OFR 97-492: Mesa Quadrangle NURE HSSR Study

  About USGS /  Science Topics /  Maps, Products & Publications /  Education / Publication: FAQ


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.]

Totals of 714 sediment and 365 water samples were collected in the Mesa quadrangle between February and May of 1979 as part of the Savannah River Laboratory (SRL) Mesa Quadrangle NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) study. These samples were analyzed by SRL for uranium and other elements (16 additional elements in sediments and 9 in waters) and the analytical data were released in the Mesa NURE HSSR quadrangle GJBX-216(80) report. The samples were then sent to other laboratories including Oak Ridge Gaseous Diffusion Plant (ORGDP) for "supplemental analyses", with results for 23 elements in sediments and 31 elements in waters. The supplemental analytical data were released by SRL in the Mesa quadrangle GJBX-81(80) supplemental data report.

In 1982, SRL released a summary report and data files for 50 quadrangles in the Western United States. This report, GJBX-132(82), contains both the SRL analytical data and the supplemental analytical data from the Mesa quadrangle but the concentration values often differ from those reported in the GJBX-216(80) and GJBX-81(80)quadrangle reports. The introduction section of the GJBX-132(82) summary report states:

"The data in the present report may not be identical to those reported previously. This is due to the use of different "scrub" procedures for the preparation of the data for release. The differences should be minor."

However, during the reformatting process several major differences were discovered between the two data sets for the water samples.

SRL analyses of light hydrocarbons (methane, ethane, propane, and butane) in ground waters were released in the GJBX-131(82) summary report for 44 western quadrangles and 3 eastern quadrangles within the United States. This report includes data for 289 of the Mesa quadrangle ground water samples.

Data for gold analyses of sediments by SRL neutron activation were released in the GJBX-135(82) summary report. The introduction of that report states:

"This report contains previously unreported neutron-activation analyses of gold in sediment samples determined at SRL. These data were not included in the standard SRL NURE data reports because the gold spectrum was not measured in the original analytical procedure and the report format was designed without the gold analyses being included. Gold analyses became available as the analytical procedure was refined, but the report format was not modified to incorporate these data."

Only those sediment samples that had detectable concentrations of gold by neutron activation analysis were given in the GJBX-135(82) report. Sediment samples with concentrations below detection limits were not reported and can only be ascertained by identifying which samples were actually analyzed by neutron activation at SRL.

The following is a list of sample types collected and reported for NURE studies in the Mesa quadrangle. The actual number of records in the NEW-FORMAT NURE data files may be greater because of the multiple records needed to preserve all the data.

Summary of Mesa quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Dry Streams 1 Wells 245
Soils 710 Springs 118
Talus 2 Other 2
Other (may include mine tailings) 1
Total Sediments 714 Total Waters 365

These Mesa 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 all of the above reports. In order to reduce the number of records, a decision was made to primarily use the data from the GJBX-132(82) western U.S. summary report. The rationale for choosing this data set was that (1) it represents a later compilation of the data and (2) it should be more consistent across quadrangle boundaries because of the common "scrubbing procedure." Every record was checked against the "equivalent" record in the earlier GJBX-216(80) quadrangle report and any major differences were noted in the REFORMAT comment field. These different but unused quadrangle report records were combined and saved as extra files which may be accessed below.

In the sediment data file, the SRL analyses and the supplemental analyses were combined into a single record for each sample. Unfortunately, in the water data file the SRL analyses and supplemental analyses could NOT be combined because of overlapping determinations for 5 elements. Each water sample may therefore have 2 separate records - one for the SRL analysis and one for the supplemental analysis.

The data reported in the GJBX-81(80) Supplemental Data Report included values for Th by an undocumented method. These extra Th values were NOT retained in the sediment data file TH_PPM field. Instead, the unused Th values were added as a comment in the REFORMAT comment field.

During the reformatting process, several problems were discovered between the water results reported in the GJBX-132(82) western U.S. summary report, and the GJBX-216(80) and GJBX-81(80)quadrangle reports.

  1. For some samples, the values given for U, Br, Cl, F, Mg, Na, and V in the western summary report are double the values given in the quadrangle report.
  2. Most of the Al and Dy values were missing in the western summary report. The missing values were NOT added to the water file from the quadrangle report.
  3. Some of the Br values were missing in the quadrangle report. The missing values were NOT added to the water file from the western summary report.

These problems could not be satisfactorily resolved during the reformatting process. Note: the unused data from the GJBX-216(80) and GJBX-81(80) quadrangle reports were saved as extra data files which may be accessed below.

Hydrocarbon data from the GJBX-131(82) report were added to fields in the appropriate ground water records and this addition was noted for each record in the REFORMAT comment field.

Gold concentrations from the GJBX-135(82) report were added to the appropriate sediment records. A value of -0.01 (<0.01 ppm Au) was added to all other sediment samples determined to have been analyzed by SRL neutron activation. This value was chosen because 0.01 is the lowest reported gold concentration in the entire report.

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).

Mesa Quadrangle Sediment Data - 715 records
Mesa Quadrangle Water Data - 728 records
Under Construction Unused set of quadrangle sediment records - mesa__sx.dbf.gz
Under Construction Unused set of quadrangle water records - mesa__wx.dbf.gz

Notes for Data Users

Many records contain analytical values with insignificant digits. Most data should only have 2 or 3 significant digits and differences after the second or third digit should be ignored.

Other NURE Geochemical Data for the Mesa Quadrangle

A summary evaluation report was prepared for the Mesa quadrangle by the Bendix Field Engineering Corporation of Grand Junction, Colorado [PGJ/F-032(82)]. Additional samples of 667 rocks, and 24 waters were collected in the quadrangle to "identify environments and delineate areas favorable for the occurrence of uranium deposits." The water samples and 287 of the rock samples were analyzed for uranium oxide by fluorometry, 605 of the rock samples were analyzed for up to 35 constituents, and 552 of the rock samples also underwent gamma spectrometry for eK, eU, and eTh. These data were released only as microfiche appendices and tables accompanying the summary report.

Mesa Quadrangle NURE Bibliography

Links Within Open-File Report 97-492

Back to Arizona 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

USA.gov logo