Abstract:
The National Geochemical Data Base (NGDB)
http://minerals.cr.usgs.gov/projects/geochem_database/index.html The NGDB consists of 1) the original RASS and PLUTO data from the USGS labs,
which are now stored in a common format under the ORACLE relational database
management system; 2) the NURE data, which have been reformatted and reside
currently on the following web site:
... http://pubs.usgs.gov/of/1997/ofr-97-0492/
where downloads may be made on the basis of 1:250000-scale quadrangles; and 3)
the newly generated data (approximately 1996 - present) which reside on the
Laboratory Information Management System. The enhancements to the NGDB will
enable both USGS scientists and external customers to more easily extract
immediately useable data on a national, regional, and local scale to help
establish a baseline for the abundance and spatial distribution of chemical
elements in the Earth's surficial materials.
The National Geochemical Data Base (NGDB) contains more than two million data
records for samples of stream sediment, soil, rock, water, panned concentrate,
drill core, and vegetation collected during geochemical surveys conducted by
the U.S. Geological Survey (USGS) and other Federal Government agencies. The
data are from samples collected in the United States and foreign countries.
The NGDB includes data from the U.S. Geological Survey's National Mineral
Resource Assessment Program (NMRAP) and the Department of Energy's National
Uranium Resourse Evaluation Hydrogeo-chemical and Stream Sediment
Reconnaissance (NURE HSSR) program. Data from the Rock Analysis Storage System
(RASS) are also included.
Samples collected by USGS scientists were subjected to a variety of analytical
techniques depending on the research project being conducted. Some of the
methods applied were emission spectroscopy, neutron activation, x-ray emission,
atomic adsorption, and several wet chemical and other instrumental methods.
Further, most of the samples from which the NGDB was generated are held in
archival storage and are available for further analysis.
This data set includes the location name, latitude/longitude, rock name,
formation, geologic age, material class, sample source, sample type, and
chemical analyses information on rocks, soils, sediments, minerals, and plants.
The part of the NGDB containing the NURE HSSR data for the conterminous United
States has been published as a CD-ROM as USGS Digital Data Series DDS-18-A and
18-B. Data may be searched and retrieved by sample type, 1 X 2 quadrangle
name, latitude and longitude, element concentration range, or any combination
of these criteria. CD-ROMs are being developed for additional parts of the
NGDB.
Other data in the NGDB are available by writing the Data Center Contact above. 
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