The Hydrogeologic Terranes dataset includes separate polygon and line feature classes. The polygon feature class divides the glaciated United States into seventeen distinct terranes using a geologically based approach. Each terrane contains Quaternary sediment that is derived from a common depositional history and can be characterized by texture and thickness. Delineation of hydrogeologic terranes was based on an interpretation of existing geologic mapping of surficial and Quaternary deposits, and thickness of unconsolidated material. Overall thickness of Quaternary sediment was used to qualitatively rank the generalized complexity of geologic framework in each terrane: "lower" complexity (assigned a terrane code = 1), "moderate" (code = 2), and "higher" complexity (code = 3). Letter designations appended to the numeric codes (e.g., 1A, 3C) differentiate terranes of similar complexity. Two unique areas, where thick, stratified, coarse-grained sediment dominates, were assigned code = 4. The line feature class of the Hydrogeologic Terranes dataset identifies terrane boundary line types. Possible values are: (1) sediment thickness contrast boundary, (2) major river boundary, (3) maximum extent of glacial ice, and (4) extent of Late Wisconsinan glacial ice.

The GESS data includes polygon file with multiple attributes which describe the lithology, geomorphology, and related depositional environment of Quaternary-age surfical sediments in the glaciated conterminous United States. These attributes include: the map unit (GESS_MU), a geomorphic modifier (GESS_Modifier), a sediment stratification indicator (SedStrat), and a a sediment texture classification (Texture6). Possible GESS_MU values include: alluvial sediment, colluvial sediment, eolian sediment, lacustrine sediment, marine sediment, organic sediment, outwash, ice-contact deposits, island, residual soils, soliflucted sediment, till, bedrock, fill, and water. Possible GESS_Modifier values include: e (end moraine), g (ground moraine), s (stagnation moraine), d (discontinuous or attenuated), or f (soliflucted). Possible SedStrat values include "0" (unstratified, and "1" (stratified). Possible values for Texture6 include mostly sandy, sandy-silty, mostly silty, silty-clayey, mostly clayey, and mostly organic.

The GESS data includes polygon file with multiple attributes which describe the lithology, geomorphology, and related depositional environment of Quaternary-age surfical sediments in the glaciated conterminous United States. These attributes include: the map unit (GESS_MU), a geomorphic modifier (GESS_Modifier), a sediment stratification indicator (SedStrat), and a a sediment texture classification (Texture6). Possible GESS_MU values include: alluvial sediment, colluvial sediment, eolian sediment, lacustrine sediment, marine sediment, organic sediment, outwash, ice-contact deposits, island, residual soils, soliflucted sediment, till, bedrock, fill, and water. Possible GESS_Modifier values include: e (end moraine), g (ground moraine), s (stagnation moraine), d (discontinuous or attenuated), or f (soliflucted). Possible SedStrat values include "0" (unstratified, and "1" (stratified). Possible values for Texture6 include mostly sandy, sandy-silty, mostly silty, silty-clayey, mostly clayey, and mostly organic.

The bedrock geology for the Glacial Environments and Surficial Sediments (GESS) geodatabase is an amalgamation of several “Integrated Geologic Map Databases for the United States” (Dicken and others, 2008; Ludington and others, 2007; Nicholson and others, 2007-1,-2,-3; Stoeser and others, 2007). Using the LITH62 and LITH62MINO attribute values from that series of maps and the associated lithclass 6.2 code text descriptions from the geodatabase, spatial elements of that geodatabase were grouped. A new GESS attribute was created, “Litho_class,” and each spatial element was given a Litho_class value of non-carbonate sedimentary rock, carbonate rock, non-carbonate metamorphic rock, volcanic rock, plutonic rock, or unconsolidataed (material).

The bedrock geology for the Glacial Environments and Surficial Sediments (GESS) geodatabase is an amalgamation of several “Integrated Geologic Map Databases for the United States” (Dicken and others, 2008; Ludington and others, 2007; Nicholson and others, 2007-1,-2,-3; Stoeser and others, 2007). Using the LITH62 and LITH62MINO attribute values from that series of maps and the associated lithclass 6.2 code text descriptions from the geodatabase, spatial elements of that geodatabase were grouped. A new GESS attribute was created, “Litho_class,” and each spatial element was given a Litho_class value of non-carbonate sedimentary rock, carbonate rock, non-carbonate metamorphic rock, volcanic rock, plutonic rock, or unconsolidataed (material).

Connecticut Quaternary Geology Geologic Basin Divides includes the drainage basins divides appearing on Sheet 1 of the The Quaternary Geologic Map of Connecticut and Long Island Sound Basin (Stone and others, 2005) 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/o

This data release is a compilation of the digital products from a hydrogeologic framework of the glaciated conterminous United States that were constructed to portray sediment and aquifer characteristics within this area. These digital products are described in Yager and others (2018).