OFR 97-492: Dixon Entrance Quadrangle NURE HSSR Study
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[See History of NURE HSSR Program for a summary of the entire program.]
During August of 1978 the Los Alamos Scientific Laboratory (LASL) collected samples for the NURE Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) study of the Dixon Entrance quadrangle and the Prince Rupert D-6 quadrangle. Standard LASL sampling procedure called for the collection of samples from the center of flowing streams. Sediment samples were to be sieved to collect the <100 mesh fraction and water samples were to be acidified. Since many streams in Alaska are fast flowing and deep, LASL was concerned that field personnel would be unable to sample the center of streams and that sediments collected from stream centers would contain insufficient <100 mesh material to analyze. For this study, LASL set out to examine the variation in elemental concentrations due to different sample treatments. This was done to determine if alternate sample treatments could substitute for the standard sampling methodology. Sampling was conducted at 203 sites. Each sediment sample was sieved into as many as 5 fractions for analysis to determine the variation of elemental concentrations due to grain size. Variation, due to sampling different locations within a stream, was examined by collecting from both the stream center and from the stream bank at 24 sediment sample sites. To determine the effects of sample treatment on elemental concentrations in waters, 2 samples were collected from each water sampling site. One water sample was filtered and acidified, and one was only acidified. In all, 950 sediment samples and 404 water samples were collected from the 203 sites sampled. A total of 899 sediment samples and 390 water samples from 196 locations were collected from the Dixon Entrance quadrangle. All samples were analyzed by LASL for uranium and the sediment samples were analyzed for up to 42 additional elements. The analytical results and the evaluation of variation due to sample treatments were compiled and published by LASL in the GJBX-257(80) report.
The following is a list of NURE sample types collected for these studies in the Dixon Entrance quadrangle.
| Sediment Sample Type | Number of Samples | Water Sample Type | Number of Samples |
|---|---|---|---|
| Wet Streams (<40 mesh) | 86 | Streams (acidified) | 88 |
| Wet Streams (<80 mesh) | 84 | Streams (acidified and filtered) | 88 |
| Wet Streams (<100 mesh) | 76 | Lakes (acidified) | 104 |
| Wet Streams (<170 mesh) | 64 | Lakes (acidified and filtered) | 104 |
| Wet Streams (<230 mesh) | 53 | Springs (acidified) | 3 |
| Dry Streams (<40 mesh) | 1 | Springs (acidified and filtered) | 3 |
| Dry Streams (<80 mesh) | 1 | ||
| Dry Streams (<100 mesh) | 1 | ||
| Dry Streams (<170 mesh) | 1 | ||
| Dry Streams (<230 mesh) | 1 | ||
| Stream Bank (<40 mesh) | 19 | ||
| Stream Bank (<80 mesh) | 19 | ||
| Stream Bank (<100 mesh) | 18 | ||
| Stream Bank (<170 mesh) | 16 | ||
| Stream Bank (<230 mesh) | 14 | ||
| Wet Lakes (<40 mesh) | 104 | ||
| Wet Lakes (<80 mesh) | 103 | ||
| Wet Lakes (<100 mesh) | 91 | ||
| Wet Lakes (<170 mesh) | 77 | ||
| Wet Lakes (<230 mesh) | 60 | ||
| Wet Springs (<40 mesh) | 2 | ||
| Wet Springs (<80 mesh) | 2 | ||
| Wet Springs (<100 mesh) | 2 | ||
| Wet Springs (<170 mesh) | 2 | ||
| Wet Springs (<230 mesh) | 2 | ||
| Total Sediments | 899 | Total Waters | 390 |
These Dixon Entrance quadrangle samples were analyzed by one or more of the following methods:
Sediment Samples
Water Samples
The data in the NEW-FORMAT NURE data files consist of 899 reformatted sediment records and 390 reformatted water records from the GJBX-257(80) LASL Dixon Entrance/Prince Rupert D-6 report. Any changes in the data or problems found are noted in the REFORMAT comment field.
In the Dixon Entrance/Prince Rupert D-6 study [GJBX-257(80)], LASL assigned new SAMPTYP codes to each of the different sediment sieve fractions. Although these SAMPTYP codes were unique within this study, they overlapped SAMPTYP codes defined differently in other LASL NURE special studies. This overlap of SAMPTYP codes was resolved by reassigning the Dixon Entrance/Prince Rupert D-6 SAMPTYP codes, as defined in Appendix II-C of the GJBX-257(80) report, to equivalent SAMPTYP codes used elsewhere. When no equivalent code was available, the SAMPTYP was reassigned to a new code value not found in any other NURE study. Records where the SAMPTYP was reassigned are noted in the REFORMAT comment field. The description of the SAMPTYP codes used in the New-Format NURE data files can be found in the On-Line Manual for New-Format NURE HSSR Data Files.
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).
Dixon Entrance Quadrangle Sediment Data - 899 records
Dixon Entrance Quadrangle Water Data - 390 records
In other LASL Alaska quadrangle HSSR studies, water samples are reported to have been acidified with nitric acid but NOT filtered in the field. In the Dixon Entrance/Prince Rupert D-6 study water samples were reported to have been acidified but NOT filtered in the field, OR acidified AND filtered in the field. These different sample treatments can be identified using the SAMPTYP code and the corresponding definition in the On-Line Manual for New-Format NURE HSSR Data Files.
The ORGDP fluorometric procedure for uranium required each water sample to be centrifuged before taking an aliquot for analysis. It is not clear whether water samples analyzed by emission spectrometry were also centrifuged prior to analysis.
A summary evaluation report was prepared for the Dixon Entrance quadrangle by the Bendix Field Engineering Corporation of Grand Junction, Colorado [PGJ/F-047(82)]. Additional samples of 326 organic muck and soils, 93 rocks, 131 waters, and 56 lodgepole pine twigs were collected in the Alaska portion of the quadrangle to "identify and delineate environments favorable for uranium deposits." All of the muck and soil, rock, and lodgepole pine twig samples were analyzed for uranium oxide by fluorometry. Water samples were analyzed for uranium oxide using a Scintrex UA-3 uranium analyzer. All of the muck and soil samples were analyzed for organic carbon, and 172 were analyzed for up to 30 elements by semi-quantitative emission spectrography. Of the rocks, 89 were analyzed for eK, eU, and eTh by gamma spectrometry, and 34 were analyzed for up to 30 elements by semi-quantitative emission spectrography. Loss on ignition was measured for the lodgepole pine twigs. These data were released only as microfiche appendices accompanying the summary report.
LASL compiled all of the regional HSSR data from Alaskan NURE studies and produced a report [GJBX-32(83] that graphically displays the distribution of selected elements for most of the State. No additional geochemical data were released with this report.
Back to Alaska 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 1.20: August 07, 2000
Version 1.30: September 11, 2001
Version 1.40: January 13, 2006
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