OFR 97-492: Chincoteague 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.]

Virginia
Subcontractors for the Savannah River Laboratory (SRL) collected at least 5,667 stream-sediment, 2,598 surface-water, and 4,834 ground-water samples within 96 counties from Virginia as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. The sediment samples were collected during July - October 1976; August - September 1977; and April - November 1978, and water samples were collected during December 1976 - September 1977; April - October 1978; and June - August 1979. Sample coverage included portions of the Baltimore, Bluefield, Charlottesville, Chincoteague, Cumberland, Currituck Sound, Greensboro, Jenkins, Johnson City, Norfolk, Richmond, Roanoke, Salisbury, Washington, and Winston-Salem 1:250,000-scale quadrangles. (A total of 63 stream-sediment and 95 ground-water samples were collected within the Chincoteague quadrangle.) These samples were sent to SRL for analysis of uranium and additional elements (16 in sediments and 9 in waters). SRL was able to analyze 5,522 sediments and 7,416 waters from Virginia; this includes 63 sediment and 94 water samples from the Chincoteague quadrangle. The analytical and site location data for all Virginia samples were released in the Delaware, Maryland, Virginia, and West Virginia Data Report [GJBX-103(82)].

SRL sent 2,719 sediment samples from Virginia to an unnamed contract laboratory for "Supplemental Analyses." Supplemental analytical determinations for up to 23 elements were reported for 2,711 of these samples in the Delaware, Maryland, Virginia, and West Virginia Data Report [GJBX-103(82)]. The digital data file accompanying this report does not include Supplemental Analyses for any Virginia sediment samples within the Chincoteague quadrangle.

Maryland
Subcontractors for the Savannah River Laboratory (SRL) collected at least 1,322 stream-sediment, 837 surface-water, and 1,188 ground-water samples within 23 counties from Maryland as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. The sediment samples were collected during May - August 1978, and water samples were collected during May - June 1977; December 1977; and July - October 1978. Sample coverage included portions of the Baltimore, Chincoteague, Cumberland, Salisbury, Washington, and Wilmington 1:250,000-scale quadrangles. (A total of 2 stream-sediment and 2 ground-water samples were collected within the Chincoteague quadrangle.) These samples were sent to SRL for analysis of uranium and additional elements (16 in sediments and 9 in waters). SRL was able to analyze 1,286 sediments and 2,023 waters from Maryland; this includes 2 sediment and 2 water samples from the Chincoteague quadrangle. The analytical and site location data for all Maryland samples were released in the Delaware, Maryland, Virginia, and West Virginia Data Report [GJBX-103(82)].

SRL: Richmond and Northern Eastville Quadrangles
SRL released a separate quadrangle report for the Richmond and Northern Eastville (Chincoteague) NTMS quadrangles, which includes data for 673 stream-sediment and 840 ground-water samples (a total of 63 stream-sediment and 94 ground-water samples from Chincoteague). SRL released the analytical data as the Richmond and Northern Eastville Quadrangle GJBX-18(81) Preliminary Basic Data Report. The site coding information for this data set is summarized within the text of this report. However, these separate quadrangle data for the Richmond and Chincoteague quadrangles were not found in digital format and are not included in the Chincoteague digital data file presented here. The hard copy of this preliminary data is available in the [GJBX-18(81)] data release. A preliminary comparison of the [GJBX-18(81)] data suggests that, there are some differences between this set of HSSR data and that found for corresponding samples in the Virginia and Maryland State reports. One minor difference is that analytical data values found in the digital state files are slightly different from the hard copy tables. These variations are apparently due only to differences in rounding versus truncation of reported values or to differences in the number of recorded significant digits.

Gold Analyses
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.

Summary Tables
The following is a list of all sample types collected and reported for NURE studies in the Chincoteague quadrangle.

Summary of Chincoteague quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Wet Streams 65 Wells 97
Total Sediments 65 Total Waters 97

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

Sediment Samples

Water Samples



Discussion of the Reformatting Process for Chincoteague Quadrangle

Sediment Records
The Chincoteague quadrangle sediment data consist of reformatted records from the Maryland and Virginia portions of the Delaware, Maryland, Virginia, and West Virginia [GJBX-103(82)] Data Report. The following problems were found and addressed during the comparison and reformatting stages for the Chincoteague quadrangle sediment data:

  1. During reformatting, contamination codes for "residential" and "recreation" were found to be missing from each State's CONTAMC field. The presence of one of these two codes was indicated only by a "." (period). The missing codes were assigned a value of "unknown" in the CONTAMC field within the final sediment data file.
  2. 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 ppm is the lowest reported gold concentration in the entire report.

Water Records
The Chincoteague quadrangle water data consist of reformatted records from the Maryland and Virginia portions of the Delaware, Maryland, Virginia, and West Virginia [GJBX-103(82)] Data Report>]. The following problems were found and addressed during the comparison and reformatting stages for the Salisbury quadrangle water data:

  1. The latitude and longitude coordinates for one water sample collected within Northampton County, Virginia was not found in the data during the reformatting process. This record cannot be retrieved on a geographical basis.


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).

Eastville Quadrangle Sediment Data (Chincoteague and Currituck Sound quadrangles) - 69 records
Eastville Quadrangle Water Data (Chincoteague and Currituck Sound quadrangles) - 123 records



Notes for Data Users

In the eastern United States, SRL collected samples primarily by county. Often, not all counties within a quadrangle were completely sampled. Sample coverage in the Chincoteague quadrangle is complete and includes samples from Somerset County in Maryland; and Accomack and Northampton Counties in Virginia. The laboratory and analytical methods used also may vary by county such that adjacent counties often have very different analytical coverage.

One well water sample within the Salisbury quadrangle from Accomack County, Virginia was not analyzed by any of the various laboratories.



Other NURE Geochemical Data for the Chincoteague Quadrangle

None found.



Chincoteague Quadrangle NURE Bibliography



Links Within Open-File Report 97-492

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



Page written by Bryan G. Moravec and Steven M. Smith.
Contact: Steven M. Smith (smsmith@usgs.gov)
Version 1.30: September 11, 2001
Version 1.41: February 23, 2006

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