The Sediment and Aquifer Characteristics dataset includes two, grid-based polygon feature classes. The first class uses a five-kilometer grid to show the density of lithologic logs available for analysis. The second class contains attributes that characterize either Quaternary sediment in the glaciated conterminous United States or aquifer material within it. The attributes are derived from lithologic logs obtained from boreholes and wells. The polygons were delineated by a constrained, kriging-based interpolation based on the distribution of map units in the source Surficial Geologic Units dataset using a grid-based algorithm to interpolate between the point data, as defined in the processing steps.

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).

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).

The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity based horizontal hydraulic conductivity and transmissivity of coarse-grained sediment within the glacial deposits, texture-based estimated equivalent horizontal and vertical hydraulic conductivity of the glacial deposits, and texture-based estimated equivalent transmissivity of the glacial deposits. The raster data sets are available for download in both American Standard Code for Information Interchange (ASCII) and Environmental Systems Research Institute (ESRI) Grid formats. These data have value for regional studies of water availability and aquifer vulnerability.

The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity based horizontal hydraulic conductivity and transmissivity of coarse-grained sediment within the glacial deposits, texture-based estimated equivalent horizontal and vertical hydraulic conductivity of the glacial deposits, and texture-based estimated equivalent transmissivity of the glacial deposits. The raster data sets are available for download in both American Standard Code for Information Interchange (ASCII) and Environmental Systems Research Institute (ESRI) Grid formats. These data have value for regional studies of water availability and aquifer vulnerability.

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).

The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity based horizontal hydraulic conductivity and transmissivity of coarse-grained sediment within the glacial deposits, texture-based estimated equivalent horizontal and vertical hydraulic conductivity of the glacial deposits, and texture-based estimated equivalent transmissivity of the glacial deposits. The raster data sets are available for download in both American Standard Code for Information Interchange (ASCII) and Environmental Systems Research Institute (ESRI) Grid formats. These data have value for regional studies of water availability and aquifer vulnerability.

The glacial aquifer system of the United States encompasses all or parts of 25 states and is the most widely used supply of drinking water in the Nation (Maupin and Barber, 2005; Maupin and Arnold, 2010). A series of seven raster data sets were derived from a database of water-well drillers' records that was compiled in partial fulfillment of the goals of the U.S. Geological Survey’s Groundwater Availability and Use assessment program (U.S. Geological Survey, 2002). They contain hydrogeologic information for areas of the U.S. that are north of the southern limit of Pleistocene glaciation, including the total thickness of glacial deposits, thickness of coarse-grained sediment within the glacial deposits, specific-capacity based horizontal hydraulic conductivity and transmissivity of coarse-grained sediment within the glacial deposits, texture-based estimated equivalent horizontal and vertical hydraulic conductivity of the glacial deposits, and texture-based estimated equivalent transmissivity of the glacial deposits. The raster data sets are available for download in both American Standard Code for Information Interchange (ASCII) and Environmental Systems Research Institute (ESRI) Grid formats. These data have value for regional studies of water availability and aquifer vulnerability.

The State of Alaska's Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska's statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. For the geochemical part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. For this report, DGGS funded reanalysis of 1,682 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from an area covering the western half of the Wrangellia Terrane in the Anchorage, Gulkana, Healy, Mt. Hayes, Nabesna, and Talkeetna Mountains quadrangles of south-central Alaska. USGS was responsible for sample retrieval from the Denver warehouse through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical databases of both agencies.