A combination of long-term daily temperature records and depth to bedrock measurements were used to parametrize one-dimensional models of shallow aquifer vertical heat transport in Shenandoah National Park, VA, USA. Depth to bedrock can directly influence shallow aquifer flow and thermal sensitivity, but is typically ill-defined along the stream corridor in steep mountain catchments. We employed rapid, cost-effective passive seismic measurements to evaluate the variable thickness of the shallow colluvial and alluvial aquifer sediments along a headwater stream supporting coldwater-dependent brook trout (Salvelinus fontinalis) in Shenandoah National Park. The methods are fully documented in the associated journal article, Briggs, M.A., J.W. Lane, C.D. Snyder, E.A. White, Z.C. Johnson, D.L. Nelms, and N.P. Hitt, 2017, Shallow mountain bedrock limits seepage-based headwater climate refugia, Limnologica, https://dx.doi.org/10.1016/j.limno.2017.02.005. This Data Release includes seismic data collected as part of the study.

A combination of long-term daily temperature records and depth to bedrock measurements were used to parameterize one-dimensional models of shallow aquifer vertical heat transport in Shenandoah National Park, VA, USA. Spatially discontinuous roving water surface and bank temperatures surveys were performed with a handheld thermal infrared camera in September and December 2015 along the main channel of a headwater stream supporting coldwater-dependent brook trout (Salvelinus fontinalis). We also installed vertical arrays of thermal data loggers to estimate bulk thermal diffusivity of the saturated alluvium at two stations in the upper trout section. The methods are fully documented in the associated journal article, Briggs, M.A., J.W. Lane, C.D. Snyder, E. White, Z.C. Johnson, D.L. Nelms, and N.P. Hitt, 2017, Shallow mountain bedrock limits seepage-based headwater climate refugia, Limnologica, https://dx.doi.org/10.1016/j.limno.2017.02.005. This Data Release includes temperature measurements collected as part of the study. The directory RAW_DATA contains the measured temperature time series at streambed, stream, and air locations as described in the local read.me file. The OUTPUT directory contains the processed temperature time series and VFLUX2 calculations of thermal diffusivity (Ke) from streambed data, and annual temp signal amplitude/phase lag from stream/air data are listed.

A combination of long-term daily temperature records and depth to bedrock measurements were used to parameterize one-dimensional models of shallow aquifer vertical heat transport in Shenandoah National Park, VA, USA. Spatially discontinuous roving water surface and bank temperatures surveys were performed with a handheld thermal infrared camera in September and December 2015 along the main channel of a headwater stream supporting coldwater-dependent brook trout (Salvelinus fontinalis). We also installed vertical arrays of thermal data loggers to estimate bulk thermal diffusivity of the saturated alluvium at two stations in the upper trout section. The methods are fully documented in the associated journal article, Briggs, M.A., J.W. Lane, C.D. Snyder, E. White, Z.C. Johnson, D.L. Nelms, and N.P. Hitt, 2017, Shallow mountain bedrock limits seepage-based headwater climate refugia, Limnologica, https://dx.doi.org/10.1016/j.limno.2017.02.005. This Data Release includes temperature measurements collected as part of the study. The directory RAW_DATA contains the measured temperature time series at streambed, stream, and air locations as described in the local read.me file. The OUTPUT directory contains the processed temperature time series and VFLUX2 calculations of thermal diffusivity (Ke) from streambed data, and annual temp signal amplitude/phase lag from stream/air data are listed.

In July 2016, July 2019, and March 2020, 318 seismic recordings were acquired at locations within Shenandoah National Park, Virginia, using MOHO Tromino Model TEP-3C three-component seismometers to assess depth to bedrock using the HVSR method. This method requires a measurement of estimate of shear wave velocity, which depends on the regolith sediment composition and density, for the conversion of measured resonance frequency to a depth to bedrock. Shear wave velocities were calculated for sediment in Shenandoah NP at locations where regolith thickness is known (e.g. at documented boreholes). The locations in this study were generally selected to characterize the depths to bedrock adjacent to streams monitored for coupled temperature and flow dynamics related to several ongoing USGS projects.

In July 2016, July 2019, and March 2020, 318 seismic recordings were acquired at locations within Shenandoah National Park, Virginia, using MOHO Tromino Model TEP-3C three-component seismometers to assess depth to bedrock using the HVSR method. This method requires a measurement of estimate of shear wave velocity, which depends on the regolith sediment composition and density, for the conversion of measured resonance frequency to a depth to bedrock. Shear wave velocities were calculated for sediment in Shenandoah NP at locations where regolith thickness is known (e.g. at documented boreholes). The locations in this study were generally selected to characterize the depths to bedrock adjacent to streams monitored for coupled temperature and flow dynamics related to several ongoing USGS projects.

1D transient numerical simulations with a modified version of the SUTRA model (preliminary code) that accounts for variably-saturated freeze-thaw dynamics (e.g. McKenzie and Voss, 2013) to predict annual alluvial aquifer temperature dynamics using coupled fluid and heat transport physics. The model simulations were run with a modified version of SUTRA_ICE (unreleased) that accomadates a time-variable sinusiodal upper temperature boundary. This data release also includes the source code and Argus One GUI files used to build the models, though this proprietary software is not needed to run the models as described in the upper-level "readme" file.

1D transient numerical simulations with a modified version of the SUTRA model (preliminary code) that accounts for variably-saturated freeze-thaw dynamics (e.g. McKenzie and Voss, 2013) to predict annual alluvial aquifer temperature dynamics using coupled fluid and heat transport physics. The model simulations were run with a modified version of SUTRA_ICE (unreleased) that accomadates a time-variable sinusiodal upper temperature boundary. This data release also includes the source code and Argus One GUI files used to build the models, though this proprietary software is not needed to run the models as described in the upper-level "readme" file.

Using the horizontal-to-vertical spectral-ratio (HVSR) method, we inferred the depth to bedrock at the Slate River Floodplain, CO, USA. The point-scale passive seismic data were collected using Model TEP-3C Tromino seismometers over 20 min or less intervals with the instruments coupled directly to the floodplain ground surface at 42 non-flooded locations during June 2021. The ratio of horizontal-to-vertical Fourier spectra (HVSR), determined using Grilla software (MOHO, S.R.L.), along with the estimated sediment shear-wave velocity, was used to calculate the depth to the bedrock contact. This passive seismic dataset indicates that the deepest bedrock is 16 m below the surface, while the bedrock reaches the surface at the hillslope. This release contains the inferred bedrock depths based on likely shear wave velocities (Vs) intrinsic to the underlying sediment, ranging from 300 m/s to 400 m/s, listed in the processed_data subdirectory in the file 'SLAC_HVSR_June2021.csv.' The range of possible depth to bedrock interpretations is included for demonstration purposes only.

Data about the top and bottom altitude, depth from land surface and/or the thickness of three geologic units in Tennessee were converted into geospatial format for this USGS data release from previously published paper maps and converted into digital formats for use by the public. The three geologic units were the Chattanooga Shale of Mississippian-Devonian age (Moore and Horton, 1999), the Wells Creek Dolomite of middle Ordovician age (Smith, 1959), and the Knox Group of lower Ordovician age (Newcome, 1954). These geologic units represent important geologic horizons across Tennessee. Geologic structure maps provide important information and, in digital format, support investigative and modeling efforts pertaining to water and mineral resources. Prior to this work, the paper source maps used for this data release existed in limited quantities, mainly restricted to the Nashville, TN offices of the Tennessee Department of Environment and Conservation (TDEC) and United States Geological Survey (USGS). The work for this project included (1) scanning and georeferencing original paper maps to create georeferenced images (GRI), (2) digitizing well location points and contour lines, (3) populating well and contour attribute tables with data from maps and associated reports, and (4) when possible, interpolating raster surfaces for the three geologic units of top and bottom altitude, depth from land surface to the top and bottom surface, and thickness. All raster surfaces were aligned to a modified version of the National Hydrogeologic Grid (Clark and others, 2018) to support USGS Lower Mississippi Gulf Water Science Center efforts to create a statewide hydrogeologic framework. All horizontal coordinated data are projected to NAD 1983 USGS Contiguous USA Albers. The raster vertical coordinate information was referenced to the North American Vertical Datum of 1988 (NAVD 88). This data release includes GRIs, vector data of the wells and mapped contours of top, bottom, or thickness, raster data, and related metadata files for each three geologic units under the associated child item tab. Dataset types can be identified by the following naming convention: i_ = georeferenced map images (GRI) po_ = points c_ = contours and closed depressions f_= faults and other structural features p_ = extent polygon ra_ = altitude raster rd_ = depth from land surface raster rt_ = thickness raster The datasets included on this main landing page are as follows: project_metadata.xml – metadata file for general project information studyarea_ext.zip: p_chttshl_ext.shp - mapped extent of the Chattanooga Shale in Tennessee p_wllscr_ext.shp - mapped extent of the Wells Creek Dolomite in Tennessee p_knx_ext.shp - mapped extent of the Knox Group in Tennessee The datasets included on the child item pages are as follows: Chattanooga Shale: geospatial geologic structural datasets in Tennessee: chttshl_metadata.xml - metadata file chttshl_alldata.zip: GRI/ i_chttshl_btm.tif - structure contour map of the bottom of the Chattanooga Shale (Moore and Horton, 1999) i_chttshl_data.tif - map of data used to create structure and isopach maps (Moore and Horton, 1999) i_chttshl_thk.tif - thickness contour map for the Chattanooga Shale (Moore and Horton, 1999) polygons/ p_knx_ext.shp - study area extent for the Chattanooga Shale p_hohenwald.shp - polygon for extend of the Hohenwald Platform (Moore and Horton, 1999) - supplemental data rasters/ ra_chttshl_btm.tif - altitude raster for the bottom of the Chattanooga Shale ra_chttshl_tp.tif - altitude raster for the top of the Chattanooga Shale rd_chttshl_btm.tif - depth from land surface raster of the bottom of the Chattanooga Shale rd_chttshl_tp.tif - depth from land surface raster of the top of the Chattanooga Shale rt_chttshl.tif - thickness raster for the Chattanooga Shale vectors/ c_chttshl_btm.shp - structure contours for the bottom of the Chattanooga Shale c_chttshl_btm_modified.shp - modified structure contours for the bottom

Data about the top and bottom altitude, depth from land surface and/or the thickness of three geologic units in Tennessee were converted into geospatial format for this USGS data release from previously published paper maps and converted into digital formats for use by the public. The three geologic units were the Chattanooga Shale of Mississippian-Devonian age (Moore and Horton, 1999), the Wells Creek Dolomite of middle Ordovician age (Smith, 1959), and the Knox Group of lower Ordovician age (Newcome, 1954). These geologic units represent important geologic horizons across Tennessee. Geologic structure maps provide important information and, in digital format, support investigative and modeling efforts pertaining to water and mineral resources. Prior to this work, the paper source maps used for this data release existed in limited quantities, mainly restricted to the Nashville, TN offices of the Tennessee Department of Environment and Conservation (TDEC) and United States Geological Survey (USGS). The work for this project included (1) scanning and georeferencing original paper maps to create georeferenced images (GRI), (2) digitizing well location points and contour lines, (3) populating well and contour attribute tables with data from maps and associated reports, and (4) when possible, interpolating raster surfaces for the three geologic units of top and bottom altitude, depth from land surface to the top and bottom surface, and thickness. All raster surfaces were aligned to a modified version of the National Hydrogeologic Grid (Clark and others, 2018) to support USGS Lower Mississippi Gulf Water Science Center efforts to create a statewide hydrogeologic framework. All horizontal coordinated data are projected to NAD 1983 USGS Contiguous USA Albers. The raster vertical coordinate information was referenced to the North American Vertical Datum of 1988 (NAVD 88). This data release includes GRIs, vector data of the wells and mapped contours of top, bottom, or thickness, raster data, and related metadata files for each three geologic units under the associated child item tab. Dataset types can be identified by the following naming convention: i_ = georeferenced map images (GRI) po_ = points c_ = contours and closed depressions f_= faults and other structural features p_ = extent polygon ra_ = altitude raster rd_ = depth from land surface raster rt_ = thickness raster The datasets included on this main landing page are as follows: project_metadata.xml – metadata file for general project information studyarea_ext.zip: p_chttshl_ext.shp - mapped extent of the Chattanooga Shale in Tennessee p_wllscr_ext.shp - mapped extent of the Wells Creek Dolomite in Tennessee p_knx_ext.shp - mapped extent of the Knox Group in Tennessee The datasets included on the child item pages are as follows: Chattanooga Shale: geospatial geologic structural datasets in Tennessee: chttshl_metadata.xml - metadata file chttshl_alldata.zip: GRI/ i_chttshl_btm.tif - structure contour map of the bottom of the Chattanooga Shale (Moore and Horton, 1999) i_chttshl_data.tif - map of data used to create structure and isopach maps (Moore and Horton, 1999) i_chttshl_thk.tif - thickness contour map for the Chattanooga Shale (Moore and Horton, 1999) polygons/ p_knx_ext.shp - study area extent for the Chattanooga Shale p_hohenwald.shp - polygon for extend of the Hohenwald Platform (Moore and Horton, 1999) - supplemental data rasters/ ra_chttshl_btm.tif - altitude raster for the bottom of the Chattanooga Shale ra_chttshl_tp.tif - altitude raster for the top of the Chattanooga Shale rd_chttshl_btm.tif - depth from land surface raster of the bottom of the Chattanooga Shale rd_chttshl_tp.tif - depth from land surface raster of the top of the Chattanooga Shale rt_chttshl.tif - thickness raster for the Chattanooga Shale vectors/ c_chttshl_btm.shp - structure contours for the bottom of the Chattanooga Shale c_chttshl_btm_modified.shp - modified structure contours for the bottom