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Mineral Resources On-Line Spatial Data

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As

Au, Pd, Pt

C, S

ICP40

ICP16

ICP10

Hg

NAA

Sb

Se

Te, Tl

W

XRF

NURE

Analytical Methods and Database Fields in the NGS

A limited number of analytical methods were used for samples in the NGS in order to provide the maximum level of internal consistency possible to the database.  Documentation on all of these methods is available via the links in the table below.  Four of these are considered to be "principal" methods in determining whether a particular area of the US is complete (see separate discussion on the Status of the NGS): the ICP 40-element acid-dissolution method, and atomic-absorption methods for As, Se, and Hg.  All other methods are "secondary" in that data were incorporated into the NGS when available, but were not required for a sample to be considered complete.

Each record in the NGS database contains analytical data. Data are grouped by analytical method, and structured as follows:

U.S. Department of the Interior, U.S. Geological Survey
This page is part of U.S. Geological Survey Open-File Report 2004-1001
URL: http://mrdata.usgs.gov/geochem/doc/analysis.htm
Maintained by Jeff Grossman
Last modified: 12:07:25 Tue 20 Dec 2016
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