Hydrogeologic framework top-surface altitude rasters for the Virginia Eastern Shore

In support of a groundwater-flow model of the Virginia Eastern Shore, altitudes were determined for the tops of hydrogeologic surfaces, including incised paleochannel surfaces, that compose the framework within the model area. Rasters were generated from the altitude data for the tops of the surficial aquifer, upper confining unit, upper aquifer, middle confining unit, middle aquifer, lower confining unit, lower aquifer, Saint Marys confining unit, paleochannel upper aquifer, paleochannel confining unit, and paleochannel lower aquifer (McFarland and Beach, 2019; McFarland, 2019).

This data release includes the 11 rasters mentioned above for the Virginia Eastern Shore, in tiff format. Altitude contours from existing shapefiles in McFarland (2019) and Andreasen and others (2013) were the primary sources for unit top altitudes represented by the rasters. In the northern part of the study area, the surface altitude contours from Andreasen and others (2013) were used to supplement the contours from McFarland (2019). Topobathymetric data (Faunce and Rapp, 2020) were the source for development of the raster representing the top of the surficial aquifer.

References:
 
Faunce, K.E., and Rapp, J.L., 2020, Topobathymetric Digital Elevation Model (TBDEM) of the Eastern Shore Peninsula of Virginia and adjacent parts of Maryland with a horizontal resolution of 1 meter and vertical resolution of 1 centimeter: U.S. Geological Survey data release, https://doi.org/10.5066/P9F5CV1Y.

McFarland, E.R., 2019, Borehole hydrogeologic-unit top-surface altitudes, aquifer hydraulic properties,
and groundwater-sample chloride-concentration data from 1906 through 2016 for the Virginia Eastern Shore:
U.S. Geological Survey data release, https://doi.org/10.5066/P9MPE5SD.

McFarland, E.R., and Beach, T.A., 2019, Hydrogeologic framework of the Virginia Eastern Shore: U.S. Geological
Survey Scientific Investigations Report 2019–5093, 26 p., 13 pl., https://doi.org/10.3133/sir20195093.