OFR 97-492: Norfolk 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.]

North Carolina
Subcontractors for the Savannah River Laboratory (SRL) collected at least 6,666 stream-sediment, 295 surface-water, and 5,778 ground-water samples within 100 counties from North Carolina as part of the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program. The sediment samples were collected during June - December 1976; July - August 1977; and April - May 1978, and water samples were collected during December 1976 - August 1977 and June - July 1978. Sample coverage included portions of the Beaufort, Charlotte, Chattanooga, Currituck Sound, Florence, Georgetown, Greensboro, Greenville, Johnson City, Knoxville, Manteo, Norfolk, Raleigh, Rocky Mount, Rome, Spartanburg, and Winston-Salem 1:250,000-scale quadrangles. (A total of 406 stream-sediment and 571 ground-water samples were collected within the Norfolk 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 6,597 sediments and 6,040 waters from North Carolina; this includes 405 sediment and 571 water samples from the Norfolk quadrangle. SRL also analyzed 20 sediment samples from Pasquotank County twice. The analytical and site location data for all North Carolina samples were released in the North and South Carolina Data Report [GJBX-102(82)].

SRL sent 4,677 sediment samples from North Carolina to an unnamed contract laboratory for "Supplemental Analyses." Supplemental analytical determinations for up to 23 elements were reported for 4,660 of these samples in the North and South Carolina Data Report [GJBX-102(82)]. The digital data file accompanying this report include Supplemental Analyses for 194 North Carolina sediment samples within the Norfolk quadrangle. (One of the Norfolk sediment samples in this report did not have any supplemental analysis data).

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 413 stream-sediment and 403 ground-water samples were collected within the Norfolk 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 411 sediment and 403 water samples from the Norfolk 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 includes Supplemental Analyses for 138 Virginia sediment samples within the Norfolk quadrangle.

SRL: Norfolk and Southern Eastville Quadrangles
SRL released a separate quadrangle report for the Norfolk and Southern Eastville (Currituck Sound) NTMS quadrangles. The abstract reports that 840 stream-sediment samples and 1,008 ground-water samples were collected but the report includes data for 843 stream-sediment and 1,008 ground-water samples. Of these, 839 stream-sediment and 971 ground-water samples were collected from the Norfolk quadrangle. SRL released the analytical data as the Norfolk and Southern Eastville Quadrangle GJBX-283(81) Preliminary Basic Data Report. Although these data are given on microfiche that accompanies the report, no digital data files were found for this reformatting effort. A cursory comparison of the [GJBX-283(81)] data suggests that there are some minor differences between this set of HSSR data and that found for corresponding samples in the Virginia and North Carolina State reports. The report often lists 'not detected' values for Dy and Yb in sediments that are missing in the State reports. Uranium values differ very slightly between the two reports. These variations appear to be due to differences in rounding versus truncation of reported values.

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
Because of the various laboratories and analytical methods used, some SRL samples may have been analyzed once, twice, or not at all. The following table summarizes the analysis of Norfolk quadrangle samples.

Combination of laboratories that analyzed samples for the Norfolk quadrangle.
Laboratory Analysis Sediments Waters
Only SRL 505 974
Only Supplemental Lab 1 0
Both SRL and Supplemental Labs 331 0
None 2 0
Total Samples 839 974
Total Data Records 839 974

The following is a list of all sediment and water sample types collected and reported for NURE studies in the Norfolk quadrangle.

Summary of Norfolk quadrangle sample types.
Sediment Sample Type Number of Samples Water Sample Type Number of Samples
Wet Streams 839 Wells 968
    Springs 6
Total Sediments 839 Total Waters 974

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

Sediment Samples

Water Samples



Discussion of the Reformatting Process for Norfolk Quadrangle

Sediment Records
The Norfolk quadrangle sediment data consist of reformatted records from the North Carolina portion of the North and South Carolina [GJBX-102(82)] Data Report and the Virginia portion 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 Norfolk quadrangle sediment data:

  1. In the State files, 20 sediment samples from Perquimans County, North Carolina were each represented by two records with different analytical data. The data tables in the Norfolk and Southern Eastville Quadrangle GJBX-283(81) Preliminary Basic Data Report identified one of each pair to be a second sample with a SRLID number containing the suffix S2 instead of the usual S1. This raises another problem. Normally, a suffix change on SRL sample numbers was reserved for different sediment size fractions. However, no indication of a different size fraction was noted for these 20 samples. Despite this potential problem, the SRLID value suffix was changed for each affected record and the change was noted in the REFORMAT comment field.
  2. 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.
  3. An unlikely sample collection date was found for one sample. This date was removed from the SAMPDAT field and the original SAMPDAT value with the most likely correct value was added as a comment to the REFORMAT field.
  4. An analysis of latitude-longitude site coordinates identified several stream-sediment samples that were missing coordinates, did not plot within expected state, county, or map boundaries, or had differing coordinates in corresponding records. To correct or confirm sample coordinates, the original field collection maps for Camden and Gates Counties, North Carolina were obtained and re-digitized. The newly re-digitized coordinates were added to the database and the coordinates from the original file(s) were recorded in the COORDPRB comment field. When the newly re-digitized coordinates were not significantly different, that confirmation of the site location was also noted in the COORDPRB comment field.
  5. 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.

Water Records
The Norfolk quadrangle water data consist of reformatted records from the North Carolina portion of the North and South Carolina [GJBX-102(82)] Data Report and the Virginia portion 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 Norfolk quadrangle water data:

  1. 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.
  2. An analysis of latitude-longitude site coordinates identified several ground-water samples that were missing coordinates, did not plot within expected state, county, or map boundaries, or had differing coordinates in corresponding records. To correct or confirm sample coordinates, the original field collection maps for Edgecombe and Gates Counties, North Carolina; and Brunswick County, Virginia were obtained and re-digitized. The newly re-digitized coordinates were added to the database and the coordinates from the original file(s) were recorded in the COORDPRB comment field. When the newly re-digitized coordinates were not significantly different, that confirmation of the site location was also noted in the COORDPRB comment field.
  3. The latitude and longitude coordinates for two ground-water samples collected within Nasemond County, Virginia were not found in the data during the reformatting process. The records for these 2 samples 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).

Norfolk Quadrangle Sediment Data - 839 records
Norfolk Quadrangle Water Data - 972 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 Norfolk quadrangle is complete and includes samples from Bertie, Camden, Chowan, Currituck, Edgecombe, Gates, Halifax, Hertford, Martin, Nash, Northampton, Pasquotank, Perquimans, and Warren Counties in North Carolina; and Brunswick, Dinwiddie, Greensville, Isle of Wright, Nasemond, South Hampton, Surrey, and Sussex Counties in Virginia. The laboratory and analytical methods used also may vary by county such that adjacent counties often have very different analytical coverages.

Two stream-sediment samples within Sussex County, Virginia were not analyzed by any of the various laboratories.



Other NURE Geochemical Data for the Norfolk Quadrangle

Geology and Mineral Resources Study
A report on the geology and mineral resources of the Florence, Beaufort, Rocky Mount, and Norfolk quadrangles was prepared for the Savannah River Laboratory [GJBX-197(82)]. No geochemical data accompany this report.

Characteristics of the Southeastern Piedmont
Bendix Field Engineering Corporation released a report that contains stream-sediment, hydrogeochemical, and aeromagnetic data for 16 contiguous NTMS quadrangles in the eastern United States [GJBX-40(83)]. This compilation report is limited in scope to features that have specific interest to the geoscience community. Included in the report are aeromagnetic and geochemical maps, and tectonic and igneous rock distribution maps. When used together, these maps show geochemical, tectonic, and magnetic features unique to many of the geologic and physiographic provinces in the region. This report primarily covers the Southeastern Piedmont region and includes the Athens, Augusta, Bluefield, Charlotte, Florence, Georgetown, Greensboro, Greenville, Knoxville, Norfolk, Raleigh, Richmond, Roanoke, Rocky Mount, Spartanburg and Winston-Salem 1:250,000-scale quadrangles. The color maps are in 35mm-slide format. No digital data files accompany this report.

North America and Africa Plutonic Rocks Special Study
The SRL in contract with the Department of Geology of the University of North Carolina conducted a special study to investigate the association of uranium deposits with granitic source or host rocks. The analytical results from 441 samples of 92 plutons were released in the North America and Africa Plutonic Rocks Special Study GJBX-221(82) report. See the North America and Africa Plutonic Rocks Special Study for the data and a more detailed description of this study. Plutons that were apparently sampled in the Norfolk quadrangle include the Castalia (4 samples) and Petersburg(5).



Norfolk Quadrangle NURE Bibliography



Links Within Open-File Report 97-492

Back to Virginia NURE data
Back to North Carolina 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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