Geochemistry of soils and other regoliths collected and analyzed by Hans Shacklette and colleagues from 1958 until about 1976.
Show in your GIS using OGC web services:
https://mrdata.usgs.gov/services/ussoils (WMS, version 1.3.0)
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Get the entire data set:
ussoils.zip (zipped shapefile 131k bytes)
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