Mineral Resources On-Line Spatial Data
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Boerngen, Josephine G., and Shacklette, Hansford T., 1981, Chemical analyses of soils and other surficial materials of the conterminous United States: U.S. Geological Survey Open-File Report 81-197, U.S. Geological Survey, Denver, CO.
This is a Point data set. It contains the following vector data types (SDTS terminology):
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 1 minute. Longitudes are given to the nearest 1 minute. Latitude and longitude values are specified in Decimal degrees.
Value | Definition |
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GCxxxxxx | Field number |
Range of values | |
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Minimum: | GC000250 |
Maximum: | GC280550 |
Range of values | |
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Units: | Degrees, minutes, seconds. |
Range of values | |
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Units: | Degrees, minutes, seconds. |
Value | Definition |
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XX | 2-letter state abbreviation |
Range of values | |
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Minimum: | 25.8333 |
Maximum: | 44.7000 |
Units: | Decimal degrees. |
Range of values | |
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Minimum: | 67.2833 |
Maximum: | 124.4000 |
Units: | Decimal degrees. |
Value | Definition |
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MM/YY | month (MM) and year (YY) |
Range of values | |
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Minimum: | 0.07 |
Maximum: | >10 |
Units: | Per cent |
Range of values | |
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Minimum: | <0.10 |
Maximum: | 97 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <20 |
Maximum: | 300 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | 10 |
Maximum: | 5,000 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <1 |
Maximum: | 15 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <0.50 |
Maximum: | 10.8 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | 0.06 |
Maximum: | 37 |
Units: | Per cent |
Range of values | |
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Minimum: | 0.01 |
Maximum: | 32 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <150 |
Maximum: | 300 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <3 |
Maximum: | 70 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | 1 |
Maximum: | 2,000 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <1 |
Maximum: | 700 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.001 |
Maximum: | 0.37 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | 0.01 |
Maximum: | >10 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <5 |
Maximum: | 70 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.1 |
Maximum: | 2,500 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.01 |
Maximum: | 4.6 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.5 |
Maximum: | 9.6 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | 0.005 |
Maximum: | 6.3 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <30 |
Maximum: | 200 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <5 |
Maximum: | 140 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | 0.005 |
Maximum: | >10 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <2 |
Maximum: | 7,000 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <3 |
Maximum: | 15 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.05 |
Maximum: | 10 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <10 |
Maximum: | 100 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <70 |
Maximum: | 300 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <5 |
Maximum: | 700 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <0.002 |
Maximum: | 0.68 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <10 |
Maximum: | 700 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <20 |
Maximum: | 210 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <0.08 |
Maximum: | 4.78 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <1 |
Maximum: | 8.8 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <5 |
Maximum: | 50 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | <0.1 |
Maximum: | 4.3 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | 1.69 |
Maximum: | 44.9 |
Units: | Per cent |
Range of values | |
---|---|
Minimum: | <0.1 |
Maximum: | 10.2 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <5 |
Maximum: | 3,000 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | 0.007 |
Maximum: | 2.0 |
Units: | Per cent |
Range of values | |
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Minimum: | 2.15 |
Maximum: | 30.8 |
Units: | Parts per million (PPM) |
Range of values | |
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Minimum: | 0.29 |
Maximum: | 10.7 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <7 |
Maximum: | 500 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <10 |
Maximum: | 200 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <1 |
Maximum: | 50 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <5 |
Maximum: | 2,900 |
Units: | Parts per million (PPM) |
Range of values | |
---|---|
Minimum: | <20 |
Maximum: | 2,000 |
Units: | Parts per million (PPM) |
303-236-1849 (voice)
303-236-3200 (FAX)
dsmith@usgs.gov
These data provide an ultra-low-density geochemical baseline for soils and other surficial materials in the conterminous United States. The data set contains 1,323 samples for a sampling density of approximately 1 sample per 6,000 square kilometers. The data set is currently the only national geochemical data set collected and analyzed according to standardized protocols. The data are most appropriately used to provide information on background concentrations of elements in soil. The major drawback with the data set is its extremely low number of samples for the entire conterminous US.
The soil samples were chemically analyzed by a variety of techniques over a period of time from the mid-1960's to the late 1970's. Details of the methods are given in the references listed in USGS Open-File Report 81-197 and USGS Professional Paper 1270.
In summary, the methods used were:
1) Emission spectrography (Myers and others, 1961; Neiman, 1976) for Al, Ba, Be, B, Ca, Ce, Cr, Co, Cu, Ga, Fe, La, Pb, Mg, Mn, Mo, Nd, Ni, Nb, P, K, Sc, Na, Sr, Ti, V, Yb, Y, Zn, and Zr;
2) EDTA titration for Ca;
3) colorimetric methods for P and Zn (Ward and others, 1963);
4) flame photometry for K (Ward and others, 1963);
5) flame atomic absorption (Huffman and Dinnin, 1976) for Hg, Li, Mg, Na, Rb, and Zn;
6) flameless atomic absorption for Hg (Vaughn, 1967);
7) X-ray fluorescence spectrometry (Wahlberg, 1976) for Ca, Ge, Fe, K, Se, Ag, S, and Ti;
8) Combustion (Huffman and Dinnin, 1976) for total carbon; and neutron activation (Millard, 1975, 1976) for U and Th.
The accuracy varies with the analytical methodology and with the concentration of the element being analyzed. A small portion of the database contains qualified data. The types of qualifiers in this data set are:
"N", meaning that the element was not detected at concentrations above the detection limit-this is shown in the data set as, for example, 5.000N meaning that the element was not detected at a concentration of 5 concentration units (ppm or %), the detection limit of the technique.
"L", meaning that the element was detected by the technique, but at a level below the detection limit-this is shown in the data set as, for example, 1.000L meaning that the element was detected by the instrument, but at a level that could not be quantified at or above the detection limit, 1 concentration unit.
"B", meaning that there is no data for that particular element in a given sample-this is shown in the data set as .0000B.
"G", meaning that the element was measured at a concentration greater than the upper determination limit for the technique-this is shown in the data set as, for example, 10.0000G, meaning that the element was measured at a concentration greater than 10 concentration units.
Sample locations were determined from USGS topographic maps of various scales. The sites are estimated to be accurate to the nearest minute of latitude and longitude.
Where chemical data is lacking for a given element in a given sample, ".0000B" is shown as the concentration value. Virtually every element in the data set has some samples in which the element was not analyzed. This may have been a conscious decision on the part of the investigators or it may have been the result of insufficient sample to complete all the analytical procedures. This lack of data is most common for the elements Br, C, Ge, I, Rb, S, Sb, Si, Sn, Th, and U.
USGS Open-File Report 81-197 gives analytical values for 46 elements analyzed by a variety of methods. For some elements, the methods of chemical analysis were the same throughout the study, while for others, the methods changed as analytical technology improved. However, all the methods used were specifically designed to give the total contents of the element analyzed. Therefore, the results of earlier analysis should be comparable with results of more recent analyses.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints: None
303-236-1849 (voice)
303-236-3200 (FAX)
dsmith@usgs.gov
The U.S. Geological Survey (USGS) provides these data "as is". The USGS makes no guarantee or warranty concerning the accuracy of information contained in the geographic data. The USGS further makes no warranties, either expressed or implied as to any other matter, whatsoever, including, without limitation, the condition of the product, or its fitness for any particular purpose. The burden for determining fitness for use lies entirely with the user.
Data format: | Geochemical sample locations and analytic results in format ESRI shapefile (version 1.0) Size: 0.125 megabytes |
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Network links: |
<http://tin.er.usgs.gov/ussoils/ussoils.zip> |
303-236-1849 (voice)
303-236-3200 (FAX)
dsmith@usgs.gov