NGS Database Documentation.

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NGS Database Documentation.

The primary NGS database has a relational structure, containing many component tables. For the purposes of this online data release, the database has been restructured as a large flat file containing 77212 rows (samples) and 284 columns (data fields). To facilitate downloading and distribution of these data, the data fields have been divided into 15 categories, which may be viewed in detail here. The major categories are:

Categories containing sample attributes.
- Basic sample info: Critical data fields identifying the sample and dataset to which it belongs.
- Geographic information: Geographic coordinates and calculated geographic information.
- Sample attributes: Basic information about what a sample is and how it was collected.
- Sample attributes - detailed: Various secondary sample ID's and secondary information about the sample.
- Site attributes: Basic data about the nature of the sample collection site.
- Site attributes - detailed: Secondary information about the sample collection site.
- Analytical details: Information about analysis-of-variance samples, secondary lab ID's, and processing notes.
Categories containing analytical data.
- Analyses by ICP/Acid dissolution: Analytical data for ICP 40-element method.
- Analyses by ICP Partial Chem : Analytical data for ICP 10-element method.
- Analyses by Fusion ICP: Analytical data for ICP 16-element method.
- Analyses by AA: Analytical data for all atomic absorption methods
- Analyses by NAA: Analytical data for INAA and DN methods.
- Analyses by XRF: Analytical data for x-ray fluorescence method.
- Analyses for light elements: Analytical data for carbon and sulfur methods.
- Analyses by NURE program: Analytical data from the original NURE program.

These categories are used to select entire families of data fields for inclusion in or exclusion from downloaded datasets. Documentation for all 284 of the individual fields may be found here. Particularly important parts of this documentation may also be referenced below:

Geographic information in the NGS, and how it was derived.
Record numbers in the NGS.
Laboratory numbers used by all analytical facilities contributing to the NGS.
Sample names used by the many field collection teams contributing datasets to the NGS.
Analytical chemistry fields, and how they are structured in the database.
Sample media fields, describing what kinds of samples were analyzed for the NGS.
Analysis of variance fields, and how AOV samples are tracked in the database.

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://www-tin.er.usgs.gov/geochem/doc/dbdoc.htm
Maintained by Jeff Grossman
Last modified: 13:09:56 Wed 01 Oct 2008
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