National Geochemical Database: Sediment

Online link https://mrdata.usgs.gov/ngdb/sediment/
Description Geochemical analysis of sediment samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are of stream sediment in the continental US and Alaska.
Originators U.S. Geological Survey
Metadata Questions and answers
Schematic map showing sample density in the conterminous US
Schematic map showing sample density in the conterminous US