OFR 97-492: Denver 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)

Brief History and Description of Data

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

LASL: South Park Waters Pilot Study
A Los Alamos Scientific Laboratory (LASL) pilot geochemical study collected 464 water samples from 149 locations in South Park, Colorado during August 1975. The objective of this study was to test the field sampling and analytical methodologies proposed for NURE Hydrogeochemical and Stream Sediment Reconnaissance projects in the Rocky Mountain states and Alaska. A total of 306 water samples from 98 locations were collected within the Denver quadrangle. These Denver quadrangle samples consisted of 225 waters from 71 streams; 69 waters from 23 springs; and 12 waters from 4 wells. All of the South Park samples were analyzed for uranium content and the data were released in the South Park Waters Pilot Study GJBX-35(76) report.

LASL: Denver and Greeley Quadrangles
Totals of 1,060 sediment and 1,264 water samples were collected from 1,612 locations in the Denver quadrangle during August and September 1976 as part of the LASL Denver and Greeley Quadrangles NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) study. The samples were analyzed for uranium content and the data were released in the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report.

LASL: Denver Quadrangle
These same Denver quadrangle samples were reanalyzed later by multielement methods for up to 43 additional elements and the data were released in the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report.

Summary Tables
The following is a list of sample types collected for NURE studies within the Denver quadrangle.

Summary of Denver quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Wet Streams 538 Streams 773
Dry Streams 314 Wells 501
Wet Springs 88 Springs 198
Wet Natural Ponds 54 Natural Ponds 19
Dry Natural Ponds 4 Artificial Ponds 79
Wet Artificial Ponds 37    
Dry Artificial Ponds 25    
Total Sediments 1,060 Total Waters 1,570

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

Sediment Samples

Water Samples
(including the South Park Pilot Study waters)



Discussion of the Reformatting Process for Denver Quadrangle

Sediment Records
The Denver quadrangle sediment data consist of records from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report combined with records from the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report. When combining sample records, site descriptive information and coordinates were compared for all corresponding records. The following problems were found and addressed during the comparison, combining, and reformatting stages for the Denver quadrangle sediment data:

  1. During the NURE sample collection phase, LASL sites and samples were initially assigned a 6-digit integer Identification Number (LASLID) starting with 000001. After 1977, most LASL sites were reassigned a new 1-letter+5-digit Identification Number starting with A00001. All LASL samples and the early LASL reports use the 6-digit integer LASLID. Most of the later reports only use the 1-letter+5-digit LASLID. Although both sets of numbers were usually assigned sequentially, they do not correspond one to one with each other: 100001 does not equal C00001, etc. Whenever possible, the 1-letter+5-digit LASL Identification Number was saved in the LASLID field. When the corresponding 6-digit site number could be determined from sample number translation key lists or other sources, this Identification Number was saved in the SITE field.
  2. The correlation of the two LASL Identification Numbers for samples in the Denver quadrangle was first solved by comparing records from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report with those from the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report. Later a LASL Identification Number translation key was found for the Denver quadrangle sediment samples and the values were confirmed. The 1-letter+5-digit LASL Identification Number was saved in the LASLID field and the corresponding 6-digit site number was manually added to the SITE field. Therefore, the LASLID field contains the Identification Number found in the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report. The SITE field contains the corresponding LASL Identification Number used to label the original field maps, field notes, and sample containers and reported in the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report.
  3. When combining corresponding records from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) and Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) reports, it was found that the reported concentrations of uranium were often slightly different. Rather than discarding one of the values in the combined records, the concentration of uranium (analyzed by delayed neutron activation analysis) from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report was added to the extra uranium field (U_XX_PPM).
  4. Unlikely sample collection dates were found for four samples. These dates were removed from the SAMPDAT field. For each record, the original SAMPDAT value and the most likely correct value was added as a comment to the REFORMAT field.
  5. Two sediment sample records contained values for the well pump type(WELLPUMP) and well diameter(WELLDIAM). These parameters were not normally recorded for sediment sample records. The values were removed from each record and added as a comment to the corresponding REFORMAT field.
  6. Two sediment sample records contained an invalid value in the relief (RELIEF) or rock type (ROCKTYP) fields. These values were likely miscoded or entered incorrectly. The correct values were not found. These values were removed from the respective fields and added as a comment to the REFORMAT field for each affected record.
  7. One wet stream-sediment sample has a longitude of exactly 106°W, the dividing line between the Denver quadrangle and the Leadville quadrangle. This coordinate value was not changed but a comment was added to the COORDPRB field.

Water Records
The Denver quadrangle water data records from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report combined with records from the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) reports plus records from the South Park Waters Pilot Study GJBX-35(76) report. When combining sample records, site descriptive information and coordinates were compared for all corresponding records. The following problems were found and addressed during the comparison, combining, and reformatting stages for the Denver quadrangle water data:

  1. The correlation of the two LASL Identification Numbers for samples in the Denver quadrangle was first solved by comparing records from the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report with those from the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report. Later a LASL Identification Number translation key was found for the Denver quadrangle water samples and the values were confirmed. The 1-letter+5-digit LASL Identification Number was saved in the LASLID field and the corresponding 6-digit site number was manually added to the SITE field. Therefore, the LASLID field contains the Identification Number found in the Denver Quadrangle NURE Multielement HSSR study GJBX-263(81) report. The SITE field contains the corresponding LASL Identification Number used to label the original field maps, field notes, and sample containers and reported in the Denver and Greeley Quadrangles NURE Uranium HSSR study GJBX-60(78) report.
  2. No LASL Identification Number translation key was found for the South Park Waters Pilot Study samples. The 6-digit LASL Identification Number found in LASLID was also added to the SITE field. Therefore, the value found in the LASLID and SITE fields is same LASL Identification Number used to label the original field maps, field notes, and sample containers as well as the value published in South Park Waters Pilot Study GJBX-35(76) report.
  3. Unlikely sample collection dates were found for six samples. These dates were removed from the SAMPDAT field. For each record, the original SAMPDAT value and the most likely correct value was added as a comment to the REFORMAT field.
  4. Four water sample records contained an invalid value in the relief (RELIEF), rock type (ROCKTYP), or vegetation density (VEGDENS) fields. These values were likely miscoded or entered incorrectly. The correct values were not found. These values were removed from the respective fields and added as a comment to the REFORMAT field for each affected record.
  5. Two separate spring-water samples from the Denver quadrangle HSSR study have the same latitude-longitude coordinates. It is unclear whether this represents a pair of samples collected at the same site or samples collected at separate sites so close together that the coordinate precision was insufficient to distinguish.
  6. 306 water samples from the Denver portion of the South Park Waters Pilot Study share the same latitude-longitude coordinates with up to six other samples (98 distinct coordinate sites). These represent multiple samples collected by slightly varying methods at the same sites.
  7. One stream-water sample has a longitude of exactly 106°W, the dividing line between the Denver quadrangle and the Leadville quadrangle. This coordinate value was not changed but a comment was added to the COORDPRB field.


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 web sites, 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).

Denver Quadrangle Sediment Data - 1,060 records
Denver Quadrangle Water Data - 1,570 records



Notes for Data Users

The water samples from the South Park Pilot Study were collected by 4 different methods, with respect to filtering and acidification. (See the SAMPTYP coding explanation in the On-Line Manual for USGS-Reformatted NURE HSSR Data Files for descriptions of different Sample Types). Analytical data may not be directly comparable for water samples collected by different methods.



Other NURE Geochemical Data for the Denver Quadrangle

Denver Quadrangle NURE Summary
A summary evaluation report was prepared for the Denver quadrangle by the U.S. Geological Survey [PGJ/F-078(82)]. An additional 301 stream-sediment, 161 ground-water, 46 stream-water and 485 rock samples were collected from all parts of the quadrangle except for the northern extension of the Buffalo Gulch area. The samples were analyzed for uranium as well as 44 other elements. The multielement analytical data were released only as appendices on microfiche accompanying the summary report.



Denver Quadrangle NURE Bibliography



Links Within Open-File Report 97-492

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



Page written by 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 1.41: February 23, 2006

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