OFR 97-492: Millett Quadrangle NURE HSSR Study
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This page is currently being rewritten to the Version 1.41 format.
[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 Millett quadrangle. Contractors were hired to collect the reconnaissance samples. University of Nevada collected ground water samples and Bendix Field Engineering Corp. collected sediment and surface water samples. Between August of 1976 and October of 1977, a total of 1,408 sediment samples (1,319 reconnaissance samples, 20 site duplicate samples, and 69 analytical duplicate samples), 2 rock samples, and 366 water samples (326 reconnaissance samples and 40 site duplicate samples) were collected for the LLL Millett Quadrangle NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) study. LLL crews resampled 3 sediment sites (3 samples) as part of their quality assurance program during September 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-39(79) report.
The following is a list of all sample types (including duplicates) collected in the Millett quadrangle and included in the NEW-FORMAT NURE data files.
| Sediment Sample Type | Number of Samples | Water Sample Type | Number of Samples |
|---|---|---|---|
| Wet Streams | 378 | Streams | 122 |
| Dry Streams | 1,032 | Wells | 46 |
| Wet Lakes or Reservoirs | 1 | Springs | 198 |
| Rocks | 2 | ||
| Total Sediments | 1,413 | Total Waters | 366 |
These Millett quadrangle samples were analyzed by one or more of the following methods:
Rock and Sediment Samples
Water Samples
The data in the NEW-FORMAT NURE data files consist of records from the LLL GJBX-39(79) 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.
In the sediment data file, coordinates place 3 samples in Ely quadrangle, 2 in Winnemucca quadrangle, and 1 in Elko quadrangle - this may or may not be an error. Also since the rock samples were treated by the same analytical methods as the sediments, the data for these 2 samples are included in the sediment data file.
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 GJBX-39(79) report.
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. Note that in the supplemental water file, the values in the U_DN_ERR field may differ slightly from published values in the second decimal place.
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).
Millett Quadrangle Sediment Data - 1,407 records
Millett Quadrangle Water Data - 366 records
LLL Error Estimates Data for Sediment Analyses - milletsx.dbf.gz
LLL Error Estimates Data for Water Analyses - milletwx.dbf.gz
Users of past versions of the Millett 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.
The Bendix Field Engineering Corporation of Grand Junction, Colorado prepared a summary evaluation of the Millett quadrangle [PGJ/F-138(82)]. An additional 489 rock, 240 water, and 24 sediment samples were collected "in order to evaluate the uranium resource potential of the Millett quadrangle." The rock and sediment samples were analyzed for uranium and 29 other elements. In addition, 30 were analyzed in the field and 89 were analyzed in the lab for eK, eU, and eTh, and 58 were analyzed for major element oxides and for Be, F, Hg, and Mo. The water samples were analyzed for uranium oxide. These data were released only as microfiche appendices that accompany the summary report.
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.
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).
(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).
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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