The U.S. Geological Survey has released the Geochemical and Mineralogical Maps for Soils in the Conterminous United States (Open-File Report 2014-1082).
The maps provide a visual representation of the national-scale geochemical, and mineralogical variation in soils. In 2007, the U.S. Geological Survey initiated a low-density (1 site per 1,600 square kilometers, 4,857 total sites) survey of soils of the conterminous United States. Three samples were collected at each site from the surface down to approximately 1 meter. In total, more than 14,400 soil samples were analyzed for 45 elements and 9,575 samples were analyzed for major minerals. The maps released today were created using datasets from the survey.
The datasets, which were released in October 2013 by USGS, provide a baseline for the abundance and spatial distribution of chemical elements and minerals against which future changes may be recognized and quantified.
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