The Department of Natural Resources, Division of Geology and Earth Resources, received a grant from the U.S. Geological Survey to sample Washington as part of the National Geochemical Survey (NGS). The sampling project is completed, and the results of the analysis are now available in the National Geochemical Survey Database.
The NGS is intended to produce a body of geochemical data for the U.S. based primarily on stream sediments, analyzed using a consistent set of methods. These data will compose a complete, national-scale geochemical coverage of the U.S. The goal of the NGS is to analyze at least one stream-sediment sample in every 289 sq. km area by a single set of analytical methods across the entire nation, with other solid sample media substituted where necessary. At the present time, the NGS includes data covering about 71 percent of the land area of the U.S., including samples in all 50 states. Only about 25 percent of Washington has been done.
The purpose of a national-scale geochemical database is to locate areas of the Earth's crust where mineralization processes have occurred. Many ore deposits have been found using geochemical methods. Data generated for geochemical exploration can also be used for many other purposes, including constructing geochemical maps, establishing geochemical baselines for use in environmental studies, and providing context for a wide variety of studies in the geological and environmental sciences, such as resolving controversies arising from questionable correlation of geologic units and studying the crustal evolution of the planet.