OFR 97-492: Winnemucca Quadrangle NURE HSSR Study

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National Geochemical Database—Reformatted Data from the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) Program

By Steven M. Smith
Version 1.40 (2006)
Under Construction This page is currently being rewritten to the Version 1.41 format.

Brief History and Description of Data

[See History of NURE HSSR Program for a summary of the entire program.]

The Lawrence Livermore Laboratory (LLL) was responsible for the collection and analysis of NURE samples from the Winnemucca quadrangle. Contractors were hired to collect the reconnaissance samples. Between March of 1976 and August of 1978, a total of 1,081 sediment samples (1,019 reconnaissance samples, 56 site duplicate samples, and 6 analytical duplicate samples) and 215 water samples (210 reconnaissance samples and 5 analytical duplicate samples) were collected for the LLL Winnemucca Quadrangle NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) study. LLL crews resampled 13 sediment sites and 4 water sites as part of their quality assurance program during August - October of 1976. The corresponding reconnaissance sample number was cross referenced. All of these samples were analyzed by LLL for uranium and several other elements and the analytical data were released in the GJBX-89(78) report.

The following is a list of all sample types (including duplicates) collected in the Winnemucca quadrangle and included in the NEW-FORMAT NURE data files.

Summary of Winnemucca quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Wet Streams 254 Streams 129
Dry Streams 840 Wells 6
Springs 84
Total Sediments 1,094 Total Waters 219

These Winnemucca quadrangle samples were analyzed by one or more of the following methods:

Sediment Samples

Water Samples



Composition of the NEW-FORMAT NURE Data Files

The data in the NEW-FORMAT NURE data files consist of records from the LLL GJBX-89(78) report. The coordinate locations for quality-assurance samples were checked against the coordinates for the cross-referenced original sites and differences were noted in the REFORMAT comment field.

Unlike data from other laboratories, the original LLL sediment data files do not indicate when elemental concentrations fall below analytical determination limits. Other laboratories usually report these values as "less than the lower analytical determination limit" (represented by a negative number). These data were added to the NEW-FORMAT NURE data files based upon the approximate lower limits of detection given in Table 2 of the adjacent Millett quadrangle GJBX-39(79) report. (Note: The Winnemucca GJBX-89(78) report does not contain a table for lower limits of detection).

The original LLL files also contained numerical estimates of the absolute error associated with each elemental concentration. These data were not included in the NEW-FORMAT NURE data files but were placed into additional supplemental data files. The Absolute Error Extra Data Format is explained later in this document.



Download The Data

The NURE HSSR data are now available online in two databases: The sediment database (also includes data for soils and some rocks) at http://tin.er.usgs.gov/nure/sediment/ and the water database at http://tin.er.usgs.gov/nure/water/. From these two websites, NURE HSSR data can be selected, examined, summarized, and downloaded by political boundaries (State and County), by quadrangle (1:250,000-scale, 1:100,000-scale, and 1:63,360-scale for Alaska or 1:24,000-scale for the Lower 48 States), and by hydrologic unit (drainage region, subregion, river basin, or sub-basin). Selected data can be downloaded as a dBase file, a shapefile, an HTML table, or ASCII text (tab- or comma-delimited).

Winnemucca Quadrangle Sediment Data - 1,096 records
Winnemucca Quadrangle Water Data - 218 records
Under Construction LLL Error Estimates Data for Sediment Analyses - winnemsx.dbf.gz
Under Construction LLL Error Estimates Data for Water Analyses - winnemwx.dbf.gz



Notes for Data Users

Users of past versions of the Winnemucca quadrangle sediment database have had problems with LLL data because the fields were blank when the element concentration fell below the lower analytical determination limits. This absence of the lower end of the data population was responsible for skewing the data in statistical and contouring programs to levels that were higher than expected. As described above, the NEW-NURE FORMAT attempts to solve this problem by replacing those blanks with "less than" values based on reported lower determination limits.



Other NURE Geochemical Data for the Winnemucca Quadrangle

In 1982, the Bendix Field Engineering Corporation (BFEC) of Grand Junction, Colorado prepared a summary evaluation of the Winnemucca quadrangle [PGJ/F-129(82)]. For the BFEC study, samples of 227 rocks, 327 drill cuttings, and 122 stream waters were collected within the Winnemucca quadrangle to aid in identifying uranium occurrences. The rocks and drill cuttings were analyzed for uranium by fluorometry and for 29 other elements by emission spectrography. The water samples were analyzed for uranium oxide with a Scintrex Uranium Analyzer. These data were released only as microfiche appendices and accompany the summary report.



Winnemucca Quadrangle NURE Bibliography



LLL Estimates of Absolute Error Extra Data Format

Explanations are only included here for fields unique to these files. For the explanation of common fields consult the On-Line Manual for New-Format NURE HSSR Data Files. After each field name is a format code. A format code of (N) means that the field is formatted as an Numeric field.

U_DN_ERR (N)

A statistical estimate of measurement uncertainty associated with quantifying the corresponding uranium concentration determined by Delayed-Neutron Counting Analysis. (expressed as a percentage of the uranium concentration found in field U_DN_PPM for sediment data or U_DN_PPB for water data in the NEW-NURE FORMAT data files).

EL_ERR (N)

(Where EL represents different element symbols.) A numerical estimate of the uncertainties associated with quantifying the corresponding elemental concentration determined by Neutron Activation Analysis. (expressed in the same concentration units as the element concentration found in the NEW-NURE FORMAT data files).



Links Within Open-File Report 97-492

Back to Nevada NURE data
Frequently Asked Questions Concerning NURE HSSR Data
Home Page: USGS National Geochemical Database - NURE HSSR data



Page written by Andrew W. Holt and Steven M. Smith
Contact: Steven M. Smith (smsmith@usgs.gov)
Version 1.10: July 29, 1999
Version 1.20: August 07, 2000
Version 1.30: September 11, 2001
Version 1.40: January 13, 2006

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