in which glacial lake existed and in which modern lake remains formed by deposition of extensive thick till in Litchfield drumlin field. (Litchfield)
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Glacial Lake Pomperaug deposits - Ice-marginal deltaic and fluviodeltaic deposits, near-ice-marginal fluviodeltaic deposits, and associated lake-bottom sediments. Successive ice-marginal deltaic and fluviodeltaic deposits in southern part of unit have surface altitudes of 78 to 81 m (255 to 265 ft). Initial ponding was behind Housatonic River deposits (hrs); spillway across those deposits was incised from about 72 m (235 ft) to 66 m (215 ft). Northern part of unit consists largely of fluviodeltaic deposits; long fluvial feeder deposits reach 154 m (505 ft) in Weekeepeemee River valley and 123 m (405 ft) in Nonewaug River and Sprain Brook valleys and grade to deltaic deposits at Woodbury with surface altitudes of 87 to 96 m (285 to 315 ft). This later lake drainage spilled across earlier deposits at Pomperaug village and may have finally stabilized in bedrock spillway at 78 m (255 ft). (Woodbury, Southbury)
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Glacial Lake Tariffville deposits - Deltaic deposits overlying lake-bottom sediments more than 30 m (100 ft) thick in lower Salmon Brook valley. Ice-marginal fluvial deposits at Goodrichville reach 84 m (275 ft) and are on grade with deltaic surfaces to the south at 75 m (245 ft). West of Manitook Mountain, highly collapsed ice-marginal deposits grade to delta surfaces as high as 84 m (275 ft) that contain as much as 9 m (30 ft) of topset beds. Level of glacial Lake Tariffville was controlled at Farmington River gap through Talcott Mountain and was most likely water plane of glacial Lakes Middletown and Hitchcock to the east. Some slightly lower surfaces at 59 to 66 m (195 to 215 ft) are terraces or inset deltas graded to lowering water levels in glacial Lake Hitchcock. (Tariffville)
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Glacial Lake Farmington deposits - Ice-marginal fluviodeltaic deposits in Roaring Brook valley near Unionville and west of Farmington River in Avon. Fluvial surfaces reach 93 m (305 ft) and are on grade southward to deltaic surfaces at 81 to 84 m (265 to 275 ft) at Unionville and 78 to 81 m (255 to 265 ft) in Farmington. Deposits east of Farmington River in Avon are successive ice-marginal deltas with several feeder eskers; deltaic surfaces are at 84 to 87 m (275 to 285 ft). South of Farmington River, fluviodeltaic deposits were built against tongue of ice in valley; deltaic surfaces are at 72 m (235 ft), and fronts of these deltas were erosionally trimmed by later meltwater that deposited Quinnipiac River valley terrace deposits (qt) in central portions of valley. Distal lacustrine sand containing climbing ripples that indicate northward current directions can be seen in several places beneath unit qt; this material was supplied to lake by meltwater from Pequabuck River valley carrying sediment derived from crystalline rock. Spillway for this lake was initially across till deposits incised from about 67 m (220 ft) to 58 m (190 ft); subsequent melting of buried ice in Quinnipiac River valley and lowering of glacial Lake Southington caused outlet to switch positions so that spillway was across deposits of glacial Lake Southington (ls). (New Britain, Bristol, Avon, Collinsville)
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Glacial Lake Southington deposits - Successive ice-marginal esker-fed deltas in Quinnipiac River valley, each of which has a collapsed proximal head on northern side and free-front delta slopes on southern side. Lake-bottom sediments occur in front of each delta. In western tributary valley, single ice-marginal fluviodeltaic deposit occurs with lake-bottom sediments at southern end. Delta topset-foreset contacts in towns of Cheshire and Southington occur at 59 to 60 m (193 to 196 ft), and indicate spillway at about 56 m (185 ft) over blocking material near present Quinnipiac Gorge. Quinnipiac River-Mill River deposits (qm) occur at 58 m (190 ft) on both sides of Quinnipiac River immediately west of gorge and provided some blockage to dam the lake. Gorge probably was blocked with thick deposits of till; however, it is possible that bedrock gorge did not yet exist and was carved by water spilling from glacial Lake Southington and succeeding lakes to the north. (Southington, Meriden, Bristol, New Britain)
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Glacial Lake Quinnipiac deposits - Consists of an extensive delta in North Haven and small area of lake-bottom sediments exposed by clay pit operations. Entire lower Quinnipiac River valley from north of Fair Haven to South Meriden contains lacustrine deposits of glacial Lake Quinnipiac in subsurface, beneath extensive Quinnipiac River valley fluvial terrace deposits (qt); lacustrine deposits consist principally of varved silt and clay (New Haven clay of Flint, 1933) as much as 49 m (160 ft) thick. Delta at North Haven has ice-margin position on its north side, but foreset dip directions indicate that it was built mainly from meltwater coming from the northeast down Muddy River valley. Topset-foreset contacts (Lougee, 1938) in this delta indicate a 9- to 11-m (30- to 35-ft) altitude water plane at Fair Haven where glacial Lake Quinnipiac spilled across lobe of New Haven delta plain (lcnh), which had built out across former Quinnipiac River channel and blocked valley. New Haven delta acted as sediment dam to impound glacial Lake Quinnipiac above level of glacial Lake Connecticut during construction of Muddy River delta. Water spilling from glacial Lake Quinnipiac probably fairly quickly incised dam to level of glacial Lake Connecticut to the south; however, no exposed deltas exist to the north of Muddy River delta to record lower lake levels. (Branford, New Haven, Wallingford)
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Glacial Lake Hitchcock, Beach deposits - Terrace-like deposits of sand on eastern shore of glacial Lake Hitchcock, ranging from 35 m (115 ft) in the south to 44 m (145 ft) in the north. These altitudes project to stable 25-m (82-ft) level of lake; some areas of beach deposits show slightly higher levels up-slope to the east. (Broad Brook, Manchester)
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Glacial Lake Hitchcock, Lake-bottom deposits - Varved silts and clays in couplets ranging from 1 to 4 cm (0.4 to 1.6 in) thick and probably representing annual deposition. Well logs indicate that silt-clay couplets are thicker and red in color in lower part of section; these are overlain by alternating red and gray sediments; silt-clay couplets are thinnest in upper part of section and are gray. Numerous surface exposures indicate that top 2 to 3 m (6 to 10 ft) of section consists of thinly bedded silt and fine sand of sandy lake-bottom facies. Deposits are areally extensive and commonly greater than 15 m (50 ft) thick, as much as 80 m (260 ft) thick in some places
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Glacial Lake Hitchcock, high-level, Windsor deltaic deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Windsor deltaic deposits - Ice-marginal deltaic deposits in northeastern part of unit with surfaces at 59 to 61 m (195 to 200 ft); topset-foreset contact at 54 m (178 ft) (projects to NBS at 35 m (114 ft)). Deltaic deposits in southwestern part of unit with surfaces at 50 to 56 m (165 to 185 ft) were fed by distal meltwater; sediment was supplied to lake by early Farmington River-Salmon Brook meltwater drainage eastward through Tariffville Gap. (Windsor Locks, Hartford North)
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Glacial Lake Hitchcock, high-level, East Windsor fluviodeltaic deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). East Windsor fluviodeltaic deposits - Highly collapsed fluvial deposits with remnant surfaces as high as 69 to 72 m (225 to 235 ft) in northern part of unit grade southward along ice-margin position to deltaic deposits at 53 to 56 m (175 to 185 ft) in southern part of unit. (Broad Brook)
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Glacial Lake Hitchcock, High-level Hockanum River delta deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). High-level Hockanum River delta deposits - Small delta with surface at 38 to 41 m (125 to 135 ft) and topset-foreset contact about 35 m (115 ft) (projects to NBS at 32 m (104 ft)); built by meteoric water in Hockanum River and Hop Brook valleys. (Manchester)
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Glacial Lake Hitchcock, High-level Scantic River delta deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). High-level Scantic River delta deposits - Ice-marginal delta with surface at 59 to 62 m (195 to 205 ft) in southern part of unit. Distal-meltwater-fed delta with surfaces at 56 to 59 m (185 to 195 ft) in northern part of unit. (Broad Brook)
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Glacial Lake Hitchcock, high-level, Rattlesnake Brook deltaic deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Rattlesnake Brook deltaic deposits - Ice-marginal deltas with surfaces at 59 to 62 m (195 to 205 ft). (West Springfield, Windsor Locks)
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Glacial Lake Hitchcock, high-level, Shea Corner deltaic deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Shea Corner deltaic deposits - Ice-marginal deltaic deposits that extend into Massachusetts. Surfaces at 59 to 62 m (195 to 205 ft). (West Springfield)
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Glacial Lake Hitchcock, high-level, Enfield deltaic deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Enfield deltaic deposits - Deltaic deposits with surfaces at 59 to 62 m (195 to 205 ft) are distal parts of fluviodeltaic deposits built from ice-margin position north of map area in Massachusetts. Estimated lake level of 58 m (190 ft) (projects to NBS at 30 m (99 ft)). (Springfield South)
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Glacial Lake Hitchcock, high-level, Ice-hole deposits - Ice-marginal deltas and fluviodeltas, distal-meltwa-terfed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Ice-hole deposits - Collapsed, ice-contact sand and gravel deposits that encircle hills (mostly drumlins) which were islands in glacial Lake Hitchcock. As ice margin in lake thinned and melted away from island hillsides, deposits probably fed by subglacial meltwater streams accumulated in ice-walled depressions around drumlin hillsides. Glacial Lake Hitchcock water levels apparently controlled altitude of these deposits, because none were built to higher levels. (West Springfield, Hartford North, Manchester)
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Glacial Lake Hitchcock, high-level, Spit deposits - Ice-marginal deltas and fluviodeltas, distal-meltwater-fed deltas, and a meteoric-water-fed delta. Delta altitudes adjusted for glacio-isostatic tilting and projected to New Britain spillway (NBS) record early lake levels from 35 m (115 ft) to about 29 m (95 ft). Spit deposits - Northeast-trending spits composed of southwest-dipping sandy foreset beds on southwestern ends of drumlin islands; generally smaller in size on drumlins lacking ice-hole deposit collar and larger in size on those that have it. Spits were built by waves and currents generated by early paleowinds from the northeast when ice margin was still nearby. (West Springfield, Windsor Locks, Broad Brook, Hartford North, Manchester)
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Glacial Lake Hitchcock, stable-level, Bradley International Airport delta deposits - Meteoric-water-fed deltas and extensive lake-bottom deposits. Delta altitudes, when adjusted for glacio-isostatic tilting and projected to NBS, record 25-m (82-ft) stable lake level that began when ice margin was in southern Massachusetts. Bradley International Airport delta deposits - Large delta built by meteoric water from Farmington River valley that flowed through Tariffville Gap and discharged northeastward into glacial Lake Hitchcock. Delta probably is complex; in places in subsurface, older foreset beds built by distal meltwater from Farmington River valley into higher lake levels may lie beneath present delta surface. Delta surface slopes from 56 m (185 ft) in southwest to 47 m (155 ft) in the north and east. Topset-foreset contact at 47 m (154 ft) (projects to NBS at 25 m (82 ft)). (Windsor Locks)
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Glacial Lake Hitchcock, Stable-level Scantic River and Broad Brook delta deposits - Meteoric-water-fed deltas and extensive lake-bottom deposits. Delta altitudes, when adjusted for glacio-isostatic tilting and projected to NBS, record 25-m (82-ft) stable lake level that began when ice margin was in southern Massachusetts. Stable-level Scantic River and Broad Brook delta deposits - Small deltas with surfaces at 47 to 50 m (155 to 165 ft) built by meteoric water in Scantic River and Broad Brook valleys as it entrenched high-level deposits and entered lower lake level. (Broad Brook)
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Glacial Lake Hitchcock, Stable-level Hockanum River delta deposits - Meteoric-water-fed deltas and extensive lake-bottom deposits. Delta altitudes, when adjusted for glacio-isostatic tilting and projected to NBS, record 25-m (82-ft) stable lake level that began when ice margin was in southern Massachusetts. Stable-level Hockanum River delta deposits - Small delta with surface at 32 to 35 m (105 to 115 ft) built by meteoric water in Hockanum River and Hop Brook valleys as it entrenched deposits of the high-level Hockanum River delta deposits (lhhh) and entered lower level lake. (Manchester)
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Glacial Lake Hitchcock post-stable-level Farmington River delta deposits - Meteoric-water-fed delta with surface altitude of 41 m (135 ft) and topset-foreset contact at 39 m (127 ft); this altitude projects to NBS at 21 m (70 ft), which is 4 m (12 ft) lower than stable level. This delta represents relatively short period of time during which level of glacial Lake Hitchcock was lowered, probably due to first effects of postglacial uplift and before lake drained due to failure of dam. Farmington River terrace deposits (ft) are fluvial deposits associated with this delta; these terraces are inset into stable-level delta surface of Bradley International Airport delta deposits (lhsb). (Windsor Locks, Hartford North)
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Glacial Lake Middletown, Great Pond delta deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Great Pond delta deposits - Ice-marginal delta with surface altitude of 59 to 62 m (195 to 205 ft); topset-foreset contact at about 55 m (182 ft) (projects to spillway at 21 m (68 ft)). (Windsor Locks)
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Glacial Lake Middletown, Windsorville deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Windsorville deltaic deposits - Ice-marginal deltaic deposits at 59 to 62 m (195 to 205 ft) built at the same time as Great Pond delta deposits (lmg) on western side of ice lobe; ice-proximal side of these deposits subjected to slight readvance of ice margin, which pushed deltaic material up into a small moraine (m). (Broad Brook)
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Glacial Lake Middletown, Western margin deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Western margin deltaic deposits - Ice-marginal deltas in New Britain and West Hartford with surface altitudes of 50 to 53 m (165 to 175 ft). Fluviodeltaic deposit at southern edge of New Britain has deltaic surface at 50 m (165 ft) and was built by meltwater flowing eastward through Cooks Gap. (Avon, New Britain)
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Glacial Lake Middletown, Eastern margin deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Eastern margin deltaic deposits - Ice-marginal fluviodeltaic deposits; fluvial deposits as high as 78 m (255 ft) just west of Rockville in Hockanum River valley grade southwestward to deltaic surfaces near Manchester at 53 to 56 m (175 to 185 ft). Distal deltaic sands and lake-bottom sediments are highly collapsed south of Manchester. (Ellington, Rockville, Manchester, Glastonbury)
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Glacial Lake Middletown, Hockanum River delta deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Hockanum River delta deposits - Meltwater-fed delta with surface altitude of 47 m (155 ft) and topset-foreset contact at 42 m (138 ft) (projects to spillway at 20 m (65 ft)). Constructed by meltwater spilling from glacial Lake Ellington, entrenching and reworking deposits of eastern margin deltaic deposits (lme) as meltwater entered glacial Lake Middletown at southern end of Hockanum River valley. Inset fluvial terrace deposits (ht) in Hockanum River valley are on grade to delta. (Manchester)
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Glacial Lake Middletown, Newington deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Newington deltaic deposits - Highly collapsed ice-marginal delta deposits. Some noncollapsed delta surfaces remain at 50 m (165 ft) in southern part of unit and at 53 m (175 ft) in northern part. (Hartford South)
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Glacial Lake Middletown, Cromwell deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Cromwell deltaic deposits - Extensive ice-marginal deltaic deposits with surfaces at 44 to 47 m (145 to 155 ft) and topset-foreset contact at 41 m (135 ft) on western side of Connecticut River (projects to spillway at 33 m (107 ft)); deltas on eastern side of river, built slightly earlier, are at 50 to 56 m (165 to 185 ft) and have topset-foreset contacts at 45 m (149 ft) (projects to spillway at 37 m (120 ft)). Deltas in Cromwell have free fronts built into open water in glacial Lake Middletown basin. (Middletown, Hartford South, Glastonbury)
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Glacial Lake Middletown, Portland deltaic deposits - Ice-marginal deltas and fluviodeltaic deposits that record slowly lowering lake level (when adjusted for glacio-isostatic tilting) as ice margin retreated from Portland, Middletown, and Berlin northward to area near Windsor and East Windsor. See discussion of lake in accompanying text. Portland deltaic deposits - Successive ice-marginal deltaic deposits with surface altitudes of 47 to 50 m (155 to 165 ft); topset-foreset contacts exposed in several sand and gravel pits were measured at altitudes between 43 and 46 m (140 and 150 ft) (when projected, these reflect lowering at the spillway from 40 m (130 ft) to 37 m (120 ft )). (Middle Haddam)
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Glacial Lake Middletown, Lake-bottom deposits - Reddish brown, mostly varved silt and clay in couplets generally ranging from 5 to 10 cm (2 to 4 in) thick. Thickness and color of varves reflect annual deposition of beds while ice margin was in lake basin. Extensive deposits occur in basins of glacial Lakes Middletown and Berlin where section is up to 23 m (75 ft) thick. See discussion of lake in accompanying text.
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Glacial Lake Somers deposits - Successive ice-marginal deltaic and fluviodeltaic deposits built along eastern margin of Connecticut Valley ice lobe as it lay southeast of present Scantic River in Somers. Deposits are highly collapsed, especially on northwestern sides; noncollapsed parts in earlier morphosequences have deltaic surfaces at 87 to 90 m (285 to 295 ft) and fluvial surfaces that reach 111 m (365 ft). Later morphosequences have deltaic surfaces at 78 to 81 m (255 to 265 ft). Surfaces north of North Somers at 90 to 93 m (295 to 305 ft) may be from ice-hole deltas. Lake-bottom sediments occur at surface in front of 78-m (255-ft) deltas in southern part of unit. Water levels were controlled by spillway over ice-contact head of glacial Lake Ellington deposits (le). Spillway was eroded from about 87 m (285 ft) to 72 m (235 ft) during life of lake. (Hampden, Ellington)
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Glacial Lake Ellington deposits - Ice-marginal deltas with noncollapsed surfaces at 81 to 84 m (265 to 275 ft) near Sadds Mill and 84 to 87 m (275 to 285 ft) at and south of Ellington-Somers town line. Deposits grade southward to distal deltaic sand at Ellington village and lake-bottom sand and silt south of there. Spillway is not preserved but must have been over eastern margin delta deposits (lme) at about 72 m (235 ft). Meltwater discharging from this spillway cut terraces (ht) into glacial Lake Manchester (lma) and unit lme deposits farther south along Hockanum River valley, and built delta into glacial Lake Middletown (lmh). (Ellington)
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Glacial Lake Uncasville deposits - Ice-marginal deltas and fluviodeltaic deposits with deltaic surfaces at 17 to 20 m (55 to 65 ft) along Thames River and Poquetanuck Cove. Fluvial deposits on grade with deltas reach 29 m (95 ft) in tributary valleys. Coarse gravel fluvial deposits in lower Oxoboxo Brook valley reach 72 m (235 ft) and have very steep surface gradient to 20-m (65-ft) delta at Uncasville. Lake was ponded behind Ledyard moraine (hlm) and Jordan Cove - lower Thames River deposits (lcjl) in Thames River valley; sediment dam has largely been removed by postglacial Thames River entrenchment. (Uncasville, Montville, Norwich)
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Glacial Lake Quinebaug deposits - Successive ice-marginal deltaic and fluviodeltaic deposits and associated lake-bottom sediments. Delta-surface altitudes rise to the north from 47 m (155 ft) to 66 m (215 ft) due to glacio-isostatic tilting. Fluvial feeder deposits in tributary valleys reach as high as 87 m (285 ft). All deposits graded to single, stable lake level controlled by 41-m (134-ft) spillway over bedrock in narrow gorge where Quinebaug River turns westward, about 5 km (3 mi) south of Jewett City. Gorge probably was blocked by slightly older meltwater deposits (possibly by till); this led to establishment of drainage across adjacent 41-m (134-ft) bedrock saddle, which is about 21 m (70 ft) above present river level. Deposits of glacial Lake Quinebaug south of Quinebaug valley deposits (qb) are related to at least nine successive ice-marginal positions. Later deposits of unit lqb, north of unit qb in Blackwell Brook valley near Brooklyn, represent two successive ice-marginal deltas and associated lake-bottom deposits; altitudes of these deltas project to earlier glacial Lake Quinebaug water plane, probably due to erosion or collapse of unit qb deposits. (Jewett City, Plainfield, Danielson)
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Glacial Lake Connecticut, Stamford-Norwalk-Westport deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Stamford-Norwalk-Westport deposits - Ice-marginal fluviodeltaic deposits in lower reaches of Rippowam, Noroton, Fivemile, Norwalk, and Saugatuck Rivers. Consist of fluvial sediments in the valleys of Rippowam, Noroton, and Fivemile Rivers; deltaic deposits (represented by lcd) are entirely submerged offshore from Stamford and Darien. Fluvial sediments reach altitudes of 20 m (65 ft) in Norwalk River valley and 26 m (85 ft) in Saugatuck valley and grade southward to deltaic surfaces at 5 to 8 m (15 to 25 ft) at Norwalk and Westport; bulk of these deltas, represented by lcd, are submerged below present sea level. (Stamford, Norwalk South, Sherwood Point, Westport)
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Glacial Lake Connecticut, Stratford-Southport deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Stratford-Southport deposits-Fluvial deposits in Sasco Brook valley (as high as 26 m (85 ft)) grade to delta just west of Southport at 5 to 8 m (15 to 25 ft). Very coarse grained fluvial deposits in Mill River valley as high as 66 m (215 ft) grade southward to sandy delta in Fairfield at 5 to 8 m (15 to 25 ft). Fluvial deposits in Pequonnock River valley reach 26 m (85 ft) and grade to delta surface in Bridgeport at 5 to 11 m (15 to 35 ft). Ice-marginal fluvial deposits at 20 m (65 ft) in lower Housatonic River valley grade to delta in Stratford at 5 to 8 m (15 to 25 ft); these delta levels project to TRS at -14 to -15 m (-46 to -49 ft). (Westport, Bridgeport, Milford)
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Glacial Lake Connecticut, Lordship deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Lordship deposits - Ice-marginal delta with ice-contact slopes on both northeastern and northwestern sides. Surface altitude of delta is 8 to 11 m (25 to 35 ft); topset-foreset contact estimated at 5 m (15 ft) (Hokans, 1952); -12 m (-39 ft) projected to TRS. Built slightly earlier into somewhat higher lake level than Stratford-Southport deposits (lcss) and Devon-Milford deposits (lcdm) to the north. Delta is likely contemporaneous with large, submerged, ice-marginal lacustrine fan deposit that extends eastward from Lordship (lcf). Ice-margin position recorded by this delta marks interlobate angle between western Connecticut ice margin and Connecticut Valley ice lobe. Till overlying deltaic sediments on northeastern side provides some evidence of slight readvance of Connecticut Valley ice lobe from the northeast. (Bridgeport, Milford)
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Glacial Lake Connecticut, Devon-Milford deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Devon-Milford deposits - Ice-marginal fluvial deposits as high as 32 m (105 ft) in Beaver Brook valley grade southward to probable delta surface at 14 m (45 ft); distal end of this deposit was eroded by later meltwater in Housatonic River valley. Fluvial deposits in Wepawaug River valley with ice-contact head at 41 m (135 ft) and in Indian River valley at 32 m (105 ft) grade to delta surface in Milford at 8 to 11 m (25 to 35 ft); -15 m (-49 ft) projected to TRS. Ice-marginal deltaic deposits near Woodmont are at 8 to 11 m (25 to 35 ft). All deposits in this unit were built from ice-margin positions on western side of northeasterly retreating Connecticut Valley ice lobe. (Milford, Ansonia)
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Glacial Lake Connecticut, New Haven deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). New Haven deposits - Fluvial deposits in West River valley as high as 47 m (155 ft) and ice-marginal fluvial deposits in Mill River valley as high as 35 m (115 ft) grade southward to massive delta plain at 11 to 17 m (35 to 55 ft) in New Haven, West Haven, and Fair Haven. Topset-foreset contacts of delta, seen in excavation for Yale Bowl in West Haven and along railroad cut in Fair Haven, are at about 9 m (30 ft) and 7 m (22 ft), respectively; these levels project to TRS at -18 to -20 m (-59 to -66 ft). Deltaic sediments in New Haven overlie more than 61 m (200 ft) of lake-bottom sediment. (New Haven, Mount Carmel)
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Glacial Lake Connecticut, East Haven deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). East Haven deposits - Ice-marginal fluvial deposits in Farm River valley with ice-contact head at 32 m (105 ft) grade southwest to delta at East Haven with surface at 5 to 8 m (15 to 25 ft); -20 m (-66 ft) projected to TRS. (Branford, New Haven)
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Glacial Lake Connecticut, East River-West River deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). East River-West River deposits - Ice-marginal fluvial sediments at 23 m (75 ft) in West River valley grade southward to delta at Guilford with surface altitude of 5 to 8 m (15 to 25 ft); -16 m (-52 ft) projected to TRS. Ice-marginal fluvial sediments reach 17 m (55 ft) in East River and Neck River valleys and grade southward to deltas at Madison, north of Madison moraine (mom) and head of Hammonasset River-Menunketesuck River deposits (lchm), with surface altitudes at 5 to 11 m (25 to 35 ft). (Guilford)
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Glacial Lake Connecticut, Hammonasset River-Menunketesuck River deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd).Hammonasset River-Menunketesuck River deposits - Successive ice-marginal fluviodeltaic deposits. Fluvial sediments as high as 26 m (85 ft) in Menunketesuck River valley, 32 m (105 ft) in Indian River valley, and 17 m (55 ft) in Hammonasset River valley grade southward to deltas at Clinton with surface altitudes at 5 to 8 m (15 to 25 ft); -14 m (-46 ft) projected to TRS. Ice-marginal delta at Madison built along Madison moraine (mom) position has surface altitude of 5 m (15 ft); -14 m (-46 ft) projected to the spillway. Represents ice-marginal meltwater deposition graded to glacial Lake Connecticut following Hammonasset moraine (hlm) position and ending at Madison moraine (mom) position. (Clinton, Guilford, Essex)
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Glacial Lake Connecticut, Westbrook-Old Saybrook-Old Lyme deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Westbrook-Old Saybrook-Old Lyme deposits - Successive ice-marginal deltaic and fluviodeltaic deposits built at mouth of Connecticut River, in its tributary valleys of Black Hall and Lieutenant Rivers, and along present shoreline in Westbrook. Consist of deltas built at three major ice-margin positions. Ice-marginal deltas with surface altitudes of 5 to 8 m (15 to 25 ft; -12 m (-39 ft) projected to TRS) were built into glacial Lake Connecticut from Old Saybrook moraine (owm) position. Ice-marginal delta north of South Cove in Old Saybrook and fluviodeltaic deposits in Black Hall River valley in Old Lyme at 5 to 8 m (15 to 25 ft) were built from second ice position. Ice-marginal deltas in Westbrook and Old Saybrook and fluviodeltaic deposits in Lieutenant River valley in Old Lyme were built from Hammonasset moraine (hlm) position. These deltas are at 5 to 11 m (15 to 35 ft) (-13 to -15 m (-43 to -49 ft) projected to TRS). (Essex, Old Lyme)
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Glacial Lake Connecticut, Niantic deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Niantic deposits - Ice-marginal delta at mouth of Niantic River and ice-marginal fluviodeltaic deposits in Pataguanset River valley in East Lyme and in valleys of Threemile and Fourmile Rivers in Old Lyme were built from Old Saybrook moraine (owm) position; delta surfaces are at 8 to 11 m (25 to 35 ft), and well logs in Niantic village indicate topset-foreset contact is at about 1.2 m (4 ft) (-12 m (-39 ft) projected to TRS). In Bride Brook valley in East Lyme, coarse gravel fluvial deposits slope from 32 m (105 ft) with steep gradient to deltaic deposits at 8 to 11 m (25 to 35 ft) behind Old Saybrook moraine (owm) position; delta appears to be at glacial Lake Connecticut level, indicating that moraine did not exclude lake waters from mouth of valley. (Niantic, Old Lyme)
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Glacial Lake Connecticut, Jordan Cove-Lower Thames River deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Jordan Cove-Lower Thames River deposits - Ice-marginal fluviodeltaic deposits in Jordan Brook valley and several short tributaries to Long Island Sound were built from Old Saybrook moraine (owm) position. Scattered deltaic deposits along Thames River south of Ledyard moraine (hlm) position have surfaces at 8 to 14 m (25 to 45 ft); these levels are consistent with those projected for glacial Lake Connecticut. Only remnants of these deposits remain due to extensive dissection by later meltwater as level of glacial Lake Connecticut lowered; northern extent of large Thames River drainage basin contained distal meltwater flow for much longer period of time than did its smaller adjacent valleys such as Poquonock River. (Niantic, New London, Uncasville)
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Glacial Lake Connecticut, Poquonock River deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Poquonock River deposits - Ice-marginal fluviodeltaic deposits in Poquonock River valley; fluvial sediments as high as 32 m (105 ft) in upper valley and small tributaries grade southward to extensive delta with surface altitudes of 5 to 11 m (15 to 35 ft) south of Interstate Route 95 in Groton. Well logs indicate possible delta topset-foreset contact at 1 to 2 m (2 to 5 ft) altitude (-11 to -12 m (-36 to -39 ft) projected to TRS). (Uncasville, New London)
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Glacial Lake Connecticut, Mystic-Stonington deposits - Glacial Lake Connecticut deposits include both onland and offshore deposits; see discussion of lake in accompanying text. Spillway for glacial Lake Connecticut at "The Race" is abbreviated below as TRS. All onland deltas have offshore extensions, which are included in offshore submerged deltaic deposit (lcd). Mystic-Stonington deposits - Ice-marginal fluviodeltaic deposits in Mystic River, Copps Brook, Stony Brook, and lower Anguilla River valleys. Ice-marginal delta in lower Mystic River valley and fluviodeltaic deposits in small valleys to the east were built in association with Mystic moraine (mm) position; deltas have surfaces at 2 to 5 m (5 to 15 ft) and are mostly submerged below present sea level. Ice-marginal fluviodeltaic deposits in Mystic River valley head at Old Saybrook-Wolf Rocks moraine (owm) position. Fluvial sediments are at 20 m (65 ft) and grade to deltaic surfaces at 2 to 8 m (5 to 25 ft) in lower valley. Topset-foreset contact appears from well logs to be at sea level; this altitude projects to TRS at -9 to -10 m (-30 to -33 ft). (Mystic, Old Mystic)
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Uncorrelated deposits of ice-dammed ponds
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Cobble Brook deposits - Four successive ice-marginal deltaic deposits in and adjacent to small valley on eastern side of Housatonic River. Deltas are mostly graded to 175-m (575-ft) spillway at head of valley. Low-lying deposits well below level of spillway were extensively collapsed. (Ellsworth, Kent)
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Bantam River deposits - Series of ice-marginal deltas along Bantam River valley. Controlled by spillways at 239 m (785 ft) and 236 m (775 ft) at southwestern end and perhaps by some temporary higher spillways along edge of ice. Represents ice margin parallel to that of Mallory Brook deposits (ml), lower in Bantam River drainage so that numerous higher spillways of unit ml could no longer be used. (New Preston, Litchfield)
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Mallory Brook deposits - Series of ice-marginal deltas along southeastern sides of Bantam River and Mallory Brook valleys. Controlled by six spillways ranging from 306 m (1,005 ft) down to 181 m (595 ft). (New Preston, Litchfield)
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Woodbury deposits - Ice-marginal deltas in uplands east of Pomperaug River. Controlled by 236-m (775-ft) to 206-m (675-ft) spillways. Immediately succeeded by ice-marginal deltas perched on eastern side of river valley, controlled by 163-m (535-ft) to 102-m (335-ft) spillways. (Woodbury)
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Southbury deposits - Ice-marginal deltas in northwest-sloping valley on eastern side of Pomperaug River valley. Ponding initially controlled by 142-m (465-ft) spillway across Eightmile Brook deposits (eb) to the southeast. Successive levels controlled by three side-valley spillways to the southwest at 120 m (395 ft), 108 m (355 ft), and 102 m (335 ft). (Southbury)
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Still River-Saugatuck River divide deposits - Ice-marginal deltas in three valleys that slope northward from Still River-Saugatuck River drainage divide. Level of ponding in each valley controlled by spillway across divide. Successive deltas in Limekiln Brook valley were controlled by 169-m (555-ft) spillway; one delta in Wolf Pit Brook valley was controlled by 197-m (645-ft) spillway; successive deltas in Sympaug Brook valley were controlled by 126-m (415-ft) spillway that also served as glacial Lake Danbury-Saugatuck River divide stage outlet. (Danbury, Bethel, Newtown, Botsford)
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Pootatuck River-Pequonnock River divide deposits - Ice-marginal deltas in several valleys (including Pootatuck River) that slope northward from divide. Levels of ponding in Hurds Brook valley controlled by successively lower spillways at 157 m (515 ft), 154 m (505 ft), 136 m (445 ft), and 126 m (415 ft). Levels of ponding in two small tributary valleys to Halfway River controlled by two spillways at 126 m (415 ft) and 117 m (385 ft). Small pockets in upper reaches of Pootatuck River basin controlled by local spillways across divide at 157 m (515 ft) to 130 m (425 ft). (Newtown, Botsford, Long Hill)
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Tolles-Terryville deposits - Ice-marginal deltas ponded in small upland valleys on eastern side of Naugatuck River. Deposits near Tolles were controlled by spillways at 276 m (905 ft) and 242 to 206 m (795 to 675 ft) between Naugatuck River tributaries. Deposits near Terryville are in Poland River basin and controlled by a spillway at 203 m (665 ft) into Naugatuck River tributary. Ponding in these valleys controlled by ice positions at or near interlobate angle between western side of Connecticut Valley ice lobe and western upland ice margin. (Thomaston)
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East Mountain Reservoir deposits - Ice-marginal deltas ponded in west-sloping tributaries of Naugatuck River. Controlled by multiple spillways across valley divides at altitudes ranging from 221 m (725 ft) to 126 m (415 ft). Sequential ponding in these valleys controlled at interlobate angle between western side of Connecticut Valley ice lobe and western upland ice margin. (Waterbury, Naugatuck)
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Bethany deposits - Ice-marginal deltas ponded at multiple stages in four west-sloping tributaries of Naugatuck River. Spillways cross local divides between tributaries between 59 m (195 ft) and 194 m (635 ft). Sequential ponding in these valleys required ice-margin positions with strong north-northeast to south-southwest trend. (Naugatuck)
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West Branch Salmon Brook deposits - Ice-marginal deltas ponded at several levels in headwaters and tributaries of eastward-flowing West Branch Salmon Brook by western margin of Connecticut Valley ice lobe. Highest group of deposits is graded to spillways above 305 m (1,000 ft). A slightly younger group of deposits has spillways between 270 and 198 m (885 and 650 ft). Lowest group was impounded behind Barndoor Hills and graded to spillways at 126 m (415 ft), 117 m (385 ft), and 102 m (335 ft). (Tariffville, New Hartford)
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Onion Mountain deposits - Ice-marginal deltas in small north-sloping pockets east and north of Onion Mountain. Deposits are highly collapsed; only narrow fringes of noncollapsed deltaic surfaces are present. Deposits were ponded against scarp of Western Highlands by Connecticut Valley ice lobe and graded to three local spillways at 209 m (685 ft), 181 m (595 ft), and 160 m (525 ft). (Avon, Tariffville, Collinsville)
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Burlington deposits - Ice-marginal deltas ponded high against edge of Western Highlands by Connecticut Valley ice lobe. Delta surfaces are successively lower to northeast and were controlled by succession of lower spillways between 288 m (945 ft) and 181 m (595 ft) across Burlington Brook-Pequabuck River drainage divide. (Collinsville)
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Whigville deposits - Ice-marginal deltas ponded against collapsed slope of higher level glacial Lake Bristol deposits (lbr). Graded to two spillways at 120 m (395 ft) and 127 m (415 ft). As ice margin retreated, the lake at Whigville at 127 m (415 ft) drained; meltwater that continued to spill from Burlington lakes eroded parts of Whigville deltas. (Bristol)
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Quinnipiac River-Mill River divide deposits - Ice-marginal deltas ponded in four north-draining valleys tributary to Quinnipiac River. In Tenmile River valley, deltaic surfaces are at 63 to 66 m (215 to 225 ft) and are graded to 59-m (195-ft) spillway across divide. In valley of unnamed tributary to Tenmile River, deltaic surfaces reach 62 m (205 ft) and were controlled by 56-m (185-ft) spillway. In Honeypot Brook valley, esker-fed delta has surface altitude of 63 to 69 m (205 to 215 ft) graded to 59-m (195-ft) spillway. In Broad Brook valley, there are two successive deposits; older delta has extensive collapsed ice-marginal parts south of Broad Brook Reservoir, but small noncollapsed delta surfaces at 78 m (255 ft) remain; ponding controlled by a 75-m (245-ft) spillway; younger delta north of reservoir has surface at 72 m (235 ft), controlled by 66-m (215-ft) spillway. Extensive collapsed ice-marginal parts of this deltaic sequence, including a 2-km-long (1.5-mi-long) feeder esker, block northern end of Quinnipiac Gorge and probably contributed to damming of glacial Lake Southington. (Southington, Meriden, Mount Carmel, Wallingford)
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Mount Sanford ridge deposits - Ice-marginal deltas in high-level pockets in several northeast-sloping valleys that drain ridge extending north and south from Mount Sanford. Level of deposits was controlled in each valley by lowering succession of spillways that resulted from northeastward retreat of western margin of Connecticut Valley ice lobe. Spillway altitudes range from 197 m (645 ft) down to 50 m (165 ft). (Mount Carmel)
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Somers high-level deposits - Ice-marginal deltas in several pockets graded to local spillways that lower successively to the west from 247 m (810 ft) down to 148 m (485 ft). Ice-marginal deltaic deposits in Monson, Mass., were graded to lacustrine deposits in this series with spillway at 215 m (705 ft) east of Perkins Mountain. (Hampden)
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Shenipsit Lake deposits - Ice-marginal delta at 168 m (550 ft) overlying as much as 21 m (70 ft) of lake-bottom sand and silt just south of Shenipsit Lake. Deposit was ponded by ice margin to the west and north and controlled by a spillway over older upper Connecticut River divide deposits (cd) that probably contained buried ice. North of Shenipsit Lake, deposits reach 209 m (685 ft), but have no recognizable spillway and are mostly collapsed from former levels. Deposits south of Crystal Lake straddle the eastern upper Connecticut drainage divide and were deposited from ice-margin positions east of divide by meltwater flowing southwest through local spillways. (Rockville, Ellington)
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Wapping deposits - Ice-marginal deltas ponded in two pocket valleys against eastern upland before opening of glacial Lakes Middletown and Hitchcock in this area. Higher deposit was graded to two spillways at 84 m (275 ft) and 81 m (265 ft). Lower deposit has a terrace form and was ponded along ice margin and controlled by 56-m (185-ft) spillway between bedrock hills to the east. (Manchester)
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Vernon-Lydallville deposits - Successive ice-marginal deltas ponded against Eastern Highlands; slightly younger and lower in altitude than northern part of upper Connecticut River divide deposits (cd). Most of these deposits are highly collapsed but some delta surfaces remain, graded to lowering successive ponding controlled by spillways from 172 m (565 ft) down to 105 m (345 ft). (Rockville)
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Upper Connecticut River divide deposits - Ice-marginal deltaic deposits built into four upland lakes, impounded by eastern margin of Connecticut Valley ice lobe; lakes spilled through saddles at 154 m (505 ft), 197 to 200 m (645 to 655 ft), 187 m (615 ft), and 239 m (785 ft) across eastern part of upper Connecticut River drainage divide. Southernmost lake in this unit was previously named glacial Lake Dickinson (Langer, 1977). (Glastonbury, Rockville)
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Hanging Hills deposits - Series of ice-marginal deltas in three valleys that drain northeastern slope of Hanging Hills. In Mattabesset River valley and its headwater tributaries, spillway altitudes lower northward from 114 m (375 ft) down to 53 m (175 ft). In Hatchery Brook valley, spillway altitudes range from 96 to 56 m (315 to 185 ft). In both valleys, deltaic surfaces are lower to the north, each graded to a lower spillway. In the Belcher Brook valley, deltaic surfaces are at 56 to 59 m (185 to 195 ft) and are graded to 50-m (165-ft) spillway south of Beaver Pond. (Meriden)
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Coginchaug River divide deposits - Ice-marginal deltas ponded in four pocket valleys against Coginchaug River divide soon after ice margin retreated northward across it. Each delta was controlled by a spillway across the divide. Further retreat into the basin resulted in development of glacial Lake Coginchaug, represented by Durham stage deposits (lcgd) and Middletown stage deposits (lcgm), which spilled across divide at lower altitude. (Durham)
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West Haddam deposits - Series of ice-marginal deltas ponded in small northeast-draining tributaries to Connecticut River. Spillways range from 172 m (565 ft) down to 102 m (335 ft) across local divides. Deposition of these small, high-level deltas in successively lower positions to the northeast was due to lobation of ice margin in lower Connecticut River valley; western side of this lobe retreated to the northeast. (Haddam)
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Moodus River divide-Pine Brook deposits - Small ice-marginal deltas in northwest-sloping tributary valleys to Moodus River. Oldest deltas in each valley were graded to spillways at 108 m (355 ft), 114 m (375 ft), and 142 m (465 ft) across the southern Moodus River divide. Successive lower deltas in each valley were graded to lower spillways across smaller valley divides. Relatively extensive ice-marginal deltas in Moodus Reservoir valley and at southern end of Pine Brook valley have surface altitudes at 123 to 126 m (405 to 415 ft) and were built into small, open lake that spilled eastward over 120-m (395-ft) spillway across Moodus River divide. Unlike most deltas in this type of depositional system, these have free fronts, and lake-bottom surfaces may underlie areas now flooded by Moodus Reservoir. Deposits in north-draining Pine Brook valley, north of Babcock Pond, are series of three ice-marginal deltas graded to 117-m (385-ft) spillway that cuts through 128-m (420-ft) ice-marginal head of delta south of Babcock Pond. This lower ponding could not occur until ice margin retreated out of Moodus River valley and lake in Moodus Reservoir valley drained westward down Moodus River valley. (Moodus, Deep River)
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Judd Brook-Gillette Brook deposits - Three ice-marginal deltas built in lowering succession in Judd Brook valley graded to spillways at 155 m (510 ft), 139 m (455 ft), and 126 m (415 ft). Three successive ice-marginal deltas in Gillette Brook valley east of glacial Lake Colchester graded to spillways at 160 m (525 ft), 157 m (515 ft), and 130 m (425 ft). (Colchester)
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Colchester deposits - Two successive ice-marginal deltaic deposits that cross present drainage divides between upper Deep River and Lake Hayward Brook. Relationship between deposits and topography indicates that former divides were at narrows at south ends of the two deposits; divides were shifted northward after deltas were built. (Colchester)
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Beaver Brook deposits - Successive ice-marginal deltaic deposits with surfaces at 29 to 47 m (95 to 155 ft) that cross present divide between Beaver Brook and Falls Brook. Initial spillway must have been across rock ridge south of Uncas Pond, but present altitude of lowest col is too low to have controlled deposits; detached ice blocks must have been present in area. Upper Cedar Pond Brook valley at northeastern end of deposit was ice free and contains fluvial feeder deposits up to 69 m (225 ft) on grade to deltaic surfaces south of Cedar Lake. (Hamburg, Old Lyme)
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Mashapaug Pond deposits - Ice-marginal deltas built into series of small lakes ponded against upper Quinebaug River-Shetucket River drainage divide at five successively lower spillways across divide at altitudes of 294 m (965 ft), 276 m (905 ft), 267 m (875 ft), 255 m (835 ft), and 215 m (705 ft). Deposits are particularly rusty because of abundance of sulfitic schist fragments. (Wales, Westford)
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Conant Brook-Roaring Brook deposits - Ice-marginal deltas built into two groups of small lakes on eastern side of Willimantic River. Deposits in Conant Brook valley were controlled by successively lower local spillways at 219 m (720 ft), 203 m (665 ft), and 175 m (575 ft). Deposits in Roaring Brook valley were controlled by spillways across divide between two valleys at 655 ft (200 m), 635 ft (194 m), 615 ft (187 m), and 535 ft (163 m). (Stafford Springs, South Coventry)
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Cedar Swamp area deposits - Successive ice-marginal deltaic deposits in Cedar Swamp valley and in north-draining tributaries to Eagleville Brook valley, Conant Brook valley, and small tributary valleys on eastern side of Willimantic River. Earliest deposits in Cedar Swamp valley contain extensive ice-channel fillings and were controlled by 169-m (555-ft) spillway; these deposits blocked the valley. Successive deposits north of Cedar Swamp were controlled by 178-m (585-ft) spillway. (South Coventry)
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Fitchville deposits - Ice-marginal deltas in seven north-draining tributaries to Yantic River; single deltas in each valley were controlled by spillways across each local divide. (Fitchville, Norwich)
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Gardner Lake lacustrine deposits - Successive ice-marginal deltaic deposits in north-draining Deep River valley and in Gardner Brook valley where deposits bury former divide. Deltaic deposits north of Gardner Lake have surface altitudes of 123 to 126 m (405 to 415 ft) and were built into small lake controlled by 120-m (395-ft) spillway. Deltas in Deep River valley, including one near-ice-marginal delta, have surface altitudes of 130 m (425 ft) and were built into small lake controlled by 127-m (415-ft) spillway across divide at The Wales. Slightly lower deltas on northern side of Deep River Reservoir are extensively collapsed and were controlled by 117-m (385-ft) spillway across deposits occupying divide area north of Gardner Lake. (Fitchville, Colchester)
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Ledyard deposits - Ice-marginal deltas in three north-draining tributaries to Thames River. Deltas with surfaces at 50 to 60 m (165 to 185 ft) in Billings Avery Brook valley contain numerous well-developed kettles and were controlled by two spillways that cross Ledyard moraine (hlm) and head of Groton deposits (gr) at 53 m (175 ft) and 47 m (155 ft). Deltas in Joe Clark Brook and Shewville Brook valleys to the north were controlled by three local spillways at 53 m (175 ft), 47 m (155 ft), and 38 m (125 ft). (Uncasville)
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North Thompson deposits - Ice-marginal deltas with esker feeder deposits in two north-sloping tributary valleys. Eastern valley is tributary to Fivemile River valley and has delta surfaces at 157 m (515 ft), controlled by 151-m (495-ft) spillway across divide; western valley is tributary to French River valley and has two successive deltas at 154 m (505 ft) and 151 m (495 ft), controlled by 145-m (475-ft) spillway. (Webster, Oxford)
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East Putnam-Glocester deposits - Successive ice-marginal deltas in northwest-sloping Cady Brook and Mary Brown Brook valleys. Series of ponds began in Glocester, R.I., controlled by two spillways across Quinebaug River divide; first spillway is in Rhode Island, second spillway at 178 m (585 ft) is in Connecticut. Later spillways for ponding in Connecticut descend from 142 m (465 ft) to 130 m (425 ft). (Thompson)
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White Brook deposits - Four successive ice-marginal deltas in White Brook valley; deposits are extensively collapsed. Series of ponds controlled by spillways at 93 m (305 ft), 90 m (295 ft), and 84 m (275 ft) across local divide. (Danielson)
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Mashentuck Brook deposits - Ice-marginal deltas in north-draining Mashentuck Brook valley. Ponding controlled by two spillways at 130 m (425 ft) and 123 m (405 ft). (East Killingly)
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Wauregan deposits - Three successive ice-marginal deltaic and deltaic-fluvial deposits in north-sloping tributary valley to Quinebaug River. Ponding was controlled by two 69-m (225-ft) spillways across southern divide. Highly collapsed deposits that reach 87 m (285 ft) in northern part of unit are chiefly fluvial. (Danielson, Plainfield)
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Mill Brook deposits - Four successive ice-marginal deltas in north-draining Mill Brook valley. Sediment was deposited around numerous stagnant ice blocks. Levels of ponding were controlled by spillways at 53 m (175 ft) and 50 m (165 ft) across divide at southern end of unit. (Plainfield, Jewett City)
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Broad Brook deposits - Two successive ice-marginal deltas in lower part of north-draining Broad Brook valley. Level of ponding was controlled by 50-m (165-ft) spillway across local divide. (Jewett City)
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Bay Mountain deposits - Successive ice-marginal deltas related to nine ice-margin positions in three relatively steep, north-sloping valleys in Bay Mountain upland area. Eastern valley occupied by Billings Brook contains most extensive deposits and is tributary to Pachaug River basin. Earliest and highest levels of ponding in this system controlled by spillway at 99 m (325 ft) across Quinebaug River basin divide; some later levels controlled by spillways across local divides, but downstream from these, path of meltwater flow was across basin divide through 69-m (225-ft) spillway. (Jewett City, Old Mystic)
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Uncorrelated deposits of sediment-dammed ponds
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Salisbury deposits - Ice-marginal fluvial deposits reach as high as 230 m (755 ft) in northern part of unit; grade southward to ponded sediments in Salisbury village area. Near-ice-marginal fluviodeltaic deposits built from the west overlie lake-bottom deposits at Lakeville. Ponding probably was in overdeepened bedrock basin behind Salmon Creek narrows at southern end of unit. (Bashbish Falls, Sharon)
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Housatonic River deposits from New Milford to West Cornwall - Sequential ice-marginal deltaic and fluviodeltaic deposits along Housatonic River between New Milford village and West Cornwall; fluvial feeder deposits in some steeper tributary valleys to Housatonic River. Numerous ice-margin positions identified, although deposits in many places are only discontinuous remnants due to extensive distal-meltwater and postglacial erosion. Deltaic surfaces are at 81 m (265 ft) at southern end of unit and 184 m (605 ft) at northern end; shingled-profile breaks identified in many places in association with ice-margin positions. Ponding in this part of valley began immediately following drainage of last stage of glacial Lake Danbury; initial impoundment was behind glacial Lake Danbury deposits. (New Milford, Kent, Dover Plains, Ellsworth, Cornwall, South Canaan)
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Housatonic River deposits from Stratford to Shepaug River - Discontinuous remnants of sequential ice-marginal deltaic deposits along Housatonic River between Stratford and mouth of Shepaug River in Southbury. Surface altitudes at 17 m (55 ft) at southern end of unit rise with minor identifiable shingled-profile breaks to 78 m (255 ft) at northern end of unit. Deposits were considerably incised by later meltwater and postglacial erosion so that reconstruction of surface gradients, ice-margin positions, and delta surfaces is precluded. Initial ponding in valley began directly following deposition of Stratford-Southport deposits (lcss) into glacial Lake Connecticut at mouth of valley. (Milford, Ansonia, Long Hill, Southbury, Newtown)
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Shepaug River deposits - Largely discontinuous remnants of sequential ice-marginal deltaic deposits along lower Shepaug River. Probably related to at least three ice-marginal positions with levels of ponding between 72 m (235 ft) and 84 m (275 ft). Initial ponding behind last deposits of Housatonic River (hrs) in Housatonic River valley. (Roxbury, Newtown)
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Eightmile Brook deposits - Several ice-marginal deltaic and fluviodeltaic deposits in Eightmile Brook and Little River valleys; northern sequences have extensive fluvial sections. Initial ponding in southern part of unit was behind till and (or) bedrock spillway on side of valley; successive sequences controlled by sediment-dammed ponding. Meltwater deposits also spilled southeast into upper part of Little River valley. (Southbury)
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Pequonnock River-Farmill River deposits - Ice-marginal and near-ice-marginal fluviodeltaic and deltaic-fluvial deposits in upper reaches of Mill, Pequonnock, and Farmill River valleys and their tributaries. Ponding in many places was in overdeepened basins behind bedrock narrows; in other places, such as at Stepney in Pequonnock River valley, sequential ponding was behind successive ice-contact heads in valley. Meltwater construction of this system in upper reaches of these valleys closely followed construction of fluviodeltaic Stratford-Southport deposits (lcss) that graded to glacial Lake Connecticut in lower reaches of valleys. (Botsford, Long Hill, Bridgeport)
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Saugatuck River-Aspetuck River deposits - Near-ice-marginal fluviodeltaic and deltaic-fluvial deposits in upper Saugatuck River valley and tributary Aspetuck River valley. Initial ponding was behind head of Stamford-Norwalk-Westport deposits (lcsnw) at Westport; subsequent ponding was mostly in wider basins behind bedrock narrows with only minor sediment damming. Deposits in West Branch Saugatuck River valley included in this unit are largely fluvial, but southern part may have been tributary feeder to deltaic deposits at Saugatuck River valley confluence. (Botsford, Norwalk North, Westport, Norwalk South, Sherwood Point)
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Upper Norwalk River deposits - Sequential near-ice-marginal fluviodeltaic deposits in upper Norwalk River and Silvermine River valleys. Fluvial deposits in narrower and steeper sections of valleys grade to deltaic deposits ponded in overdeepened basins behind bedrock narrows; successive northward construction of this depositional system indicated by distribution of textures within deposits rather than shingled-surface profiles. (Bethel, Norwalk North)
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Rippowam River-Noroton River deposits - Sequential near-ice-marginal fluviodeltaic deposits in Rippowam and Noroton River valleys. Fluvial deposits in narrower and steeper sections of valleys grade to deltaic and lacustrine deposits in deeper basins near Interstate Route 95. Successive northward construction within this unit indicated by textural distribution rather than shingled-surface profiles. (Pound Ridge, Stamford)
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Naugatuck River deposits from Thomaston to Litchfield - Near-ice-marginal fluviodeltaic deposits in southern half of unit. Ponded initially behind head of Naugatuck River deposits from Naugatuck to Reynolds Bridge (nrn) at about 122 m (400 ft). Ice-marginal fluvial deposits of very coarse gravel at northern end of unit reach 152 m (500 ft) and grade southward to deltaic deposits at 133 m (435 ft) just north of Thomaston Dam. (Thomaston)
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Naugatuck River deposits from Naugatuck to Reynolds Bridge - Sequential ice-marginal deltaic and fluviodeltaic deposits and near-ice-marginal fluviodeltaic deposits in Naugatuck River from Naugatuck northward to Reynolds Bridge. Earliest deposits in this unit are fluviodeltaic deposits built in two tributary valleys to Naugatuck River (Beacon Hill Brook from east and Long Meadow Pond Brook from west). Early levels of ponding at 96 m (315 ft) must have been controlled by drift and (or) ice in narrow bedrock gorge of Naugatuck River south of unit. Inset against higher ponded deposits in main valley at Naugatuck are deltaic deposits at 81 m (265 ft). Delta surfaces rise northward through this section of valley to 120 m (395 ft), a gradient of about 1.5 m/km (8 ft/mi) (0.8 m/km (4 ft/mi) when postglacial tilt is taken into account). (Thomaston, Waterbury, Naugatuck)
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Mad River deposits - Ice-marginal and near-ice-marginal fluviodeltaic deposits in Mad River valley built from ice both in upper Mad River and along Naugatuck River. Initial spillway at 136 m (445 ft) across East Mountain Reservoir deposits (emt) in Hopeville Brook valley. Later spillway across earlier head at Mill Plain controlled ponding levels in northern part of unit at about 137 m (450 ft). (Waterbury, Southington)
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Naugatuck River deposits from Derby to Beacon Falls - Ice-marginal and near-ice-marginal fluviodeltaic deposits in Naugatuck River valley from confluence with Housatonic River northward to Beacon Falls. Fluvial feeder deposits reach 72 m (235 ft) in short tributary valleys and grade to deltaic deposits in main valley. Levels of ponding recorded in deltas are about 30 m (100 ft) at southern end of unit and about 61 m (200 ft) at Beacon Falls, a rise of approximately 1.9 km/km (10 ft/mi) (1.2 m/km (6 ft/mi) when postglacial tilt is taken into account). (Naugatuck, Ansonia)
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Barkhamsted Reservoir deposits - Highly collapsed deposits south of Saville Dam. Maximum altitudes reach 149 m (490 ft) and probably are deltaic, ponded behind 152-m (500-ft) upper Farmington River deposits (fu) south of Puddle Town. North of Saville Dam, only scattered probable deltaic surfaces are visible above reservoir water level; altitudes are at 172 m (565 ft) and reach 178 m (585 ft) at ice-margin position just north of Barkhamsted town line. North of this position, deposits with surfaces at 166 m (545 ft) rise northward to 181 m (595 ft). North of reservoir, presumably fluvial deposits with 198-m (650-ft) surfaces continue on steep gradient into Massachusetts. (New Hartford)
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Southwick-Suffield deposits - Successive ice-marginal deltaic deposits with delta surfaces at 78 to 81 m (255 to 265 ft); initial spillways were over heads of deposits of glacial Lake Tariffville (lt). Deposits continue northward into Massachusetts where massive ice-marginal deltas surrounding Congamond Lakes have surfaces that reach 84 m (275 ft). (Tariffville, Southwick, West Springfield)
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Upper Farmington River deposits - Ice-marginal deltaic deposits in upper Farmington River valley that were highly dissected by later meltwater and by Farmington River. Remaining terraces are between Collinsville and New Hartford. The 152-m (500-ft) delta south of Puddle Town extends across valley. From New Hartford northwest along West Branch Farmington River, surfaces rise on rather steep gradient and are predominantly fluvial with possible deltaic portions in Hartland. (Collinsville, New Hartford, Winsted)
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Simsbury deposits - Successive ice-marginal deltaic deposits built in part against stagnant ice along narrow valley of present Farmington River, resulting in collapsed distal deltaic sands southwest of Simsbury village. Older deltaic surfaces reach 102 m (335 ft), younger surfaces are at 90 m (295 ft). As much as 50 m (165 ft) of lake-bottom silt and clay underlies Farmington River alluvium. Levels of ponding were controlled by massive ice-contact head of glacial Lake Farmington deposits (lf) that blocked valley to the south at maximum altitude of 84 m (275 ft). (Tariffville, Avon)
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West Simsbury deposits - Ice-marginal deltaic and fluviodeltaic deposits. Westernmost deposits in Avon quadrangle at 93 to 111 m (305 to 365 ft) are mostly fluvial. Slightly younger deposits to the east are successively ponded deltaic sediments rising 87 m (285 ft) in northern Avon to 102 m (335 ft) northward into Simsbury. In Tariffville quadrangle, consists of highly collapsed remnants of ice-contact head and narrow fluvial terrace that reaches 110 m (360 ft) at north end. (Avon, Tariffville)
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Unionville deposits - Fluvial deposits in Bristol. Distal sands overlie gravelly ice-marginal head of Southington-Bristol deposits (sb) at East Bristol; this fluvial morphosequence rises northward to ice-contact head in southeastern corner of Burlington near Lake Como with nearly 3 km (2 mi) of esker feeders. Behind this head, consists of deltaic deposits near Lake Garda; these have an ice-marginal head at 99 to 105 m (325 to 345 ft) along southwestern side of Farmington River. On northeastern side of river, scattered remnants of ice-contact deposits remain near Unionville and range from 96 to 114 m (315 to 375 ft); these are probably deltaic, built in and around stagnant ice while meltwater still escaped southwestward via Unionville Brook-Cherry Brook valley. North of river, six or seven eskers descend down southwestern slope towards river and are some of the few examples of southward-sloping eskers in Connecticut; may have been built in subglacial tunnels or collapsed down onto southward-sloping till surface from high in the ice. (Bristol, Collinsville, Avon)
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Upper Mill River deposits - Predominantly successive ice-marginal deltaic deposits. Surface gradient over whole unit is relatively gentle, rising from 35 to 59 m (115 to 195 ft) with head at West Cheshire reaching 67 m (220 ft). Deposits were initially ponded behind bedrock narrows at Mount Carmel and head of New Haven deposits (lcnh). Ponding continued as ice retreated northeastward because of blockage by at least two ice-contact heads, first near Hamden-Cheshire town line and second at West Cheshire. (Mount Carmel)
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Southington-Bristol deposits - Successive ice-marginal deltas, several of which have esker feeders in Eightmile River and Patton Brook, tributary valleys to Quinnipiac River. Delta surfaces rise from 69 m (225 ft) to 78 m (255 ft) in the Eightmile River valley and to 75 m (245 ft) in Patton Brook valley. Deltas were ponded behind heads of last deltas built into open glacial Lake Southington. (Bristol, New Britain, Southington, Meriden)
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Upper Farm River-Muddy River deposits - Two successive fluviodeltaic morphosequences in upper Farm River valley: the first was ponded behind the 34-m (110-ft) ice-marginal head of East Haven deposits (lcenh) and surfaces rise from 29 m (95 ft) to head at 53 m (175 ft); ponding occurred behind this head also, and surfaces rise from 50 m (165 ft) up to 61 m (200 ft) northeast of Northford. Deposits in Muddy River valley consist of probably three successive fluviodeltaic deposits; fluvial sediments predominate and are graded to less extensive deltaic sediments north of valley narrows. (Branford, Wallingford)
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Upper Wepawaug River deposits - Mostly fluvial sediments with ponded sediments occurring at southern end of unit around Wepawaug Reservoir. Ponding was caused by presence of ice to the southeast. Western margin of Connecticut Valley ice lobe provided dam as well as feeding meltwater streams for this unit. (Ansonia)
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Dividend Brook deposits - Successive ice-marginal deltas with surface altitudes of 47 to 50 m (155 to 165 ft) in southern part of unit and 53 to 56 m (175 to 185 ft) in northern part. Topset-foreset contact in Mustard Bowl pit just north of Cromwell-Rocky Hill town line is estimated at 44 to 45 m (146 to 149 ft). Deltas built into a small glacial lake that was temporarily ponded to a slightly higher level than glacial Lake Middletown behind ice-marginal deltas of Cromwell delta deposits (lmc) and before that sector of the ice margin retreated north of Cedar Mountain; water level was controlled by Dividend Brook spillway across delta surface of Cromwell delta deposits (lmc) and lowered from about 46 m (150 ft) to 40 m (129 ft) during the life of the Dividend Brook lake. (Hartford South, Glastonbury)
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Upper Hammonasset River deposits - Series of probably four ice-marginal and near-ice-marginal fluviodeltaic morphosequences in upper Hammonasset River valley. Morphosequence deposition was controlled by topographic basins along valley separated by bedrock narrows formerly occupied by sediment dams. Surface altitudes over unit as a whole range from 84 m (275 ft) northward to 98 m (320 ft); ice-margin positions are recorded in two places by slight increases in surface altitudes and coarser materials; behind each position, sediments are finer and altitudes slightly lower. (Durham, Haddam)
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Hammonasset River deposits - Ice-marginal deltas initially ponded behind head of Hammonasset River - Menunketesuck River deposits (lchm) in lower Hammonasset River valley. Near-ice-marginal fluviodeltaic sequence in northern part of unit; fluvial deposits reach 46 m (150 ft) in Chatfield Hollow valley and grade southward to deltaic surfaces at 26 m (85 ft). (Clinton)
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Quonnipaug Lake-East River-West River deposits - Series of near-ice-marginal fluviodeltaic deposits, initially ponded behind heads of East River-West River deposits (lcew) in lower parts of East and West Rivers. To the north, ponding occurred in topographic basins behind sediment-filled bedrock narrows. Predominantly fluvial sediments occur in steep, narrow sections of East and West Rivers. (Durham, Guilford)
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Upper Branford River deposits - Series of ice-marginal fluviodeltaic deposits. Ponding occurred mostly in topographic basins behind sediment-filled bedrock narrows. (Branford, Guilford)
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Westbrook-Old Saybrook deposits - Ice-marginal deltaic and fluviodeltaic deposits in upper Patchogue and Oyster River valleys and their tributaries. Ponded initially behind Westbrook-Old Saybrook-Old Lyme deposits (lcwoo). Fluvial feeders reach 18 to 21 m (60 to 70 ft) altitude; deltaic surfaces at 11 to 14 m (35 to 45 ft). (Essex)
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Lower Connecticut River (Essex-Hamburg-Deep River) deposits - Predominantly ice-marginal deltaic deposits of which only remnants remain due to downcutting by postglacial Connecticut River. Delta surfaces are at 11 m (35 ft) in southern part of unit and 14 to 17 m (45 to 55 ft) in northern part. Near-ice-marginal fluviodeltaic sequence in Joshua Creek valley in Lyme has fluvial surfaces that reach 21 m (70 ft) and grade to 14-m (45-ft) delta surface along Connecticut River. Initial ponding in lower Connecticut River valley was behind Westbrook-Old Saybrook-Old Lyme deposits (lcwoo) at mouth of river. (Hamburg, Old Lyme, Essex, Deep River)
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Lower Connecticut River (Chester-Hadlyme) deposits - Near-ice-marginal fluviodeltaic deposits in Pattaconk Brook-Chester Creek valley in Chester, in Roaring Brook-Whalebone Creek valley in Hadlyme, and along Connecticut River. Fluvial deposits with surfaces as high as 30 m (100 ft) in Chester and 38 m (125 ft) in Roaring Brook valley in Hadlyme grade eastward and westward, respectively, to deltaic surfaces on either side of Connecticut River valley at 17 to 20 m (55 to 65 ft). Ponding to this level in Connecticut River valley was due to blockage by sediment dams to the south formed by Westbrook-Old Saybrook-Old Lyme deposits (lcwoo) and Essex-Hamburg-Deep River deposits (lce). Also included are small, near-ice-marginal fluviodeltaic morphosequences in upper sections of Hemlock Valley Brook, Hungerford Brook, and Roaring Brook valleys in Hadlyme. Each deposit occupies topographic basin in the valley and is graded to local tributary-valley spillway at its southern end; each spillway is somewhat higher than present stream gradient through valley narrows; present stream courses were probably blocked by till (or possibly buried ice) at time of meltwater deposition. (Deep River)
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Lower Connecticut River (Tylerville-Portland) deposits - Predominantly ice-marginal deltaic deposits; probably more successive morphosequences exist than are indicated by ice-margin position symbols on map. From Tylerville to north of Haddam-Middletown town line, deltaic surfaces rise from 23 m (75 ft) to 34 m (110 ft) (a gradient of about 1.2 m/km (6 ft/mi), most of which can be accounted for by postglacial uplift); fluvial topset beds are generally thin (less than 3 m (10 ft) thick). Deltaic surfaces at and just south of Maromas are at 41 to 44 m (135 to 145 ft) and rise to 53 m (175 ft) at northernmost ice-marginal head; fluvial topset gradients on these deposits are steeper (about 3 m/km (10 ft/mi)) and topset beds are as much as 8 m (25 ft) thick. Deposition of greater thicknesses of topset beds in northern ice-marginal delta series of this unit is perhaps result of slower retreat in this area, where regional margin of ice sheet was mainly retreating down opposing northwest-facing slopes. Northernmost deposits, at Jobs Pond north of Connecticut River, are as much as 76 m (250 ft) thick and block former channel of Connecticut River; because these deposits were not trenched by later erosion, top of next-to-the-last delta preserves spillway channel at 47 m (155 ft) (same altitude as topset-foreset contact in last delta). This illustrates self-damming effect characteristic of SP depositional system; this type of spillway was not commonly preserved. (Middle Haddam, Deep River, Haddam)
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Old Lyme deposits - Ice-marginal deltaic deposits in upper Black Hall River valley with surfaces at 14 to 17 m (45 to 55 ft). Near-ice-marginal fluviodeltaic deposits in northern tributary valleys to Lieutenant River valley; fluvial deposits reach 21 m (70 ft) north of Rogers Lake and grade to deltaic surfaces south of lake at 14 to 17 m (45 to 55 ft). Deposits ponded behind heads of Westbrook-Old Saybrook-Old Lyme deposits (lcwoo) in Black Hall and Lieutenant River valleys. (Old Lyme)
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Eightmile River deposits - Successive ice-marginal deltas in Eightmile River valley with surfaces rising to the north from 17 m (55 ft) to 35 m (115 ft). Initially ponded behind Essex-Hamburg-Deep River deposits (lce) in Hamburg Cove; near-ice-marginal fluviodeltaic deposits north of State Route 82 have deltaic surfaces at 35 to 38 m (115 to 125 ft) near North Plain and fluvial surfaces rising to 53 m (175 ft) at northern end of unit. (Hamburg)
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Salmon River deposits - Predominantly near-ice-marginal fluviodeltaic deposits in lower Salmon River valley; one ice-margin position recorded at northeastern end of unit. Surface altitudes range from 29 m (95 ft) in the south to 59 m (195 ft) at northern end of unit. Because northeast-southwest trend of Salmon River valley was parallel to retreating ice margin, southern part at least probably was uncovered all at once instead of sequentially northward as were valleys that trended perpendicular to ice margin. Initial ponding of Salmon River valley was behind part of Tylerville-Portland deposits (lct), which provided a sediment dam; as ice margin retreated northwestward out of Salmon River valley, meltwater flowed down northwest tributary valleys of Pine, Elbow, and Wopowog Brooks. Fluvial sediments were deposited in steeper sections and these grade downstream to deltaic sediments in main valley; these deltas must have filled and blocked sections of valley, resulting in higher levels of ponding up Salmon River valley, as is indicated by 30-m (100-ft) rise in altitudes of deltaic surfaces. (Moodus, Deep River, Middle Haddam)
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Lower Blackledge River deposits - Series of ice-marginal deltaic deposits in main valley and near-ice-marginal fluviodeltaic deposits in which fluvial sediments in tributary valleys grade to deltas in main valley. Initial ponding was behind Salmon River deposits (sa) in Salmon River valley; levels of ponding increased up valley. Delta surfaces rise from 64 m (210 ft) at southern end of unit (ponded behind 67-m (220-ft) head of unit sa) to 99 m (325 ft) at northern end. (Marlborough, Moodus)
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Middle River deposits - Ice-marginal deltaic and fluviodeltaic deposits ponded behind blockage in bedrock narrows at Stafford Springs village. Deltaic surfaces are at 166 m (545 ft) at southern end of unit; fluvial feeder deposits, including eskers, reach 184 m (605 ft) in tributary valley of Patten Brook and at ice-marginal head just south of State Line Pond. Fluviodeltaic deposits extending into Massachusetts were ponded behind 184-m (605-ft) head. (Monson, Stafford Springs)
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Bigelow Brook deposits - Ice-marginal deltaic deposits at southern end of unit at 171 m (560 ft); blocked initially by uncorrelated ice-dammed pond deposits of unit ip. Terrace remnants at 188 m (615 ft) rise northward to ice-marginal position at 203 m (665 ft) in central part of unit; these deposits probably are mostly fluvial. Ice-marginal deltaic deposits with long feeder esker at northern end of unit extend across divide into Quinebaug River basin. (Southbridge, Westford, Eastford)
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Skungamaug River deposits - Ice-marginal fluviodeltaic deposits built as two successive sequences in southern half of valley graded to ponded level of about 148 m (485 ft); lake-bottom deposits at southern end with surface level of 137 to 140 m (450 to 460 ft); valley probably was dammed by meltwater deposits (u) in valley narrows at southern end. Northern half of unit was ponded behind moraine deposits (m) 2 km (1.6 mi) south of Tolland village. Deltaic surfaces are at 166 m (545 ft) in this section of valley; fluvial deposits reach 175 m (575 ft) at northern end. Sandy surfaces at 155 to 158 m (510 to 520 ft) just north of moraine probably are lake-bottom deposits. (Stafford Springs, South Coventry)
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Hop River deposits - Succession of at least six ice-marginal deltaic morphosequences along Hop River valley, although only two ice positions are clearly evident from surface morphology. Surface gradients rise from 90 m (295 ft) at eastern end of valley where deposits merge with those in Willimantic River valley, to 123 m (405 ft) to the west; this is an overall gradient of about 0.8 m/km (4 ft/mi), some of which is result of postglacial rebound. (Columbia, Marlborough, Rockville)
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Mount Hope River-Fenton River deposits - Successive ice-marginal fluviodeltaic deposits along two river valleys. Coarse gravelly terrace deposits and still coarser esker segments may be mostly fluvial with only minor deltaic sections; these deposits almost certainly are composite, but ice-contact heads are not clearly shown. At southern end of unit, where two valleys join in Mansfield Hollow Lake area, extensive deltaic deposit at 81 m (265 ft) was dammed behind northernmost ice-marginal head of Willimantic River-Upper Shetucket River deposits (wil). (Spring Hill)
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Natchaug River deposits - Successive ice-marginal fluviodeltaic deposits in Natchaug River valley; ice-margin positions not clearly shown. Deltaic surfaces rise from 111 m (365 ft) at southern end of unit to more than 183 m (600 ft) at northern end. This relatively steep gradient indicates much fluvial deposition. (Eastford, Hampton)
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Upper Willimantic River deposits - Series of ice-marginal fluviodeltaic deposits in section of upper Willimantic River valley that is narrow with a steep gradient. Ponding was initially behind head of Willimantic River deposits (wrl) at about 96 m (315 ft); deltaic surfaces are as high as 126 m (415 ft) in northern part of unit. (Stafford Springs, South Coventry)
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Willimantic River deposits - Successive ice-marginal deltaic and fluviodeltaic deposits in narrower section of Willimantic River valley behind head of Willimantic River-upper Shetucket River deposits (wil). Related to at least two ice-margin positions. Levels of ponding are slightly higher than in unit wil at 84 to 90 m (275 to 295 ft); fluvial feeder deposits reach 93 m (305 ft). (South Coventry, Columbia)
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Willimantic River-upper Shetucket River deposits - Predominantly successive ice-marginal deltaic and fluviodeltaic deposits in relatively wide, shallow-gradient section of Shetucket River valley. Deposits are related to at least 12 ice-margin positions. Initial ponding was behind lower Shetucket River deposits (str) and remnant ice blocks in narrows of Shetucket River at southern end of unit. Levels of successive ponding were at 72 to 78 m (235 to 255 ft); fluvial feeder deposits reach as high as 91 m (300 ft) in lower Natchaug River valley and Potash Brook valley. Ice-margin-parallel ridge at head of first ice-marginal delta in this series is at 84 m (275 ft), 15 m (50 ft) above the 72-m (235-ft) delta surface in front of it; this feature possibly may be a morainic ridge, but no gravel pits exist in which to observe internal structure. Relatively extensive meltwater-terrace unit inset into deltaic surfaces at Windham records 5- to 6-m (15- to 20-ft) drop in ponding level while meltwater still flowed down Potash Brook valley. (Willimantic, Scotland, Spring Hill)
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Upper Little River deposits - Ice-marginal deltaic and deltaic-fluvial deposits built at three southern ice positions; northernmost sequence is near-ice-marginal fluviodeltaic deposit. Ponding in southern part was at 108 to 111 m (355 to 365 ft), initially behind head of lower Little River deposits (lrl); fluvial deposits in third sequence reach as high as 142 m (465 ft); northern sequence ponded behind this head at 130 to 133 m (425 to 435 ft) has fluvial feeder deposits as high as 163 m (535 ft) at northern end. (Hampton, Scotland)
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Lower Little River deposits - Ice-marginal deltaic-fluvial morphosequences in southern half of Little River valley, related to at least three ice-margin positions. Initial ponding was at a level of 44 to 47 m (145 to 155 ft) behind lower Shetucket River deposits (str) at Versailles; surface gradients rise steeply northward to 111 m (365 ft) at northern end of unit. Levels of ponding increase about 15 m (50 ft) between sequences because of relatively thick fluvial aggradation at each head. (Scotland, Norwich)
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Merrick Brook-Beaver Brook-Ballymahack Brook deposits - Near-ice-marginal fluviodeltaic deposits in three valleys with long fluvial sections of very coarse gravel; fluvial deposits are as high as 137 m (450 ft) and grade southward with 7.8 to 9.7 m/km (40 to 50 ft/mi) gradients to deltaic deposits at 69 m (225 ft). Deltaic-fluvial deposits initially ponded against local divides at heads of Beaver and Merrick Brooks, near the long esker feeder; fluvial aggradation continued across those divides. (Spring Hill, Scotland, Willimantic, Hampton)
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Lower Shetucket River deposits - Successive ice-marginal deltaic deposits in main Shetucket River valley; ice-marginal and near-ice-marginal fluvial deposits in tributary valleys grade to deltas in Shetucket River and Beaver Brook valleys. Initial ponding was behind Yantic River deposits (yr) in Thames River valley; delta altitudes increase from 29 m (95 ft) at Taftville to 59 m (195 ft) at northern end of unit. (Norwich, Fitchville, Willimantic)
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Yantic River deposits - Ice-marginal deltas and fluviodeltaic deposits; near-ice-marginal fluvial deposits in tributary valleys are on grade to deltas in main Yantic River valley. Initial ponding was behind deltas of glacial Lake Uncasville (lu) and Trading Cove Brook (tc) in Thames River valley; delta altitudes rise from 29 m (95 ft) at confluence of Yantic and Thames Rivers to 53 m (175 ft) near village of Fitchville. (Norwich, Fitchville)
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Trading Cove Brook deposits - Near-ice-marginal fluviodeltaic and ice-marginal deltaic deposits; initially ponded behind deposits of glacial Lake Uncasville (lu) in Thames River valley at Trading Cove. Fluvial deposits in tributary valleys of Ford, Gardner, and Great Plain Brooks are as high as 35 m (115 ft) and grade to delta surfaces in lower Trading Cove Brook valley at 23 to 26 m (75 to 85 ft); northern part of unit consists of fluvial deposits as high as 72 m (235 ft) at northern end that slope steeply to delta surface at 32 m (105 ft) behind earlier ice-marginal deltas. (Fitchville, Norwich, Uncasville)
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Oxoboxo Brook deposits - Ice-marginal fluviodeltaic deposits in southeastern end of unit and successive ice-marginal deltas in northwestern part of Oxoboxo Brook valley. Proximal fluvial deposits at southern end of Oxoboxo Lake, probably built at Oxoboxo moraine (mom) position, are at 133 m (435 ft) and slope down-valley with a surface gradient greater than 9.7 m/km (50 ft/mi) to deltaic deposits at 84 m (275 ft) behind bedrock narrows at southern end of Wheeler Pond and head of glacial Lake Uncasville deposits (lu). Ice-marginal deltas north of Oxoboxo Lake were ponded behind the 133-m (435-ft) fluvial deposits and have surface altitudes of 127 to 130 m (415 to 425 ft). (Fitchville, Montville)
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East Lyme deposits - Ice-marginal and near-ice-marginal fluviodeltaic deposits in Fourmile River, Pataguanset River, and Stony Brook valleys; ponding in each valley was initially behind Niantic deposits (lcn). Delta surface altitudes increase from 20 m (65 ft) to 41 m (135 ft) in Fourmile River valley and from 14 m (45 ft) to 32 m (105 ft) in Pataguanset River valley and its tributaries, Latimer Brook and Lakes Pond Brook; youngest deposits head at Ledyard moraine (hlm). (Old Lyme, Niantic, Montville)
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Fivemile River deposits - Four successive ice-marginal deltas with surfaces at 123 to 126 m (405 to 415 ft) in valley south of Quaddick Reservoir; probably controlled by 123-m (405-ft) spillway on valley wall just downstream, at a time when narrow valley was blocked. Ice-marginal deltaic and fluviodeltaic deposits in northern half of unit have surface altitudes that rise at steeper gradient, from 133 m (435 ft) to 160 m (525 ft). Behind last ice-margin position in Connecticut, successive ice-marginal deltas through Lake Chaubunagungamaug basin and extending into Massachusetts are at 154 to 160 m (505 to 525 ft) and were graded to a spillway preserved at 145 m (475 ft) across earlier head. (Oxford, Thompson)
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West Thompson deposits - Remnants of successive ice-marginal fluviodeltaic deposits in Quinebaug River and French River valleys north of their confluence. Initial ponding was behind head of Putnam deposits (pt) in Quinebaug valley to the south. Southernmost deltaic surfaces are at 105 m (345 ft) and rise to 117 m (385 ft) in northern part of unit; fluvial feeder deposits are as high as 136 m (445 ft). (Webster, Putnam)
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East Woodstock deposits - Successive ice-marginal deltaic and fluviodeltaic deposits in Little River valley; southern sequences have surface altitudes at 105 to 111 m (345 to 365 ft), initially ponded behind high-level uncorrelated unit (u) in valley to the south before its collapse. Northernmost sequences are fluviodeltaic with fluvial feeders reaching 139 m (455 ft) and deltaic surfaces at 117 m (385 ft). (Putnam, Webster)
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Putnam deposits - Southern half of unit consists chiefly of successive ice-marginal deltas in Quinebaug River valley, dammed initially behind generally coarser Danielson deposits (da); delta surfaces rise from 78 m (255 ft) to 84 m (275 ft). Successive ice-marginal fluviodeltaic deposits in northern part of unit have delta surfaces that rise from 87 m (285 ft) to 107 m (350 ft) and fluvial feeder deposits that reach 123 m (405 ft). (Putnam, Danielson)
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Danielson deposits - Successive ice-marginal deltaic and fluviodeltaic deposits. Earlier deposits of this unit have deltaic surfaces at 69 to 75 m (225 to 245 ft); topset beds aggraded 3 to 6 m (10 to 20 ft) higher than those of glacial Lake Quinebaug (lqb) just to the south. These earlier deposits of unit da blocked the Quinebaug River valley, leading to construction of later deltas, mostly along Fivemile River, with surfaces at 81 to 84 m (265 to 275 ft). Fluvial terraces reach 87 m (285 ft) at Danielson and 91 m (300 ft) at northern end of unit. Southwest of Danielson, deposits cross till area and are locally graded to low spillways on till. (Danielson)
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Quinebaug River valley deposits - Ice-marginal deltas and fluviodeltaic deposits successively ponded in the Quinebaug River valley initially behind glacial Lake Quinebaug deposits (lqb) at slightly higher levels than projected glacial Lake Quinebaug water plane. Deltas have surface altitudes at 59 to 69 m (195 to 225 ft); several measured altitudes of delta topset-foreset contacts indicate levels of ponding 2 to 6 m (5 to 20 ft) higher than glacial Lake Quinebaug. (Plainfield, Danielson)
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Snake Meadow Brook deposits - Two ice-marginal fluviodeltaic deposits in Snake Meadow Brook valley, a south-flowing tributary to Moosup River. Initial ponding was behind deposits of unit ip, which blocked valley to as high as 102 m (335 ft) at Almyville. Delta surfaces at southern end of unit are at 96 m (315 ft); fluvial surfaces rise northward to 123 m (405 ft) at ice-margin position where State Route 52 crosses valley. Northern half of unit is ponded behind head of southern sequence; delta surfaces are at 120 m (395 ft) (topset-foreset contact at about 116 m (380 ft)); fluvial surfaces rise northward to 133 m (435 ft) at ice-margin position. (East Killingly, Oneco)
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Mount Misery Brook deposits - Series of four ice-marginal deltaic deposits along Mount Misery Brook between Pachaug River and Lowden Brook; these are succeeded by near-ice-marginal fluviodeltaic sequence north of Lowden Brook. Delta surfaces rise from 78 m (255 ft) to 93 m (305 ft) between Voluntown and Lowden Brook; fluvial sediments in northern part of unit reach 114 m (375 ft). Initially ponded against deposits of adjacent glacial Lake Voluntown (lvo); subsequent ponding behind successive heads were filled with lake-bottom sediments, most of which are now covered by large swamps in valley. (Oneco, Voluntown)
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Indiantown Brook deposits - Predominantly successive ice-marginal deltaic deposits with minor fluvial feeders. Deposits occur in long divide area north of Indiantown Brook, occupied by large kettle-hole ponds. Deltaic surfaces rise from 38 m (125 ft) northward to 50 m (165 ft). Initial ponding was in basin behind bedrock narrows on Shewville Brook, which may have been filled with till or dead ice to an altitude 3 to 5 m (10 to 15 ft) higher than today. Very coarse grained fluvial deposits at northeasternmost ice-margin position reach 59 m (195 ft). (Jewett City, Old Mystic)
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Cedar Swamp-Whitford Brook deposits - Southern part of unit consists of ice-marginal fluvial sediments in Whitford Brook valley and near-ice-marginal fluvial sediments in Williams Brook valley that grade to extensive deltaic deposits to the south. Deltaic deposits have surface altitudes at 44 to 50 m (145 to 165 ft) and are underlain by as much as 24 m (80 ft) of lake-bottom sediment. Fluvial deposits reach 47 m (155 ft) at ice-margin position. Northern part of unit, between Lantern Hill and Cedar Swamp, consists of three successive ice-marginal deltas, including network of esker feeders; last delta heads at segment of Ledyard moraine (hlm), which forms southern border of Cedar Swamp. Initial ponding in this unit was behind head of Mystic-Stonington deposits (lcms) related to glacial Lake Connecticut and a segment of the Old Saybrook moraine (owm). (Old Mystic)
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Shunock River deposits - Successive ice-marginal deltaic and fluviodeltaic deposits in Shunock River valley. Ponding was initially behind head of lower Pawcatuck River deposits (pl) to the south. The first two sequences are ice-marginal deltas with surface altitudes of 20 m (65 ft); north of these, an ice-marginal fluviodeltaic sequence heads at Old Saybrook moraine (owm) position in valley where coarse gravel fluvial sediments have surface altitudes at 41 m (135 ft) and grade southward to deltaic deposits at 26 m (85 ft). North of this ice position, delta surfaces are higher at 44 m (145 ft) to 47 m (155 ft); northernmost deposit in unit is long, near-ice-marginal fluviodeltaic morphosequence heading just downstream from Ledyard moraine (hlm) position with fluvial surfaces as high as 69 m (225 ft). (Old Mystic, Ashaway)
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Upper Pawcatuck River deposits - Successive ice-marginal deltaic and fluviodeltaic deposits in Pawcatuck River valley and its northeast tributaries. Ponding was initially behind part of Shunock River deposits (sn) at Shunock River junction with Pawcatuck River. Earlier sequences are ice-marginal deltas with surface altitudes of 20 to 26 m (65 to 85 ft). Ice-marginal fluviodeltaic deposit heads at segment of Old Saybrook moraine (owm) at southern end of Bell Cedar Swamp; here, fluvial deposits at 38 m (125 ft) slope steeply southward from moraine to delta at 26 m (85 ft). In Ashaway River valley east of there, ice-marginal delta heads at moraine position. North of moraine position in Spaulding Pond, Green Fall River, and Ashaway River valleys, near-ice-marginal fluviodeltaic deposits occur; fluvial sediments as high as 66 m (215 ft) slope steeply southward to deltaic sediments at 32 m (105 ft) ponded behind moraine positions. (Ashaway)
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Anguilla Brook deposits - Inferred to be series of dominantly deltaic deposits, initially blocked at narrow bend in valley. Overall gradient of about 3.9 m/km (20 ft/mi) is too steep for simple ponding of one segment behind another and indicates presence of considerable fluvial material. (Old Mystic, Ashaway, Watch Hill)
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Lower Pawcatuck River deposits - At least four successive ice-marginal deltaic and fluviodeltaic deposits in lower Pawcatuck River valley behind Charlestown (hcm) and smaller Avondale (cm) moraines. Overall surface gradient slopes from 41 m (135 ft) southward to 5 m (15 ft). (Ashaway, Watch Hill)
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Small, uncorrelated proximal fluvial deposits
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Norwalk River-Fivemile River deposits - Near-ice-marginal fluvial deposits in steeper sections of upper Fivemile River valley and Norwalk River valley. Surface profiles rise from about 14 m (45 ft) in both valleys just north of ice-marginal head of Stamford-Norwalk-Westport deposits (lcsnw) northward to 61 m (200 ft) in Fivemile River valley and 44 m (145 ft) in Norwalk River valley. Composed chiefly of thin (less than 10 m (30 ft)), gravelly, fluvial sediments. Small pockets of ponded sediments may be present locally at depth. (Norwalk North, Norwalk South)
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Byram River deposits - Near-ice-marginal fluvial deposits in narrow and relatively steep Byram River valley. Deposits are near sea level at southern end of valley (in New York) and rise to 55 m (180 ft) to the north. Probably constructed as several morphosequences. Small pockets of ponded sediment may be present locally at depth. (Glenville, Mamaroneck)
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West Branch Naugatuck River deposits - Ice-marginal and near-ice-marginal fluvial deposits in steep upper reaches of Naugatuck River and its west branch. Northernmost fluvial sequence reaches 30 m (100 ft) and slopes on a steep gradient; southern sequence in city of Torrington slopes from 198 m (650 ft) at northern end to 165 m (540 ft) at southern end, a gradient of about 9.7 m/km (50 ft/mi). (Norfolk, West Torrington, Torrington)
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Meriden deposits - Fluvial deposits in the Sodom Brook valley grade from boulder-cobble gravel with surface altitude at 59 m (195 ft) at ice-contact head, southward through finer gravel and sand, to sand and some silt underlying Quinnipiac Valley terrace deposits (qt) at South Meriden. Base level for meltwater streams that built this unit may have been glacial Lake Quinnipiac. Character of deposits in Harbor Brook valley in eastern part of unit is uncertain; several well logs from center of Meriden mention sand and silt in subsurface, indicating possible ponding. (Meriden)
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Woods Stream-Wrights Brook deposits - Ice-marginal fluvial deposits in relatively steep, south-draining tributary valleys north of Scantic River; deposited from both sides of an interlobate angle between Connecticut Valley ice lobe and eastern upland ice margin. Heads of deposits in several places lie on drainage divides; ice margin to the north was requisite to deposition in those places. (Broad Brook, Ellington, Springfield South, Hampden)
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Upper Blackledge River fluvial deposits - Series of three near-ice-marginal fluvial deposits in upper Blackledge River valley; steep surface gradients of more than 5.8 m/km (30 ft/mi). (Marlborough, Rockville)
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Branford River fluvial deposits - Series of short, ice-marginal fluvial deposits in Branford River, Pisgah Brook, and Stony Creek. (Branford)
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Sherman Brook-Bartlett Brook-Pease Brook deposits - Ice-marginal and near-ice-marginal fluvial morphosequences in steep tributary valleys to Yantic River; surface gradients are 7.8 to 9.7 m/km (40 to 50 ft/mi) and deposits are coarse gravel facies in most proximal parts. (Colchester, Fitchville, Willimantic, Columbia)
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Jordan Brook-Hunts Brook-Green Marsh Brook deposits - Ice-marginal fluvial deposits in steep sections of three valleys; shingled against proximal fluvial heads of Jordan Cove-lower Thames River deposits (lcjl) in lower part of each valley. Surface gradients in each sequence are 7.8 to 9.7 m/km (40 to 50 ft/mi); first sequence in Hunts Brook valley heads at Ledyard moraine (hlm); sequence in Jordan Brook valley is near-ice-marginal, built from Ledyard moraine position on upland about 0.4 km (0.25 mi) to the north of unit. (Montville, Uncasville, New London, Niantic)
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Groton deposits - Ice-marginal fluvial deposits in steep upper sections of tributary valleys to Poquonock River; head of outwash in Hempstead Brook valley lies on northern divide at 35 m (115 ft) and slopes southward at about 7.8 m/km (40 ft/mi); shingled against ice-marginal fluvial head of Poquonock River deposits (lcp). Deposits in Rosemond Lake valley head at Ledyard moraine (hlm) and also at northern divide at 59 m (195 ft), and slope southward with a gradient of about 4.8 m/km (25 ft/mi) to 32 m (105 ft), shingled against the 41-m (135-ft) head of unit lcp in that valley. (Uncasville, New London)
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Kitt Brook deposits - Ice-marginal and near-ice-marginal fluvial deposits in Kitt Brook valley. Probably at least three sequences, subtly marked by breaks in surface gradient which, over whole unit, slopes southward from 96 m (315 ft) to 78 m (255 ft). (Scotland, Plainfield)
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Carson Brook deposits - Ice-marginal fluvial deposit in Carson Brook valley; unit is more extensive in Rhode Island. Probably several successive sequences occur within unit. Overall surface gradient slopes southward from 128 m (420 ft) to 102 m (335 ft). Sediment was deposited around numerous large ice blocks. (Oneco)
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Avondale outwash deposits - Small area of ice-marginal fluvial sediments built from Avondale moraine (cm) ice position; unit is more extensive farther east in Rhode Island. (Watch Hill)
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Charlestown outwash deposits - Very coarse fluvial gravel deposits in outwash fans directly in front of Charlestown moraine (hcm); deposits extend below present sea level. Unit shown on map is westernmost end of much more extensive deposits that occur farther east in Rhode Island. (Watch Hill)
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Fishers Island outwash deposits - Coarse fluvial gravel deposits in outwash fan in front of western end of Fishers Island moraine (hcm). May be more extensive below modern sea level but have not been mapped. (New London)
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Uncorrelated meltwater terrace deposits
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Blackberry River terrace deposits - Distal-meltwater fluvial-terrace deposits, generally less than 6 m (20 ft) thick, overlying and inset into lake-bottom deposits of glacial Lake Norfolk. Terraces are only about 3 m (10 ft) above present stream levels. Deposited as meltwater continued to flow down Whiting River valley after draining of glacial Lake Norfolk. Part of unit that appears to come from upper Blackberry River is probably of nonmeltwater origin. (Ashley Falls)
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Farmington Valley meltwater terrace deposits - Fluvial deposits at 66 to 56 m (215 to 185 ft) in north-flowing section of Farmington River, and at 62 to 59 m (205 to 195 ft) in lower Salmon Brook valley north of Tariffville. Fluvial sand and gravel generally less than 8 m (25 ft) thick overlies deltaic and lake-bottom sediments of glacial Lakes Farmington (lf) and Tariffville (lt) and Simsbury lacustrine deposits (sl). Terraces began to form after Tariffville Gap was opened and meltwater drainage in the Farmington River valley shifted from the southward flow that constructed Quinnipiac Valley terrace deposits (qt) to northward flow through the gap. As lake levels in the upper Connecticut River basin lowered to higher New Britain spillway levels, distal meltwater initially forming fvt terrace discharged through Tariffville Gap and built southwestern part of the Windsor deltaic deposits (lhhw) in glacial Lake Hitchcock. As lake levels continued to drop, the Bradley International Airport delta (lhsb) was deposited into lake by waters constructing the fvt terrace. Meltwater terrace remnants (fd) farther upstream along Farmington River valley in uplands may be correlative with fvt terrace. (New Britain, Avon, Tariffville)
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Quinnipiac River valley terrace deposits - Fluvial deposits inset into earlier ice-marginal deposits of glacial Lakes Farmington and Southington. Head of deposit is at Farmington where surface is at 64 m (210 ft) and extends southward to North Haven where surface is at 11 m (35 ft). In lower Quinnipiac River valley (south of the Quinnipiac Gorge), these sediments overlie lake-bottom deposits of glacial Lake Quinnipiac. In upper Quinnipiac River valley, terrace sediments are inset against and overlie deltaic and lake-bottom sediments of glacial Lakes Farmington and Southington. Sediments contain high percentage of crystalline clasts because they were deposited predominantly by meltwater coming out of western highlands down Pequabuck and Farmington River drainages; this is in contrast to high percentage of Triassic and Jurassic sedimentary clasts in older ice-marginal deposits in Quinnipiac River valley. (Wallingford, Meriden, Southington, New Britain)
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Hampden-Somers meltwater terrace deposits - Connecticut part of unit consists of distal fluvial terrace deposits deposited by meltwater that eroded and redistributed parts of glacial Lake Somers deposits (lso) and contributed sediment to northern parts of Scantic River delta deposits (lhhs) of glacial Lake Hitchcock. Ice-marginal head is several miles to the north in Massachusetts where it consists of ice-proximal fluvial deposits. (Hampden, Ellington)
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Hockanum River valley meltwater terrace deposits - Distal fluvial terrace deposits at 69 m (225 ft), near Vernon-Ellington town line, grade southwest to 47-m (155-ft) altitude of Hockanum River delta deposit (lmh), which was fed by meltwater that built unit ht. Meltwater spilled from glacial Lake Ellington to the north and eroded and redistributed eastern margin delta deposits (lme) as it built unit ht terrace. (Rockville, Manchester)
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Farmington River terrace deposits - Thin fluvial sediments incised into and overlying Bradley International Airport delta deposits (lhsb); deposited by meteoric water of postglacial Farmington River before drainage of glacial Lake Hitchcock. This fluvial terrace is on grade with post-stable-level delta of glacial Lake Hitchcock (lhf). (Windsor Locks)
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Thin till deposits - Mapped in areas where till generally is less than 4 to 5 m (12 to 15 ft) thick. Discontinuous on slopes or in areas of moderate local relief where bedrock outcrops are numerous and where bedrock surface topography controls local relief of land surface. Predominantly upper till that is loose to moderately compact, generally sandy, commonly stony. Both lodgement and ablation facies present in places
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Thick till deposits - Mapped in areas where till generally is more than 4 to 5 m (12 to 15 ft) thick, in glacially smoothed landforms that mask bedrock surface topography. In places, particularly in drumlins, till thickness exceeds 30 m (100 ft); maximum reported thickness is about 61 m (200 ft). Lower till constitutes bulk of till deposits in these areas, although upper till generally is present at surface. Lower till is moderately to very compact, and is commonly finer grained and less stony than upper till. Oxidized zone (lower part of soil profile developed during period of interglacial weathering) generally is present in upper part of lower till section; this zone commonly shows closely spaced joints stained with iron and manganese oxides
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End moraine deposits, uncorrelated - Morainal deposits in short, discontinuous segments. Includes narrow morainal ridge at Windsorville village and other small patches of morainal deposits
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Harbor Hill-Fishers Island-Charlestown moraine deposits - Thick and continuous morainal deposits on Long Island, N.Y. (from Fuller, 1914), Fishers Island, N.Y. (from Goldsmith, 1962; and Upson, 1971), and Rhode Island (from Schafer, 1965). Also includes submerged morainal deposits mapped from seismic lines (see description of unit osm) in lower lying areas east and west of Fishers Island. This massive morainal deposit accumulated along ice margin during major stand of late Wisconsinan ice sheet approximately 20 km (12 mi) north of terminal moraine. Although unit occurs entirely outside of Connecticut, it is shown on map because these deposits provided dam for glacial Lake Connecticut; deep notch across submerged part of moraine at The Race (just west of Fishers Island) was glacial-lake spillway
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Clumps-Avondale moraine deposits - Clumps moraine segment is chain of small bouldery islands and shoals extending about 12 km (7 mi) from island of South Dumpling, N.Y., to Napatree Point, R.I. Submerged deposits exhibit internal reflection characteristics typical of bouldery till. Submerged ice-marginal lacustrine fan deposits (lcf) in places adjacent to morainal position. Avondale moraine segment is in Rhode Island and consists of narrow ridges of ablation till 6 to 15 m (20 to 49 ft) thick at head of Avondale outwash deposits (ao). Clumps-Avondale moraine is parallel to and about 1 km (0.6 mi) north of Fishers Island-Charlestown moraine. (New London, Mystic, Watch Hill)
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Mystic moraine deposits - Double linear belt of discontinuous, aligned ridges, many of which are extremely bouldery. Moraine extends 20 km (12 mi) from Pine Island south of Groton to Pawcatuck; line of submerged ice-marginal lacustrine fans (lcf) offshore of Groton occurs adjacent to and along trend of Mystic moraine. (New London, Mystic, Watch Hill)
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Old Saybrook-Wolf Rocks moraine deposits - Extends from shoreline at Cornfield Point in Old Saybrook along N. 70° E. trend for about 53 km (33 mi) to Rhode Island border in North Stonington; a few moraine segments were mapped in Rhode Island along same trend to Wolf Rocks in North Kingston. Double linear belt of aligned segments, including many long boulder belts. Individual segments in well-developed double line zone between mouth of Connecticut River and New London are up to 3 km (1.8 mi) in length; these segments mostly stand at heads of ice-marginal deltaic deposits built into glacial Lake Connecticut. Offshore between Old Saybrook and Lordship, submerged extensions become co-extensive with lobate ice-marginal lacustrine fan deposits (lcf). (Essex, Old Lyme, Niantic, New London, Uncasville, Old Mystic, Ashaway)
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Hammonasset-Ledyard moraine deposits - Double linear belt of aligned segments. Hammonasset belt includes paired, parallel segments composed of linear bodies of till up to 2 km (1.2 mi) in length. Extends 10 km (6 mi) from shoreline areas at Hammonasset Point to village of Westbrook; many segments are at heads of ice-marginal deltaic deposits built into glacial Lake Connecticut. Extends from Hammonasset Point westward beneath Long Island Sound as linear belt of small shoals and islands formed by crest of submerged morainal deposits. East of Connecticut River, extends 36 km (22 mi) from east of Rogers Lake in Old Lyme through East Lyme, Waterford, and Ledyard to Ashwillet Brook in North Stonington; through this section, composed of aligned segments individually up to 3 km (1.8 mi) in length. In valleys, segments are bouldery till bodies at heads of deltaic morphosequences; across upland areas, segments are linear concentrations of large boulders. Probably correlates with several discontinuous morainal deposits in western Rhode Island (Queens River moraine). (Clinton, Essex, Old Lyme, Hamburg, Montville, Uncasville, Old Mystic)
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Madison-Oxoboxo moraine deposits - Madison belt contains six segments of ridges and mounds of bouldery till, individually less than 1 km (0.6 mi) in length with paired, parallel segments at east end. Extends 8 km (5 mi) from Hogshead Point in Guilford eastward to Hammonasset River; offshore to the west, includes three shoals and submerged deposits. Oxoboxo belt east of Connecticut River contains eight short and discontinuous linear patches of large boulders and mounds of hummocky till. Extends 10 km (6 mi) from Barnes Reservoir to Stony Brook Reservoir. (Guilford, Clinton, Essex, Montville)
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Captain Islands-Norwalk Islands moraine deposits - Two linear belts of aligned emergent islands and shoals, and other submerged deposits. Captain Islands belt includes three islands and peninsula at Greenwich Point in exposed segments 0.08 to 1.20 km (0.05 to 0.75 mi) in length. Extends 10 km (6 mi) from Mansuring Island, N.Y., to Greenwich Point. Norwalk Islands belt contains 13 small islands and numerous shoals composed of nonsorted sediments and subordinate stratified materials exposed in island sea cliffs. Submerged morainal ridge is 10 km (6 mi) long, as much as 2.25 km (1.4 mi) wide, and as much as 17 m (56 ft) high above sea floor. Appears to correlate with Lordship proximal fan deposits (lcf) and inter-lobate ice-marginal delta position at Lordship (lcl) and continues the submerged proximal fan deposits to Old Saybrook-Wolf Rocks moraine deposits (owm) onshore at Cornfield Point. (Mamaroneck, Bayville, Stamford, Norwalk North, Sherwood Point)
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Area of glaciofluvial deposits grading to glacial lake - shown within glacial lake map units, indicated by f- prefix.
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Area of lake-bottom sediments - shown within glacial lake map units, indicated by l- prefix.
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Quaternary Geology - This attribute provides the full text name for the values stored in the QUPOLY_COD field. Quaternary Geology is the English language equivalent of (decodes) the QUPOLY_COD field. For example, QUPOLY_COD and QUATGEOL attribute values for the same polygon feature are st and Stream-terrace deposits, respectively.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
ArcView Software Legend - A text field used to classify and symbolize Quaternary Geology polygon features into broad categories, more suitable for use with ArcView software. The AV_LEGEND attribute condenses the 285 Quaternary map units (QUPOLY_COD values) into 26 broad categories of deposits. Glacial meltwater deposits are gropued together by facies and depositional system, for example Lake Bottom Deposits of Sediment Dammed Lakes.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
This category includes the following Quaternary Geology map unit: Artificial Fill (af).
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This category includes the following Quaternary Geology map unit: Coastal Beach And Dune Deposits (b).
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This category includes the following Quaternary Geology map units: Blackberry River Terrace Deposits (bb), Farmington River Terrace Deposits (fvt), Farmington River Terrace Deposits (ft), Hampden-Somers Terrace Deposits (hm), Hockanum River Terrace Deposits (ht), Quinnipiac River Terrace Deposits (qt), and Uncorrelated Deposits of Distal Meltwater Streams (fd).
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This category includes the following Quaternary Geology map units: Glacial Lake Bristol Deposits (lbr), Glacial Lake Coginchaug Durham Stage Deposits (lcgd), Glacial Lake Coginchaug Middletown Stage Deposits (lcgm), Glacial Lake Colchester Deposits (lc), Glacial Lake Cornwall Deposits (lcw), Glacial Lake Danbury Pond Brook Stage Deposits (ldp), Glacial Lake Danbury Pumpkin Hill Stage Deposits (ldh), Glacial Lake Danbury Saugatuck Divide Stage Deposits (lds), Glacial Lake Essex Deposits (lex), Glacial Lake Hollenbeck Deposits (lh), Glacial Lake Manchester Deposits (lma), Glacial Lake Nepaug Deposits (lnp), Glacial Lake Norfolk Deposits (ln), Glacial Lake Oneco Deposits (lon), Glacial Lake Pachaug Deposits (lp), Glacial Lake Pootatuck Deposits (lpt), Glacial Lake Roaring Brook Deposits (lrb), Glacial Lake Salmon Brook Deposits (lsb), Glacial Lake Voluntown Deposits (lvo), and Glacial Lake Winsted Deposits (lw).
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This category includes the following Quaternary Geology map units: Bantam River Deposits (ba), Bay Mountain Deposits (bm), Beaver Brook Deposits (bv), Bethany Deposits (be), Broad Brook Deposits (bd), Burlington Deposits (bt), Cedar Swamp Deposits (cs), Cobble Brook Deposits (co), Coginchaug Divide Deposits (cg), Colchester Deposits (cl), Conat Brook Deposits (cr), East Mountain Reservoir Deposits (emt), East Putnam-Glocester Deposits (epg), Fitchville Deposits (fv), Gardner Lake Deposits (gl), Hanging Hills Deposits (hh), Judd Brook-Gillette Brook Deposits (jg), Ledyard Deposits (led), Malory Brook Deposits (ml), Mashapaug Pond Deposits (mp), Mashentuck Mountain Deposits (ms), Mill Brook Deposits (mb), Moodus-pine Brook Deposits (mop), Mount Sanford Ridge Deposits (msr), North Thompson Deposits (nth), Onion Mountain Deposits (om), Pootatuck River Divide Deposits (pd), Quinnipiac River-Mill River Deposits (qm), Shenipsit Deposits (sh), Somers Deposits (so), Southbury Deposits (su), Still River Divided Deposits (sd), Tolles-Terryville Deposits (to), Uncorrelated Deposits of Ice Dammed Ponds (ip), Upper Connecticut Divide Deposits (cd), Vernon-Lydallville Deposits (vl), Wapping Deposits (wa), Wauregan Deposits (wr), West Branch Salmon Brook Deposits (wbs), West Haddam Deposits (whd), Whigville Deposits (wv), White Brook Deposits (wb), and Woodbury Deposits (wd).
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This category includes the following Quaternary Geology map units: Branford Deposits (bf), Byram River Deposits (by), Carson Brook Deposits (ca), Groton Deposits (gr), Jordan-Hunts-Green Marsh Brook Deposits (jhg), Kitt Brook Deposits (kb), Mad River Deposits (mdr), Meriden Deposits (me), Norwalk-Fivemile River Deposits (nf), Sherman-Bartlett-Pease Brook Deposits (sbp), Snake Meadow Brook Deposits (smb), Uncorrelated Deposits Of Proximal Meltwater Streams (fp), Upper Blackledge River Deposits (bu), West Branch Naugatuck River Deposits (nwb), and Woods Stream-Wrights Brook Deposits (ww).
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This category includes the following Quaternary Geology map units: Glacial Lake Bantam Deposits (lb), Glacial Lake Connecticut Devon and Milford Deposits (lcdm), Glacial Lake Connecticut East Haven Deposits (lcenh), Glacial Lake Connecticut East River-West River Deposits (lcew), Glacial Lake Connecticut Hammonasset River-Menunketsuck River Deposits (lchm), Glacial Lake Connecticut Jordan Cove-Lower Thames River Deposits (lcjl), Glacial Lake Connecticut Lordship Deposits (lcl), Glacial Lake Connecticut Mystic-Stonington Deposits (lcms), Glacial Lake Connecticut New Haven Deposits (lcnh), Glacial Lake Connecticut Niantic Deposits (lcn), Glacial Lake Connecticut Poquonock River Deposits (lcp), Glacial Lake Connecticut Stamford-Norwalk-Westport Deposits (lcsnw), Glacial Lake Connecticut Stratford-Southport Deposits (lcss), Glacial Lake Connecticut Westbrook-Old Saybrook-Old Lyme Deposits (lcwoo), Glacial Lake Ellington Deposits (le), Glacial Lake Farmington Deposits (lf), Glacial Lake Great Falls Deposits (lg), Glacial Lake Hitchcock Bradley Airport Delta Deposits (lhsb), Glacial Lake Hitchcock East Windsor Fluviodeltaic Deposits (lhhe), Glacial Lake Hitchcock Enfield Deltaic Deposits (lhhrn), Glacial Lake Hitchcock High-level Hockanum Delta Deposits (lhhh), Glacial Lake Hitchcock High-level Scantic River Deltaic Deposits (lhhs), Glacial Lake Hitchcock Ice-hole Deposits (lhhi), Glacial Lake Hitchcock Lake Hitchcock Beach Deposits (lhbe), Glacial Lake Hitchcock Post-stable-level Farmington River Delta Deposits (lhf), Glacial Lake Hitchcock Rattlesnake Brook Deltaic Deposits (lhhr), Glacial Lake Hitchcock Shea Corner Deltaic Deposits (lhhsc), Glacial Lake Hitchcock Spit Deposits (lhhp), Glacial Lake Hitchcock Stable-level Hockanum River Delta Deposits (lhsh), Glacial Lake Hitchcock Stable-level Scantic River and Broad Brook Delta Deposits (lhss), Glacial Lake Hitchcock Windsor Deltaic Deposits (lhhw), Glacial Lake Kenosia Deposits (lk), Glacial Lake Limerock Deposits (ll), Glacial Lake Middletown Cromwell Deltaic Deposits (lmc), Glacial Lake Middletown Eastern Margin Deltaic Deposits (lme), Glacial Lake Middletown Great Pond Delta Deposits (lmg), Glacial Lake Middletown Hockanum River Delta Deposits (lmh), Glacial Lake Middletown Newington Deltaic Deposits (lmn), Glacial Lake Middletown Portland Deltaic Deposits (lmp), Glacial Lake Middletown Western Margin Deltaic Deposits (lmw), Glacial Lake Middletown Windsorville Deltaic Deposits (lmwv), Glacial Lake Pomperaug Deposits (lpg), Glacial Lake Quinebaug Deposits (lqb), Glacial Lake Quinnipiac Deposits (lq), Glacial Lake Somers Deposits (lso), Glacial Lake Southington Deposits (ls), Glacial Lake Tariffville Deposits (lt), and Glacial Lake Uncasville Deposits (lu).
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This category includes the following Quaternary Geology map units: Anguilla Brook Deposits (an), Barkhamsted Reservoir Deposits (bk), Bigelow Brook Deposits (bg), Cedar Swamp-Whitford Brook Deposits (cw), Danielson Deposits (da), Dividend Brook Deposits (db), East Lyme Deposits (el), East Woodstock Deposits (ew), Eightmile Brook Deposits (eb), Eightmile River Deposits (eg), Fivemile River Deposits (fr), Hammonasset River Deposits (hr), Hop River Deposits (hp), Housatonic River Deposits, New Milford-West Cornwall (hrn), Housatonic River Deposits, Stratford-Shepaug (hrs), Indiantown Brook Deposits (ib), Lower Blackledge River Deposits (bl), Lower Connecticut River Deposits, Chester-Hadlyme (lcc), Lower Connecticut River Deposits, Essex-Hamburg-Deep River (lce), Lower Connecticut River Deposits, Tylerville-Portland (lct), Lower Little River Deposits (lrl), Lower Pawcatuck River Deposits (pl), Lower Shetucket River Deposits (str), Lower Willimantic River Deposits (wrl), Merrick-Beaver-Ballymahack Brook Deposits (mbb), Middle River Deposits (mr), Mount Hope-Fenton River Deposits (mf), Mount Misery Brook Deposits (mm), Natchaug River Deposits (na), Naugatuck River Deposits, Derby-Beacon Falls (nrd), Naugatuck River Deposits, Naugatuck-Reynolds Bridge (nrn), Naugatuck River Deposits, Thomaston-Litchfield (nrt), Old Lyme Deposits (ol), Oxoboxo Brook Deposits (ox), Pequonnock-Farmill River Deposits (pf), Putnam Deposits (pt), Quinebaug Valley Deposits (qb), Quonnipaug Lake-East and West River Deposits (qn), Rippowam-Noroton River Deposits (rn), Salisbury Deposits (sy), Salmon River Deposits (sa), Saugatuck-Aspetuck River Deposits (sas), Shepaug River Deposits (sr), Shunock River Deposits (sn), Simsbury Lacustrine Deposits (sl), Skungamaug River Deposits (sk), Southington-Bristol Deposits (sb), Southwick-Suffield Deposits (ss), Trading Cove Brook Deposits (tc), Uncorrelated Deposits of Sediment Dammed Ponds (sp), Unionville Deposits (un), Upper Branford River Deposits (bfr), Upper Farm River-Muddy River Deposits (fm), Upper Farmington River Deposits (fu), Upper Hammonasset River Deposits (hu), Upper Little River Deposits (lru), Upper Mill River Deposits (mu), Upper Pawcatuck River Deposits (pu), Upper Wepawaug River Deposits (wu), Upper Willimantic River Deposits (wru), Uppper Norwalk River Deposits (nu), West Simsbury Deposits (ws), West Thompson Deposits (wt), Westbrook-Old Saybrook Deposits (wo), Willimantic Valley Deposits (wil), and Yantic River Deposits (yr).
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This category includes the following Quaternary Geology map units: Captain Islands-Norwalk Islands Moraine Deposits (cnm), Hammonasset-Ledyard Moraine Deposits (hlm), Madison-Oxoboxo Moraine Deposits (mom), Moraine Deposits, Uncorrelated (m), and Old Saybrook-Wolf Rocks Moraine Deposits (owm).
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This category includes the following Quaternary Geology map unit: Flood-plain Alluvium (a).
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This category includes the following Quaternary Geology map units: Glaciofluvial Facies of Glacial Lake Bristol Deposits (f-lbr), Glaciofluvial Facies of Glacial Lake Coginchaug Durham Stage Deposits (f-lcgd), Glaciofluvial Facies of Glacial Lake Danbury Saugatuck Divide Stage Deposits (f-lds), Glaciofluvial Facies of Glacial Lake Essex Deposits (f-lex), Glaciofluvial Facies of Glacial Lake Oneco Deposits (f-lon), Glaciofluvial Facies of Glacial Lake Pachaug Deposits (f-lp), Glaciofluvial Facies of Glacial Lake Pootatuck Deposits (f-lpt), Glaciofluvial Facies of Glacial Lake Roaring Brook Deposits (f-lrb), Glaciofluvial Facies of Glacial Lake Salmon Brook Deposits (f-lsb), and Glaciofluvial Facies of Glacial Lake Winsted Deposits (f-lw).
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This category includes the following Quaternary Geology map units: Glaciofluvial Facies of Glacial Lake Connecticut Devon and Milford Deposits (f-lcdm), Glaciofluvial Facies of Glacial Lake Connecticut East Haven Deposits (f-lcen), Glaciofluvial Facies of Glacial Lake Connecticut East River-West River Deposits (f-lcew), Glaciofluvial Facies of Glacial Lake Connecticut Hammonasset River-Menunketsuck River Deposits (f-lchm), Glaciofluvial Facies of Glacial Lake Connecticut Jordan Cove-Lower Thames River Deposits (f-lcjl), Glaciofluvial Facies of Glacial Lake Connecticut Mystic-Stonington Deposits (f-lcms), Glaciofluvial Facies of Glacial Lake Connecticut New Haven Deposits (f-lcnh), Glaciofluvial Facies of Glacial Lake Connecticut Niantic Deposits (f-lcn), Glaciofluvial Facies of Glacial Lake Connecticut Poquonock River Deposits (f-lcp), Glaciofluvial Facies of Glacial Lake Connecticut Stamford-Norwalk-Westport Deposits (f-lcsn), Glaciofluvial Facies of Glacial Lake Connecticut Stratford-Southport Deposits (f-lcss), Glaciofluvial Facies of Glacial Lake Connecticut Westbrook-Old Saybrook-Old Lyme Deposits (f-lcwo), Glaciofluvial Facies of Glacial Lake Farmington Deposits (f-lf), Glaciofluvial Facies of Glacial Lake Hitchcock East Windsor Fluviodeltaic Deposits (f-lhhe), Glaciofluvial Facies of Glacial Lake Middletown Eastern Margin Deltaic Deposits (f-lme), Glaciofluvial Facies of Glacial Lake Middletown Western Margin Deltaic Deposits (f-lmw), Glaciofluvial Facies of Glacial Lake Middletown Windsorville Deltaic Deposits (f-lmwv), Glaciofluvial Facies of Glacial Lake Pomperaug Deposits (f-lpg), Glaciofluvial Facies of Glacial Lake Quinebaug Deposits (f-lqb), Glaciofluvial Facies of Glacial Lake Somers Deposits (f-lso), Glaciofluvial Facies of Glacial Lake Southington Deposits (f-ls), Glaciofluvial Facies of Glacial Lake Tariffville Deposits (f-lt), and Glaciofluvial Facies of Glacial Lake Uncasville Deposits (f-lu).
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This category includes the following Quaternary Geology map unit: Inland Dune Deposits (d).
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This category includes the following Quaternary Geology map units: Lake-bottom Facies of Glacial Lake Bristol Deposits (l-lbr), Lake-bottom Facies of Glacial Lake Coginchaug Durham Stage Deposits (l-lcgd), Lake-bottom Facies of Glacial Lake Coginchaug Middletown Stage Deposits (l-lcgm), Lake-bottom Facies of Glacial Lake Colchester Deposits (l-lc), Lake-bottom Facies of Glacial Lake Cornwall Deposits (l-lcw), Lake-bottom Facies of Glacial Lake Danbury Pond Brook Stage Deposits (l-ldp), Lake-bottom Facies of Glacial Lake Danbury Pumpkin Hill Stage Deposits (l-ldh), Lake-bottom Facies of Glacial Lake Danbury Saugatuck Divide Stage Deposits (l-lds), Lake-bottom Facies of Glacial Lake Hollenbeck Deposits (l-lh), Lake-bottom Facies of Glacial Lake Norfolk Deposits (l-ln), Lake-bottom Facies of Glacial Lake Oneco Deposits (l-lon), Lake-bottom Facies of Glacial Lake Pachaug Deposits (l-lp), Lake-bottom Facies of Glacial Lake Pootatuck Deposits (l-lpt), and Lake-bottom Facies of Glacial Lake Voluntown Deposits (l-lvo).
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This category includes the following Quaternary Geology map units: Lake-bottom Facies of Gardner Lake Deposits (l-gl), Lake-bottom Facies of Uncorrelated Deposits of Ice Dammed Ponds (l-ip), and Lake-bottom Facies of Wauregan Deposits (l-wr).
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This category includes the following Quaternary Geology map units: Glacial Lake Hitchcock Lake-bottom Deposits (lhlb), Glacial Lake Middletown Lake-bottom Deposits (lmb), Lake-bottom Facies of Glacial Lake Ellington Deposits (l-le), Lake-bottom Facies of Glacial Lake Great Falls Deposits (l-lg), Lake-bottom Facies of Glacial Lake Kenosia Deposits (l-lk), Lake-bottom Facies of Glacial Lake Pomperaug Deposits (l-lpg), Lake-bottom Facies of Glacial Lake Quinebaug Deposits (l-lqb), Lake-bottom Facies of Glacial Lake Quinnipiac Deposits (l-lq), Lake-bottom Facies of Glacial Lake Somers Deposits (l-lso), and Lake-bottom Facies of Glacial Lake Southington Deposits (l-ls).
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This category includes the following Quaternary Geology map units: Lake-bottom Facies of Danielson Deposits (l-da), Lake-bottom Facies of Lower Willimantic River Deposits (l-wrl), Lake-bottom Facies of Pequonnock-Farmill River Deposits (l-pf), Lake-bottom Facies of Quinebaug Valley Deposits (l-qb), Lake-bottom Facies of Skungamaug River Deposits (l-sk), and Lake-bottom Facies of Upper Wepawaug River Deposits (l-wu).
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This category includes the following Quaternary Geology map unit: Stream-terrace Deposits (st).
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This category includes the following Quaternary Geology map units: Swamp Deposits (sw) and Tidal-marsh Deposits (sm).
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This category includes the following Quaternary Geology map unit: Talus (ta).
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This category includes the following Quaternary Geology map unit: Thick Till Deposits (tt).
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This category includes the following Quaternary Geology map unit: Thin Till Deposits (t).
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This category includes the following Quaternary Geology map unit: Lake-bottom Facies of Undifferentiated Meltwater Deposits (l-u).
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This category includes the following Quaternary Geology map unit: Glaciofluvial Facies of Undifferentiated Meltwater Deposits (f-u).
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This category includes the following Quaternary Geology map unit: Undifferentiated Meltwater Deposits (u).
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This category includes the following Quaternary Geology map unit: Water (w).
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Internet Mapping Software Legend - A text field used to classify and symbolize Quaternary Geology polygon features into broad categories, more suitable for use with Internet mapping applications. The IMS_LEGEND attribute condenses the 285 Quaternary map units (QUPOLY_COD values) into 11 broad categories of deposits (based in part on depositional system).
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
This category includes Quaternary Geology map units having the following depositional system (DEPOSITION) value: Postglacial Deposits (Holocene). This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) value: Artificial Fill..
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Early Postglacial Deposits (Late Wisconsinan, Early Holocene). This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Inland Dune Deposits and Stream Terrace Deposits.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Glacial Ice Laid Deposits (Late Wisconsinan, Illinoian). This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) value: End Moraine Deposits.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Deposits of Major Ice-dammed Lakes and Deposits of Related Series of Ice Dammed Ponds. This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Deposits of Ice Dammed Lakes, Deposits of Ice Dammed Ponds, Glaciofluvial Deposits graded to Ice Dammed Lakes, Lake Bottom Deposits of Ice Dammed Lakes and , Lake Bottom Deposits of Ice Dammed Ponds.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Deposits of Distal Meltwater Streams, Deposits of Proximal Meltwater Streams and Deposits of Related Series of Sediment Dammed Ponds. This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Deposits of Distal Meltwater Streams and Deposits of Proximal Meltwater Streams.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Postglacial Deposits (Holocene).This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Coastal Beach and Dune Deposits, Floodplain Alluvium, Swamp or Tidal Marsh Deposits, and Talus.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Deposits of Major Sediment-dammed Lakes and Deposits of Related Series of Sediment Dammed Ponds. This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Deposits of Sediment Dammed Lakes, Deposits of Sediment Dammed Ponds, Glaciofluvial Deposits graded to Sediment Dammed Lakes, Lake Bottom Deposits of Sediment Dammed Lakes, and Lake Bottom Deposits of Sediment Dammed Ponds.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Glacial Ice Laid Deposits (Late Wisconsinan, Illinoian). This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) value: Thick Till.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Glacial Ice Laid Deposits (Late Wisconsinan, Illinoian). This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) value: Till.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Undiffentiated Meltwater Deposits. This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) values: Undifferentiated Glacial Lake-Bottom Deposits, Undifferentiated Glaciofluvial Deposits, and Undifferentiated Meltwater Deposits.
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This category includes Quaternary Geology map units with the following depositional system (DEPOSITION) value: Water. This definition also correponds to map units with the following ArcView Legend (AV_LEGEND) value: Water.
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Depostional System Polygon Code - The key field used to classify Depositional Systems units. Attribute values are major organizational system for Quaternary geology map units. Depositional system descriptions (which are particularly detailed for the 6 major depositional systems for glacial meltwater deposits) are included as attribute value definitions.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Postglacial Deposits (Holocene) - includes artificial fill, flood-plain alluvium, swamp, tidal-marsh, talus, and coastal beach and dune deposits.
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Early Postglacial Deposits (late Wisconsinan, Early Holocene) - includes stream terrace, inland dune deposits. Also includes submerged fluvial-estuarine, channel-fill deposits and submerged marine deltaic deposits which are part of the Long Island Sound Basin data layers.
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Deposits Of Major Ice-Dammed Lakes - Paleogeographic setting: Gently sloping, relatively wide valleys and basins with drainage outlets to the north. Main valleys commonly fed by steeper tributary valleys. Lakes impounded in these valleys and basins when ice margin blocked drainage outlet to the north. Lakes spilled through cols floored in till and (or) bedrock across drainage divides. Some lakes had two or three stages as northward retreat uncovered lower spillways out of the basin. Deposits: Deltaic, fluvial, and lake-bottom sedimentary facies are included in these deposits. Delta-tributary fluvial sediments are indicated by f- prefix in QUPOLY_COD; lake-bottom sediments are indicated by l- prefix in QUPOLY_COD. Most prevalent morphosequences are ice-marginal deltas, but ice-marginal and near-ice-marginal fluviodeltaic sequences also occur; locally, ice-marginal lacustrine fan deposits are found. Lake-bottom deposits associated with multiple deltaic morphosequences cover large areas.
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Deposits Of Major Sediment-Dammed Lakes - Paleogeographic setting: Gently sloping, relatively wide valleys and basins that drained to the south, away from the ice margin. Relatively large glacial lakes formed in these valleys and basins behind thick sediment dams that filled narrower sections of the valleys. Dams most commonly were composed of ice-marginal meltwater sediments (usually deltaic) deposited at slightly earlier ice-margin positions in the valleys. Lakes developed in wider sections of valleys or in basins within valleys and were commonly fed by streams in tributary valleys to the lakes. Spillways for some lakes were over their sediment dams, in which case the lake-level lowered continuously during the life of the lake because the spillway was across easily erodible sand and gravel deposits. Other lakes had spillways with their base in bedrock across basin divides that were lower in altitude than the surface of the sediment dam blocking the valley; lake levels were stable throughout the life of these lakes. Deposits: Deltaic, fluvial, and lake-bottom sediments are included in these deposits. Delta-tributary fluvial sediments indictated by f- prefix; lake-bottom sediments indicated by l- prefix. Morphosequence types include ice-marginal deltaic, ice-marginal fluviodeltaic, and near-ice-marginal fluviodeltaic deposits; locally, ice-marginal lacustrine fan deposits occur; glacial Lake Hitchcock deposits include meteoric deltas. Lake-bottom deposits associated with multiple deltaic morphosequences cover large areas.Stratigraphic arrangement of deposits: Deltas in this depositional system commonly have free fronts with lake-bottom sediments beyond that separate younger deltas from older ones. Altitudes of deltas in most of these deposits rise to the northwest at a rate less than the slope of postglacial tilt, a result of lowering spillway levels. Exceptions are deltas of glacial Lake Quinebaug and stable-level deltas of glacial Lake Hitchcock; these deltas rise to the northwest at a rate equal to the slope of postglacial tilt and reflect stable lake levels controlled by bedrock spillways. Fluvial facies within fluviodeltaic morphosequences occur either in valleys tributary to the main basin or in wide valleys that contained glacial lakes.
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Deposits Of Related Series Of Ice-Dammed Ponds - Paleogeographic setting: Steeper, small valleys that slope to the north toward ice margin. Series of small lakes or ponds, impounded to the north by ice margin in one or several north-sloping valleys. Multiple spillways cut into till or bedrock across divides are at successively lower altitudes to the north. A few units formed in this depositional setting were built in a single north-draining valley, into only one small lake; most, however, formed in a series of lakes, which lowered successively to the north in several valleys descending from particular major or minor divides. Each group of ponds formed during retreat of the ice margin from impingement against the divide, and before uncovering of lower drainage outlets. Deposits: Predominantly deltaic sedimentary facies are included in these deposits. Lake-bottom facies occur locally beneath the deltas, but are not exposed at the surface. Ice-marginal deltas are the only type of morphosequences present. Some ice-marginal deltas have fluvial feeder eskers. Stratigraphic arrangement of deposits: Deltas generally do not have free fronts because the delta commonly completely filled the small body of water into which it was built and distal sand extended into the spillway entrance. Lake-bottom sediment consists mostly of bottomset beds (rather than extensive varved silts and clays) and occurs only beneath deltaic sediments. In any one valley, where deltas were built into lowering series of ponds, deltas commonly are contiguous; each younger delta surface laps against ice-contact proximal slope of the older delta.
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Deposits Of Related Series Of Sediment-Dammed Ponds - Paleogeographic setting: Many valleys in Connecticut sloped to the south away from the ice margin. In narrower sections of these south-sloping valleys, series of small lakes developed sequentially as a result of northward ice retreat. Each pond was dammed behind (to the north of) the valley-blocking body of sediment that filled the next previous pond. In steeper sections of these valleys, meltwater streams fed a small lake farther down the valley. Spillways for each small lake were over sediment dams; these spillways commonly no longer exist because most of the sediment was removed by distal meltwater and ancestral streams in each valley. The process of degradation and entrenchment of ice-marginal deposits in these narrow south-sloping valleys was aided by a lowering base level (glacial Lake Connecticut) in Long Island Sound. Deposits: Predominantly deltaic and fluvial sediments; lake-bottom sediments occur locally beneath deltaic sediments but are not exposed at the surface. Ice-marginal deltaic, fluviodeltaic, and deltaic-fluvial morphosequences are present; near-ice-marginal fluviodeltaic deposits occur rarely. Stratigraphic arrangement of deposits: Deltas in this depositional system generally do not have free fronts; deltaic sediments commonly filled small ponds and are contiguous with the ice-marginal heads of previous morphosequences in the valley. Lacustrine sediments consist mostly of bottomset beds and are present only beneath coarser deltaic sediments. Deltaic surfaces and topset-foreset contacts within a map unit commonly rise up valley at a rate greater than the slope of postglacial tilt. Because of thick fluvial-topset aggradation in each deltaic sediment dam, levels of ponding were successively higher up valley. Fluvial sediments within fluviodeltaic morphosequences occur in steeper sections of some valleys where the till and (or) bedrock floor is at shallow depths. Deltaic-fluvial morphosequences occur in sections of gentler gradient in some valleys; in these places, fluvial beds overlie deltaic beds and may overlap from one morphosequence to other ice-marginal deltas farther down the valley. In many valleys, only remnant deposits of the SP depositional system remain, especially in longer river valleys of the Eastern and Western Highlands such as the Thames, lower Connecticut, Naugatuck, and Housatonic.
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Deposits Of Proximal Meltwater Streams - Paleogeographic setting: South-draining valleys that had a relatively steep gradient and were not tributary to any glacial lake. These valleys were steep enough to avoid ponding, but not so steep that the sediment load of the meltwater stream was carried beyond. Outwash plains, broad areas of meltwater-stream deposition in front of moraines, also are included. Deposits: Fluvial sediments in ice-marginal and near-ice-marginal fluvial morphosequences. In general, these deposits are coarse grained (gravel and sand) and only 3 to 9 m (10 to 30 ft) thick (rarely as much as 15 m (50 ft) thick in moraine-proximal outwash deposits). Stratigraphic arrangement of deposits: Deposits have relatively steep surface gradients, generally on the order of 2 to 7.5 m/km (10 to 40 ft/mi). In Connecticut, deposits of this depositional system are relatively uncommon; the best-developed ice-marginal fluvial deposits occur as parts of fluviodeltaic morphosequences in valleys tributary to glacial lakes and therefore are included in glaciolacustrine systems. Ice-marginal fluvial deposits on outwash plains in front of moraines also are uncommon; only one small deposit is known to occur in Connecticut (part of unit lmwv in the Broad Brook quadrangle), but extensive deposits in front of the Fishers Island-Charlestown moraine occur in the Rhode Island (part of the Watch Hill quadrangle) and in the New York part of the New London quadrangle and are shown on the map.
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Deposits Of Distal Meltwater Streams - Paleogeographic setting: South-draining valleys and basins after ice-marginal lakes had drained, allowing distal meltwater to incise, terrace, and redeposit sediment of slightly older ice-marginal meltwater deposits. In some cases, these distal meltwater streams originated at the glacier margin, which was more than 8 km (5 mi) away; in other cases, a glacial lake separated the glacier margin from the site of meltwater-terrace deposition, and the meltwater stream issued from the spillway of a glacial lake. Deposits: Distal fluvial sediments not traceable to an ice-marginal head. Deposits commonly consist of sand and fine gravel only 1 to 3 m (3 to 10 ft) thick; as much as 9 m (30 ft) thick in more extensive map units. Sediment is commonly lithologically distinct from underlying deposits. Stratigraphic arrangement of deposits: Deposits occur on terraces erosionally inset into ice-marginal (generally glacio-lacustrine) deposits that are older and higher in altitude; these terraces extend for relatively long distances farther down the valleys, and may be entrenched through several higher and older units. These units are the most extensive glaciofluvial deposits in Connecticut.
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Undiffentiated Meltwater Deposits
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Glacial Ice Laid Deposits (late Wisconsinan, Illinoian) - includes thin till, thick till, and end moraine deposits.
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Water
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Deposition - This attribute provides the full text name for the values stored in the DSPOLY_COD (Depositional System) field. Deposition is the English language equivalent of (decodes) the DSPOLY_COD field. For example, DSPOLY_COD and DEPOSITION attribute values for the same polygon feature are IP and Deposits Of Related Series Of Ice Dammed Ponds, respectively.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Surficial Materials Polygon Code - The key field used to classify surficial materials units. Attribute values are mostly single characters in length, except for stacked map units that include forward slashes (/) between the different textural types such as A/F, A/F/G, and A/F/SG.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Floodplain Alluvium - Sand, gravel, silt, and some organic material, on the floodplains of modern streams. The texture of alluvium commonly varies over short distances both laterally and vertically, and is often similar to the texture of adjacent glacial deposits. Along smaller streams, alluvium is commonly less than 5 ft thick. The most extensive deposit of alluvium on the map is along the Connecticut River where the texture is predominantly fine to very fine sand and silt; here and along other larger rivers, it may be as much as 25 ft thick. Alluvium typically overlies thicker glacial stratified deposits, the general texture of which is indicated by the stacked unit.
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Alluvium overlying Fines
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Alluvium overlying Fines overlying Gravel
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Alluvium overlying Fines overlying Sand
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Alluvium overlying undifferentiated Fine deposits overlying coarse deposits (Sand and Gravel)
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Alluvium overlying Sand
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Alluvium overlying Sand overlying Fines
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Alluvium overlying Sand overlying Sand and Gravel
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Alluvium overlying undifferentiated coarse deposits (Sand and Gravel)
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Alluvium overlying undifferentiated coarse deposits (Sand and Gravel) overlying Fine deposits
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Alluvium overlying Sand and Gravel overlying Sand
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Alluvium overlying Sand and Gravel overlying Sand overlying Fines
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Artificial Fill - Earth materials and manmade materials that have been artificially emplaced. Artificial fill is common throughout the map area but has been shown on this map only where extensive areas of 'made land' occur, principally along the coast.
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Beach deposits - Sand and and gravel deposited along the shoreline by waves and currents and by wind action. The texture of beach deposits varies over short distances and is generally controlled by the texture of nearby glacial materials exposed to wave action. Beach deposits are generally well sorted and rarely more than a few feet thick. Many sand beaches along the Connecticut coast have been 'restored'; these have not been distinguished from natural beaches on this map; however, extensive beaches that consist totally of 'made-land' are mapped as artificial fill.
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Fines (very fine sand, silt, and clay) - Composed of well-sorted, thin layers of alternating silt and clay, or thicker layers of very fine sand and silt. Very fine sand commonly occurs at the surface and grades downward into rhythmically bedded silt and clay varves (lake-bottom deposits)
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Fines overlying Gravel
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Fines overlying Sand-- Fines of variable thickness, commonly in thinly bedded layers overlie sand of variable thickness (distal lake-bottom deposits overlying slightly older more delta-proximal lacustrine sediment)
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Fines overlying Sand and Gravel - Fines of variable thickness, commonly in thinly bedded layers overlie sand and gravel of ariable thickness (lake-bottom deposits overlying slightly older collapsed proximal fluvial or deltaic deposits); in a few places sand or sand and gravel, generally less than 25 ft thick occurs on top of the F/SG unit and is indicated as S/F/SG and SG/F/SG on the map, respectively
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Gravel - Composed mainly of gravel-sized particles; cobbles and boulders predominate; minor amounts of sand within gravel beds, and sand comprises few separate layers. Gravel layers generally are poorly sorted and bedding commonly is distorted and faulted due to postdepositional collapse related to melting of ice. Gravel deposits are shown only where observed in the field; additional gravel deposits may be expected, principally in areas mapped as unit SG (proximal fluvial deposits or delta-topset beds)
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Gravel overlying Fines - Gravel is generally less than 20 ft thick, horizontally bedded and overlies thicker thinly bedded fines (proximal fluvial deposits overlying lake-bottom sediments)
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Gravel overlying Sand-- Gravel is generally less than 20 ft thick, horizontally bedded, and overlies thicker, inclined layers of sand (proximal deltaic deposits)
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Gravel overlying Sand overlying Fines - Gravel is generally less than 20 ft thick, horizontally bedded and overlies thicker inclined beds of sand which in turn overlie fines of variable thickness (proximal deltaic deposits overlying lake-bottom sediments)
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Gravel overlying Sand and Gravel - Gravel is generally less than 20 ft thick, horizontally bedded, and overlies thicker, inclined layers of sand and gravel (proximal deltaic deposits)
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Gravel overlying Sand and Gravel overlying Sand
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Sand - Composed mainly of very coarse to fine sand, commonly in well-sorted layers. Coarser layers may contain up to 25 percent gravel particles, generally granules and pebbles; finer layers may contain some very fine sand, silt, and clay (delta-foreset beds, very distal fluvial deposits, or windblown sediment)
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Sand overlying Fines - Sand is of variable thickness, commonly in inclined foreset beds and overlies thinly bedded fines of variable thickness (distal deltaic deposits overlying lake-bottom sediment)
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Sand overlying Fines overlying Sand and Gravel
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Sand overlying Gravel - Sand of variable thickness overlies gravel of variable thickness (younger distal deltaic or fluvial sediments overlying older, more proximal fluvial or deltaic sediments)
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Sand overlying Sand and Gravel - Sand of variable thickness overlies sand and gravel of variable thickness (distal deltaic or fluvial sediments overlying slightly older proximal fluvial or deltaic sediments)
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Sand and gravel - Composed of mixtures of gravel and sand within individual layers and as alternating layers. Sand and gravel layers generally range from 25 to 50 percent gravel particles and from 50 to 75 percent sand particles. Layers are well to poorly sorted; bedding may be distorted and faulted due to postdepositional collapse. It is likely that some deposits within this map unit actually are gravel or sand and gravel overlying sand. It is less likely that some of these deposits are sand (fluvial deposits or delta-topset beds)
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Sand and Gravel overlying Fines - Sand and gravel is generally less than 20 ft thick, horizontally bedded and overlies thicker thinly bedded fines (fluvial meltwater terrace deposits overlying lake-bottom sediment)
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Sand and Gravel overlying Fines overlying Sand and Gravel
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Sand and Gravel overlying Sand - Sand and gravel is generally less that 20 ft thick, horizontally bedded, and overlies thicker, inclined layers of sand (deltaic deposits)
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Sand and Gravel overlying Sand overlying Fines - Sand and gravel is generally less than 20 ft thick, horizontally bedded and overlies thicker inclined beds of sand which in turn overlie thinly bedded fines of variable thickness (deltaic deposits overlying lake-bottom sediment)
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Sand and Gravel overlying Sand overlying Sand and Gravel - Sand and gravel is generally less than 20 ft thick, horizontally bedded, and overlies thicker inclined layers of sand; thickness of sand and gravel at the base of the section is variable (deltaic deposits overlying slightly older, more proximal deposits)
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Salt-marsh and tidal-marsh deposits - Peat and muck interbedded with sand and silt, deposited in environments of low wave energy along the coast and in river estuaries. Marsh deposits are dominantly peat and muck, generally a few feet to 35 ft thick. In the major estuaries marsh deposits may overlie estuarine deposits which are sand and silt with minor organic material as much as 40 - 90 ft thick. These deposits are generally underlain by the glacial material shown adjacent on the map; either till or sand and gravel. Where they are known or inferred to be underlain by sand or fines, they are shown on the map by stacked units.
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Salt-marsh and tidal-marsh deposits overlying Fines
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Salt-marsh and tidal-marsh deposits overlying Sand overlying Fines
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Swamp deposits - Muck and peat that contain minor amounts of sand, silt, and clay, accumulated in poorly drained areas. Most swamp deposits are less than about 10 ft thick. Swamp deposits are underlain by glacial deposits or bedrock. They are often underlain by glacial till even where they occur within glacial meltwater deposits. Where swamp deposits are known or inferred to be underlain by sand and/or fines, they are shown on the map by the stacked unit.
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Swamp deposits overlying Fines
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Swamp deposits overlying Fines overlying Sand
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Swamp deposits overlying Sand
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Swamp deposits overlying Sand overlying Fines
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Swamp deposits overlying Sand overlying undifferentiated coarse deposits (Sand and Gravel)
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Swamp deposits overlying undifferentiated coarse deposits (Sand and Gravel)
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Thin Till - areas where till is generally less than 10-15 ft thick and including areas of bedrock outcrop where till is absent. Predominantly upper till; loose to moderately compact, generally sandy, commonly stony. Two facies are present in some places; a looser, coarser-grained ablation facies, melted out from supraglacial position; and a more compact finer-grained lodgement facies deposited subglacially. In general, both facies of upper till derived from the red Mesozoic sedimentary rocks of the central lowland of Connecticut are finer-grained, more compact, less stony and have fewer surface boulders than upper till derived from crystalline rocks of the eastern and western highlands.
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Talus - Loose, angular blocks (mostly boulders) accumulated by rockfall at the bases of steep bedrock cliffs. Talus forms steep unstable slopes and is generally less than 10 ft thick. It occurs most extensively along the linear basalt and diabase ridges within the central lowland.
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Sandy Till, Sand and Gravel, some areas of dense surface bolders (End moraine deposits) - Composed predominantly of ablation facies sandy upper till; lenses of stratified sand and gravel occur locally within the till. Surface boulders on end moraine deposits are generally more numerous than on adjacent till surfaces; dense concentrations of boulders are present in some places. Deposits occur as free-standing hummocky landforms, commonly in elongate ridges that trend NNE - SSW, and range in thickness from 10 to 60 ft.
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Thick Till - areas where till is greater than 10-15 ft thick and including drumlins in which till thickness commonly exceeds 100 ft (maximum recorded thickness is about 200 ft). Although upper till is the surface deposit, the lower till constitutes the bulk of the material in these areas. Lower till is moderately to very compact, and is commonly finer-grained and less stony than upper till. An oxidized zone, the lower part of a soil profile formed during a period of interglacial weathering, is generally present in the upper part of the lower till. This zone commonly shows closely-spaced joints that are stained with iron and manganese oxides.
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Water - Defined as streams, lakes, ponds, bays, and estuaries greater than 5 acres in size. Surficial Material water polygon features are outlined by Surficial Material line features with a SMARC_COD attribute value of 2 (for Hydrography Shoreline).
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Surficial Materials - The SURFM_POLY attribute includes longer text values for the mostly single-character values stored in the SMPOLY_COD field. SURFM_POLY is the English language equivalent of (decodes) the SMPOLY_COD field. For example, SMPOLY_COD and SURFM_POLY attribute values for the same polygon feature are G and Gravel, respectively. SURFM_POLY attribute values for stacked map units include forward slashes (/) between the different textural types such as Aluvium/Fines, Aluvium/Fines/Gravel, and Alluvium/Fines/Sand+Gravel.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Surficial Materials Description - Based on the SMPOLY_COD attribute, a longer decoded description of the map unit than that provided by the SURFM_POLY attribute. For example, SMPOLY_COD, SURFM_POLY, and SM_DESC attribute values for the same polygon feature are A/S, Aluvium/Sand, and Aluvium overlying Sand, respectively.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Calculated area of polygon feature in acres. Note, ACREAGE values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Calculated area of polygon feature in square miles. Note, AREA_SQMI values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
U.S. Geological Survey and State of Connecticut, Department of Environmental Protection
Polygon codes Surficial Materials unit (SMPOLY_COD), Quaternary Geologic unit (QUPOLY_COD), and Depositional System (DSPOLY_COD) represent the underlying classification scheme for units completely named in their respective de-code fields and described further in this metatdata document, Surficial Materials metadata, and SIM_2784.pdf (pamplet for the Quaternary map, Stone and others, 2005). These text files have been excerpted from the text on sheet 1 of the Surficial Materials Map of Connecticut and in the pamphlet of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin. They have been modified as necessary for use with the 1:24,000 scale digital data, and are not considered as valid substitutes for the information found on the published maps.
Stone, J.R., Schafer, J.P., London, E.H. and Thompson, W.B., 1992, Surficial Materials Map of Connecticut, U.S. Geological Survey special map, 2 sheets, scale 1:125,000. Stone, J.R., Schafer, J.P., London, E.H., DiGiacomo-Cohen, M.L., Lewis, R.S. and Thompson, W.B., 2005, Quaternary Geologic Map of Connecticut and Long Island Sound Basin, U.S. Geological Survey Scientific Investigaions Map 2784, 2 sheets, scale 1:125,000.
79 Elm Street
Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata.
The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.
Long Island Sound Resource Center, UConn Avery Point, 1080 Shennecossett Rd.