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The geochemical landscape of northwestern Wisconsin and adjacent parts of northern Michigan and Minnesota (geochemical data files)

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
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• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
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• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
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  3. How accurate are the heights or depths?
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• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?

   Cannon, William F. , and Woodruff, Laurel G. , 2003, The geochemical landscape of northwestern Wisconsin and adjacent parts of northern Michigan and Minnesota (geochemical data files): U.S. Geological Survey Open-File Report 03-259, U.S. Geological Survey, Reston VA.

   Online Links:

   • <http://pubs.usgs.gov/of/2003/of03-259/>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -92.0000

   East_Bounding_Coordinate: -90.0000

   North_Bounding_Coordinate: 47.0000

   South_Bounding_Coordinate: 45.0000

3. What does it look like?

   Sample location map (jpeg)

   Map showing the location of study area and distribution of soil, stream sediment and lake sediment samples for which analyses are reported.

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 1978

   Ending_Date: 2000

   Currentness_Reference:

   Data were acquired over a span of more than 20 years. Data in NURE_original and NURE_ls are analyses done in 1978-79 on samples collected those same years. Data in A_soil, B_soil, C_soil, an E_soil are analyses done from 1997-2000 on samples collected from about 1985-1990 for Forest Service samples and from 1996-2000 for USGS samples. Data in NURE_rean are analyses conducted in 1997. Data in USGS_lsed are analyses conducted in 2000 on samples collected that same year.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: data tables

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Point data set. It contains the following vector data types (SDTS terminology):

      • Entity point

   2. What coordinate system is used to represent geographic features?

      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0001. Longitudes are given to the nearest 0.0001. Latitude and longitude values are specified in decimal degrees.

7. How does the data set describe geographic features?

   A_soil.dbf

   Multi-element chemical analyses for A-horizon soil samples. Includes site ID and lat/long. Quantitative results for 31 elements. 11 additional elements were analyzed but reported below detection limit for 90% to 100% of samples tested. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Mo(2), Sn(50), Ta(40), U(100).

   Sample_no

   Unique identification number for sample

   text identifier without scientific significance

   SAMP_SOURC

   Agency responsible for sample collection

   Value	Definition
   FS	USDA Forest Service
   USGS	U.S. Geological Survey

   X_COORD

   Longitude of sample site

   Range of values
   Minimum:	-90
   Maximum:	-92
   Units:	decimal degrees
   Resolution:	0.0001

   Y_COORD

   Attribute_Domain_Values

   Range of values
   Minimum:	45
   Maximum:	47
   Units:	decimal degrees
   Resolution:	0.0001

   DEPTH_AVE

   Average depth of interval sampled

   Range of values
   Minimum:	0.50
   Maximum:	36.50
   Units:	inches
   Resolution:	1

   Depth_rng

   depth of top and bottom of sampled interval in inches

   typically a top and bottom in inches, sometimes followed by a word descriptive of the material

   HORIZON

   designation of soil horizon

   Value	Definition
   A	code from standard soil nomenclature

   AL

   concentration of aluminum in percent determined by inductively couple plasma atomic emission spectroscopy

   Range of values
   Minimum:	1.105
   Maximum:	8.385
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	1.20
   Maximum:	13.40
   Units:	parts per million
   Resolution:	0.01

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	212
   Maximum:	1250
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.075
   Maximum:	3.084
   Units:	weight percent
   Resolution:	0.001

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	19
   Maximum:	97
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	38
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	1
   Maximum:	876
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	155
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.42
   Maximum:	7.24
   Units:	weight percent
   Resolution:	0.01

   Ga

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	Proxy value for samples reporting less than the detection limit of 4 ppm

   Range of values
   Minimum:	3
   Maximum:	26
   Units:	parts per million
   Resolution:	1

   Hg

   concentration of total mercury in parts per million determined by cold vapor atomic absorption spectroscopy. Values of 0.01 indicate below detection limit of 0.02 ppm.

   Value	Definition
   0.01	Proxy value for samples reporting less than the detection limit of 0.02 ppm

   Range of values
   Minimum:	0.01
   Maximum:	0.30
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.72
   Maximum:	2.23
   Units:	weight percent
   Resolution:	0.01

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	44
   Units:	parts per million
   Resolution:	1

   LI

   concentration of lithium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	35
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.039
   Maximum:	1.520
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	56
   Maximum:	6610
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.135
   Maximum:	1.174
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	proxy value assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	6
   Maximum:	16
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 5 indicate below detection limit.

   Value	Definition
   5	proxy values assigned to samples reporting less than 9 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	41
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate below detection limit.

   Value	Definition
   2	proxy value assigned samples reporting less than 3 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	82
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.005
   Maximum:	0.514
   Units:	weight percent
   Resolution:	1

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	64
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	proxy value assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	22
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	0.10
   Maximum:	2.00
   Units:	parts per million
   Resolution:	0.01

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	30
   Maximum:	141
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 4 indicate below detection limit.

   Value	Definition
   4	proxy value assigned to samples reporting less than 6 ppm detection limit

   Range of values
   Minimum:	4
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.085
   Maximum:	1.393
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	16
   Maximum:	162
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	6
   Maximum:	39
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	proxy value assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	3
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	7
   Maximum:	844
   Units:	parts per million
   Resolution:	1

   B_soil.dbf

   Multi-element chemical analyses for B-horizon soil samples. Includes site ID and lat/long. Quantitative results for 31 elements. 11 additional elements were analyzed but reported below detection limit for 90% to 100% of samples tested. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Mo(2), Sn(50), Ta(40), U(100).

   Sample_no

   Unique identification number for sample

   text identifier without scientific significance

   SAMP_SOURC

   Agency responsible for sample collecting

   Value	Definition
   FS	USDA Forest Service

   X_COORD

   Longitude of sample site

   Range of values
   Minimum:	-90
   Maximum:	-92
   Units:	decimal degrees
   Resolution:	0.0001

   Y_COORD

   Latitude of sample site

   Range of values
   Minimum:	45
   Maximum:	47
   Units:	decimal degrees
   Resolution:	0.001

   DEPTH_AVE

   Average depth of interval sampled

   Range of values
   Minimum:	0.50
   Maximum:	36.50
   Units:	inches
   Resolution:	1

   Depth_rng

   depth of top and bottom of sampled interval in inches

   typically a top and bottom in inches, sometimes followed by a word descriptive of the material

   HORIZON

   designation of soil horizon

   Value	Definition
   A	code from standard soil nomenclature

   AL

   concentration of aluminum in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	1.283
   Maximum:	6.677
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	2.00
   Maximum:	29.2
   Units:	parts per million
   Resolution:	0.01

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	165
   Maximum:	738
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.213
   Maximum:	5.715
   Units:	percent
   Resolution:	0.001

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	20
   Maximum:	107
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	3
   Maximum:	49
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	proxy values assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	37
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	4
   Maximum:	82
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in weight percent determined by inductively coupled plasma atomic emission spectroscopy:

   Range of values
   Minimum:	0.73
   Maximum:	11.8
   Units:	weight percent
   Resolution:	0.01

   Ga

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	13
   Units:	parts per million
   Resolution:	1

   Hg

   concentration of total mercury in parts per million determined by cold vapor atomic absorption spectroscopy. Values of 0.01 indicate below detection limit of 0.02 ppm.

   Value	Definition
   0.01	Proxy value for samples reporting less than the detection limit of 0.02 ppm

   Range of values
   Minimum:	0.01
   Maximum:	0.17
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.380
   Maximum:	2.870
   Units:	weight percent
   Resolution:	0.001

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	48
   Units:	parts per million
   Resolution:	1

   LI

   concentration of lithium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	4
   Maximum:	18
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic absorption spectroscopy

   Range of values
   Minimum:	0.081
   Maximum:	2.894
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	56
   Maximum:	6610
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.135
   Maximum:	1.174
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	Proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	16
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 5 indicate below detection limit.

   Value	Definition
   5	Proxy values assigned to samples reporting less than 9 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	72
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate below detection limit.

   Value	Definition
   2	Proxy value assigned to samples reporting less than the 3 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	82
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.005
   Maximum:	0.514
   Units:	weight percent
   Resolution:	1

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	64
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	3
   Maximum:	32
   Units:	parts per million
   Resolution:	1

   SE

   concentration of scandium in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	0.10
   Maximum:	0.7
   Units:	parts per million
   Resolution:	0.01

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	35
   Maximum:	220
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 4 indicate below detection limit.

   Value	Definition
   4	Proxy value assigned to samples reporting less than 6 ppm detection limit

   Range of values
   Minimum:	4
   Maximum:	8
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.088
   Maximum:	1.679
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	22
   Maximum:	249
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	8
   Maximum:	80
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Proxy values assigned samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	6
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	624
   Units:	parts per million
   Resolution:	1

   C_soil.dbf

   Multi-element chemical analyses for C-horizon soil samples. Includes site ID and lat/long. Quantitative results for 31 elements. 11 additional elements were analyzed but reported below detection limit for 90% to 100% of samples tested. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Mo(2), Sn(50), Ta(40), U(100).

   Sample_no

   Unique identification number for sample

   text identifier without scientific significance

   SAMP_SOURC

   agency responsible for collecting sample

   Value	Definition
   FS	USDA Forest Service

   X_COORD

   Longitude of sample site

   Range of values
   Minimum:	-90
   Maximum:	-92
   Units:	decimal degrees
   Resolution:	0.0001

   Y_COORD

   latitude of sample site

   Range of values
   Minimum:	45
   Maximum:	47
   Units:	decimal degrees
   Resolution:	0.001

   DEPTH_AVE

   Average depth of interval sampled

   Range of values
   Minimum:	0.50
   Maximum:	36.50
   Units:	inches
   Resolution:	1

   Depth_rng

   depth of top and bottom of sampled interval in inches

   typically a top and bottom in inches, sometimes followed by a word descriptive of the material

   HORIZON

   designation of soil horizon

   Value	Definition
   A	code from standard soil nomenclature

   AL

   concentration of aluminum in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.800
   Maximum:	8.400
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	1.10
   Maximum:	18.90
   Units:	parts per million
   Resolution:	0.01

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	157
   Maximum:	783
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.095
   Maximum:	2.585
   Units:	weight percent
   Resolution:	0.001

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	17
   Maximum:	167
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	proxy values assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	27
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	proxy values assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	118
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	100
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in percent determined by inductively coupled plasma atomic emission spectroscopy:

   Range of values
   Minimum:	0.300
   Maximum:	6.720
   Units:	weight percent
   Resolution:	0.001

   Ga

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	24
   Units:	parts per million
   Resolution:	1

   Hg

   concentration of total mercury in parts per million determined by cold vapor atomic absorption spectroscopy. Values of 0.01 indicate below detection limit of 0.02 ppm.

   Value	Definition
   0.01	Proxy value for samples reporting less than the detection limit of 0.02 ppm

   Range of values
   Minimum:	0.01
   Maximum:	0.12
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.78
   Maximum:	2.96
   Units:	weight percent
   Resolution:	0.01

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	55
   Units:	parts per million
   Resolution:	1

   LI

   concentration of lithium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	2
   Maximum:	40
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.075
   Maximum:	1.760
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	57
   Maximum:	4120
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.090
   Maximum:	1.742
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	Proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	15
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 5 indicate below detection limit.

   Value	Definition
   5	Proxy values assigned to samples reporting less than 9 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	49
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate below detection limit.

   Value	Definition
   2	Proxy value assigned to samples reporting less than the 3 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	84
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.005
   Maximum:	0.221
   Units:	weight percent
   Resolution:	0.001

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	48
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	3
   Maximum:	22
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	0.10
   Maximum:	1.8
   Units:	parts per million
   Resolution:	0.01

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	25
   Maximum:	212
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 4 indicate below detection limit.

   Value	Definition
   4	Proxy value assigned to samples reporting less than 6 ppm detection limit

   Range of values
   Minimum:	4
   Maximum:	20
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.054
   Maximum:	1.187
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	11
   Maximum:	236
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	7
   Maximum:	38
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Proxy values assigned samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	5
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	6
   Maximum:	207
   Units:	parts per million
   Resolution:	1

   E_soil.dbf

   Multi-element chemical analyses for E-horizon soil samples. Includes site ID and lat/long. Quantitative results for 31 elements. 11 additional elements were analyzed but reported below detection limit for 90% to 100% of samples tested. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Mo(2), Sn(50), Ta(40), U(100).

   Sample_no

   Unique identification number for sample

   text identifier without scientific significance

   SAMP_SOURC

   Agency responsible for collecting sample

   Value	Definition
   FS	USDA Forest Service

   X_COORD

   Longitude of sample site

   Range of values
   Minimum:	-90
   Maximum:	-92
   Units:	decimal degrees
   Resolution:	0.0001

   Y_COORD

   latitude of sample site

   Range of values
   Minimum:	45
   Maximum:	47
   Units:	decimal degrees
   Resolution:	0.001

   DEPTH_AVE

   Average depth of interval sampled

   Range of values
   Minimum:	0.50
   Maximum:	22.0
   Units:	inches
   Resolution:	1

   Depth_rng

   depth of top and bottom of sampled interval in inches

   typically a top and bottom in inches, sometimes followed by a word descriptive of the material

   HORIZON

   designation of soil horizon

   Value	Definition
   A	code from standard soil nomenclature

   AL

   concentration of aluminum in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	1.443
   Maximum:	5.499
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	2.0
   Maximum:	8.5
   Units:	parts per million
   Resolution:	0.01

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	274
   Maximum:	815
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.129
   Maximum:	1.012
   Units:	percent
   Resolution:	0.001

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	19
   Maximum:	73
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	proxy values assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	2
   Maximum:	39
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy Values of 1 indicate less than detection limit.

   Range of values
   Minimum:	4
   Maximum:	22
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in weight percent determined by inductively coupled plasma atomic emission spectroscopy:

   Range of values
   Minimum:	0.30
   Maximum:	6.72
   Units:	weight percent
   Resolution:	0.01

   Ga

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	12
   Units:	parts per million
   Resolution:	1

   Hg

   concentration of total mercury in parts per million determined by cold vapor atomic absorption spectroscopy. Values of 0.01 indicate below detection limit of 0.02 ppm.

   Value	Definition
   0.01	Proxy value for samples reporting less than the detection limit of 0.02 ppm

   Range of values
   Minimum:	0.01
   Maximum:	0.14
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	1.09
   Maximum:	2.07
   Units:	weight percent
   Resolution:	0.01

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	10
   Maximum:	39
   Units:	parts per million
   Resolution:	1

   LI

   concentration of lithium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	21
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.073
   Maximum:	0.727
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	126
   Maximum:	3450
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.199
   Maximum:	1.294
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate below detection limit.

   Value	Definition
   3	Proxy values assigned to samples reporting less than 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	14
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 5 indicate below detection limit.

   Value	Definition
   5	Proxy values assigned to samples reporting less than 9 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	32
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate below detection limit.

   Range of values
   Minimum:	2
   Maximum:	23
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.009
   Maximum:	0.070
   Units:	weight percent
   Resolution:	0.001

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	8
   Maximum:	26
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	9
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	0.14
   Maximum:	1.00
   Units:	parts per million
   Resolution:	0.01

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	36
   Maximum:	145
   Units:	parts per million

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 4 indicate below detection limit.

   Value	Definition
   4	Proxy value assigned to samples reporting less than 6 ppm detection limit

   Range of values
   Minimum:	4
   Maximum:	10
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.172
   Maximum:	0.510
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	29
   Maximum:	107
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	7
   Maximum:	21
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	7
   Maximum:	21
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	6
   Maximum:	207
   Units:	parts per million
   Resolution:	1

   usgs_ls.dbf

   Multi-element chemical analyses for lake-bottom sediment samples. Includes site ID, lake name, water depth at sample site, and lat/long. Quantitative results for 36 elements. 10 additional elements were analyzed but reported below detection limit for 90% to 100% of samples tested. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Sn(50), Ta(40), U(100).

   SAMPLE

   unique identifying number for sample

   identifier without scientific significance

   LAKE_NAME

   name of lake from which sample was collected

   geographic name

   DEPTH

   depth of water at sample site in feet

   Range of values
   Minimum:	0.0
   Maximum:	40.0
   Units:	feet
   Resolution:	1

   X_COORD

   longitude of sample site

   Range of values
   Minimum:	-91.92237
   Maximum:	-90.06391
   Units:	decimal degrees
   Resolution:	0.0001

   Y_COORD

   latitude of sample site

   Range of values
   Minimum:	45.10781
   Maximum:	46.79576
   Units:	decimal degrees
   Resolution:	0.0001

   AL

   concentration of aluminum in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.955
   Maximum:	5.385
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy.

   Range of values
   Minimum:	1.75
   Maximum:	66.70
   Units:	ppm
   Resolution:	0.01

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	109
   Maximum:	508
   Units:	ppm
   Resolution:	1

   CA

   concentration of calcium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.247
   Maximum:	1.748
   Units:	weight percent
   Resolution:	0.001

   C_ORG

   concentration of organic carbon in weight percent

   Range of values
   Minimum:	0.29
   Maximum:	36.28
   Units:	weight percent
   Resolution:	0.01

   C_CRBNT

   concentration of carbonate carbon in weight percent determined by coulometric titration

   Range of values
   Minimum:	0.00
   Maximum:	0.26
   Units:	weight percent
   Resolution:	0.01

   C_TOT

   concentration of total carbon in weight percent determined by automated carbon analyzer

   Range of values
   Minimum:	0.29
   Maximum:	36.30
   Units:	weight percent
   Resolution:	0.01

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	82
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	2
   Maximum:	18
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	13
   Maximum:	101
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	2
   Maximum:	71
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.43
   Maximum:	17.20
   Units:	weight percent
   Resolution:	0.01

   GA

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate less than detection limit.

   Value	Definition
   3	Proxy value assigned to samples reporting less than the 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	21
   Units:	parts per million
   Resolution:	1

   HG

   concentration of total mercury determined by cold vapor atomic absorption spectroscopy. Values of 0.014 indicate les than detection limit.

   Value	Definition
   0.014	Proxy value assigned to samples reporting less than the 0.02 ppm detection limit

   Range of values
   Minimum:	0.014
   Maximum:	0.360
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.14
   Maximum:	2.11
   Units:	weight percent
   Resolution:	0.01

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	4
   Maximum:	44
   Units:	parts per million
   Resolution:	1

   LI

   concentration of lithium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	3
   Maximum:	26
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.114
   Maximum:	1.155
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	85
   Maximum:	4450
   Units:	parts per million
   Resolution:	1

   MO

   concentration of molybdenum in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	7
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.060
   Maximum:	1.043
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate less than detection limit.

   Value	Definition
   3	Proxy value assigned to samples reporting less than the 4 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	22
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 6 indicate less than detection limit.

   Value	Definition
   6	Proxy values assigned to samples reporting less than the 9 ppm detection limit

   Range of values
   Minimum:	6
   Maximum:	60
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate less than detection limit.

   Value	Definition
   2	Proxy value assigned to samples reporting less than the 3 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	35
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.010
   Maximum:	0.380
   Units:	weight percent
   Resolution:	0.001

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	69
   Units:	parts per million
   Resolution:	1

   S

   concentration of sulfur in weight percent determined by automated sulfur analyzer

   Range of values
   Minimum:	0.04
   Maximum:	1.46
   Units:	weight percent
   Resolution:	0.04

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy values assigned samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	12
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts pr million determined by hydride generation atomic absorption spectroscopy. Values of 0.14 indicate less than detection limit.

   Value	Definition
   0.14	Proxy value assigned to samples reporting les than the 0.2 ppm detection limit

   Range of values
   Minimum:	0.14
   Maximum:	5.00
   Units:	parts per million
   Resolution:	0.1

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	22
   Maximum:	133
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 4 indicate less than detection limit.

   Value	Definition
   4	Proxy values assigned to samples reporting less than the 6 ppm detection limit

   Range of values
   Minimum:	4
   Maximum:	9
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.054
   Maximum:	0.449
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	17
   Maximum:	290
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy.

   Range of values
   Minimum:	5
   Maximum:	34
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	3
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	10
   Maximum:	445
   Units:	parts per million
   Resolution:	1

   nure_ls.dbf

   Multi-element chemical analyses for lake-bottom sediment samples collect during the NURE program. Includes site ID, lake name, and lat/long. Quantitative results for 10 elements.

   ID

   unique sample identification number

   identifier without scientific significance

   LAKENAME

   name of lake from which sample was collected

   geographic name

   X_COORD

   longitude of sample site

   Range of values
   Minimum:	-91.995
   Maximum:	-90.012
   Units:	decimal degrees
   Resolution:	0.001

   Y_COORD

   latitude of sample site

   Range of values
   Minimum:	45.005
   Maximum:	46.796
   Units:	decimal degrees
   Resolution:	0.001

   QUAD

   name of NTMS quadrangle containing sample site

   Value	Definition
   Ashland
   Ricelake

   U3O8

   concentration of uranium oxide (U3O8) in parts per million

   Value	Definition
   -9999.9	value assigned to samples for which analysis was not performed

   Range of values
   Minimum:	0.4
   Maximum:	28.0
   Units:	parts per million
   Resolution:	0.1

   LOI__

   loss on ignition in weight percent

   Value	Definition
   -999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	1
   Maximum:	86
   Units:	weight percent
   Resolution:	1

   AS

   concentration of arsenic in parts per million

   Value	Definition
   -9999.9	value assigned to samples for which analysis was not performed
   3	Proxy value assigned to samples reporting less than the 5 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	45.0
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million

   Value	Definition
   -9999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	5
   Maximum:	495
   Units:	parts per million
   Resolution:	1

   MO

   concentration of molybdenum in parts per million. Values of 0.5 indicate less than detection limit.

   Value	Definition
   0.5	Proxy values assigned to samples reporting less than the 1 ppm detection limit
   -9999	value assigned to samples for which analyses was not performed

   Range of values
   Minimum:	0.5
   Maximum:	54.0
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million

   Value	Definition
   -9999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	5
   Maximum:	1000
   Units:	parts per million
   Resolution:	1

   PB

   concentration of lead in parts per million

   Value	Definition
   -9999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	5
   Maximum:	430
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts per million. Values of 0.5 indicate less than detection limit.

   Value	Definition
   0.5	Proxy value assigned to samples reporting less than the 1 ppm detection limit
   -9999.9	value assigned to samples for which analysis was not performed

   Range of values
   Minimum:	0.5
   Maximum:	51.0
   Units:	parts per million
   Resolution:	1

   V

   concentration of vanadium oxide (V2O5) in parts per million

   Value	Definition
   -9999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	30
   Maximum:	860
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million

   Value	Definition
   -9999	value assigned to samples for which analyses were not performed

   Range of values
   Minimum:	5
   Maximum:	540
   Units:	parts per million
   Resolution:	1

   nure_original.dbf

   Multi-element analyses of stream sediments collected and analyzed during the NURE program. Includes ID, lat/long, quadrangle name. Quantitative results for 28 elements.

   UNIQID

   unique identification number for sample

   Range of values
   Minimum:	6002912
   Maximum:	6017773

   QUAD_NAME

   name of NTMS quadrangle containing sample site

   Value	Definition
   Ashland
   Rice Lake

   LAT

   latitude of sample site

   Range of values
   Minimum:	45.002
   Maximum:	46.984
   Units:	decimal degrees
   Resolution:	0.001

   LONG

   longitude of sample site

   Range of values
   Minimum:	-91.995
   Maximum:	-90.002
   Units:	decimal degrees
   Resolution:	0.001

   AL

   concentration of aluminum in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.74
   Maximum:	7.96
   Units:	weight percent
   Resolution:	0.01

   AS

   concentration of arsenic in parts per million determined by atomic absorption spectroscopy

   Range of values
   Minimum:	0.2
   Maximum:	29.4
   Units:	parts per million
   Resolution:	0.1

   B

   concentration of boron in parts per million determined by plasma source emission spectroscopy. Values of 5 indicate below detection limit.

   Value	Definition
   -999	value assigned to samples for which analysis was not performed
   5	Value assigned to samples reporting less than the 10 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	62
   Units:	parts per million
   Resolution:	1

   BA

   concentration of barium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	95
   Maximum:	1237
   Units:	parts per million
   Resolution:	1

   BE

   concentration of beryllium in parts per million determined by plasma source emission spectroscopy. Values of 0.5 indicate below detection limit.

   Value	Definition
   0.5	Value assigned to samples reporting less than the 1 ppm detection limit

   Range of values
   Minimum:	0.5
   Maximum:	9.0
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.11
   Maximum:	3.36
   Units:	weight percent
   Resolution:	0.01

   CO

   concentration of cobalt in parts per million determined by plasma source emission spectroscopy. Values of 2 indicate below detection limit.

   Value	Definition
   2	Value assigned to samples reporting less than the 4 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	53
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	9
   Maximum:	167
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by plasma source emission spectroscopy. Value of 1 indicates below detection limit.

   Value	Definition
   1	Value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	398
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.37
   Maximum:	7.95
   Units:	weight percent
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.22
   Maximum:	2.63
   Units:	weight percent
   Resolution:	0.01

   LI

   concentration of lithium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	1
   Maximum:	33
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.069
   Maximum:	2.479
   Units:	weight percent
   Resolution:	0.01

   MN

   concentration of manganese in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	95
   Maximum:	9600
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by plasma source emission spectroscopy

   Range of values
   Minimum:	0.159
   Maximum:	1.669
   Units:	weight percent
   Resolution:	0.01

   NB

   concentration of lithium in parts per million determined by plasma source emission spectroscopy. Values of 2 indicate below detection limit.

   Value	Definition
   2	Value assigned to samples reporting less the 4 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	36
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by plasma source emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Value assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	46
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	58
   Maximum:	2376
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	1
   Maximum:	27
   Units:	parts per million
   Resolution:	1

   SE

   concentration of selenium in parts per million determined by atomic absorption spectroscopy

   Range of values
   Minimum:	0.2
   Maximum:	10.1
   Units:	parts per million
   Resolution:	0.1

   SR

   concentration of strontium in parts per million determined by plasma source emission spectroscopy

   Value	Definition
   -999	value assigned to samples for which analysis was not performed

   Range of values
   Minimum:	32
   Maximum:	319
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by plasma source emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Value assigned to samples reporting less than 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	108
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	825
   Maximum:	20456
   Units:	parts per million
   Resolution:	1

   U

   concentration of uranium in parts per million determined by flourometry

   Range of values
   Minimum:	0.43
   Maximum:	119.60
   Units:	parts per million
   Resolution:	0.01

   V

   concentration of vanadium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	14
   Maximum:	222
   Units:	parts per million
   Resolution:	1

   Y

   concentration of vanadium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	39
   Units:	parts per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million determined by plasma source emission spectroscopy. Values of 1 indicate below detection limit.

   Value	Definition
   1	Proxy values assigned to samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	172
   Units:	parts per million
   Resolution:	1

   Zr

   concentration of zirconium in parts per million determined by plasma source emission spectroscopy

   Range of values
   Minimum:	19
   Maximum:	361
   Units:	parts per million
   Resolution:	1

   nure_rean.dbf

   Multi-element chemical analyses of stream sediments. Samples are a subset of the original NURE stream sediment samples reported in file NURE_original of this report, which were reanalyzed using USGS methods. Quantitative data for 30 elements. Analyses were also done for 10 additional elements which contained less than detection limits for 90-100% of samples. Those elements and their detection limits in parts per million are: Ag(2), Au(8), Be(1), Bi(50), Cd(2), Eu(2), Ho(4), Sn(50), Ta(40), U(100).

   LAB_NO

   unique identification numbers assigned by USGS to reanalyzed samples

   identifier without further scientific significance

   FIELD_NO_

   unique identification numbers assigned to samples by the original NURE program

   Value	Definition
   -9999	proxy value assigned where value is missing

   Range of values
   Minimum:	600566
   Maximum:	751056

   LONG

   longitude of sample site

   Range of values
   Minimum:	-91.998
   Maximum:	-90.013
   Units:	decimal degrees
   Resolution:	0.001

   LAT

   latitude of sample site

   Range of values
   Minimum:	45.003
   Maximum:	46.985
   Units:	decimal degrees
   Resolution:	0.001

   AL

   concentration of aluminum in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	1.250
   Maximum:	8.795
   Units:	weight percent
   Resolution:	0.001

   AS

   concentration of arsenic in parts per million determined by hydride generation atomic absorption spectroscopy

   Range of values
   Minimum:	0.3
   Maximum:	23.0
   Units:	parts per million
   Resolution:	0.1

   BA

   concentration of barium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	306
   Maximum:	778
   Units:	parts per million
   Resolution:	1

   CA

   concentration of calcium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.460
   Maximum:	3.355
   Units:	weight percent
   Resolution:	0.001

   CE

   concentration of cerium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	23
   Maximum:	104
   Units:	parts per million
   Resolution:	1

   CO

   concentration of cobalt in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	3
   Maximum:	49
   Units:	parts per million
   Resolution:	1

   CR

   concentration of chromium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy values assigned samples reporting less than the 2 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	138
   Units:	parts per million
   Resolution:	1

   CU

   concentration of copper in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	4
   Maximum:	65
   Units:	parts per million
   Resolution:	1

   FE

   concentration of iron in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.87
   Maximum:	6.35
   Units:	weight percent
   Resolution:	0.01

   GA

   concentration of gallium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate less than detection limit.

   Value	Definition
   2	Proxy values assigned to samples reporting less than the 4 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	25
   Units:	parts per million
   Resolution:	1

   HG

   concentration of total mercury in parts per million determined by cold vapor atomic absorption spectroscopy. Values of 0.01 indicate less than detection limit.

   Value	Definition
   0.01	Proxy values assigned to samples reporting less than the 0.02 detection limit

   Range of values
   Minimum:	0.01
   Maximum:	0.28
   Units:	parts per million
   Resolution:	0.01

   K

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.77
   Maximum:	3.02
   Units:	weight percent
   Resolution:	0.01

   LA

   concentration of lanthanum in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	10
   Maximum:	46
   Units:	parts per million
   Resolution:	1

   LI

   concentration of potassium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	4
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   MG

   concentration of magnesium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.221
   Maximum:	2.065
   Units:	weight percent
   Resolution:	0.001

   MN

   concentration of manganese in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	199
   Maximum:	9210
   Units:	parts per million
   Resolution:	1

   NA

   concentration of sodium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.395
   Maximum:	2.043
   Units:	weight percent
   Resolution:	0.001

   NB

   concentration of niobium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate less than detection limit.

   Value	Definition
   2	Proxy value assigned to samples reporting les than the 4 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	32
   Units:	parts per million
   Resolution:	1

   ND

   concentration of neodymium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 5 indicate less than detection limit.

   Value	Definition
   5	Proxy value assigned to samples reporting less than the 9 ppm detection limit

   Range of values
   Minimum:	5
   Maximum:	45
   Units:	parts per million
   Resolution:	1

   NI

   concentration of nickel in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	8
   Maximum:	63
   Units:	parts per million
   Resolution:	1

   P

   concentration of phosphorous in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.005
   Maximum:	9.000
   Units:	weight percent
   Resolution:	0.001

   PB

   concentration of lead in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 2 indicate less than detection limit.

   Value	Definition
   2	Proxy value assigned to samples reporting less than the 4 ppm detection limit

   Range of values
   Minimum:	2
   Maximum:	336
   Units:	parts per million
   Resolution:	1

   SC

   concentration of scandium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	2
   Maximum:	19
   Units:	parts per million
   Resolution:	1

   SR

   concentration of strontium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	67
   Maximum:	260
   Units:	parts per million
   Resolution:	1

   TH

   concentration of thorium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 3 indicate less than detection limit.

   Value	Definition
   3	Proxy values assigned to samples reporting less than the 6 ppm detection limit

   Range of values
   Minimum:	3
   Maximum:	22
   Units:	parts per million
   Resolution:	1

   TI

   concentration of titanium in weight percent determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	0.192
   Maximum:	1.446
   Units:	weight percent
   Resolution:	0.001

   V

   concentration of vanadium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	29
   Maximum:	216
   Units:	parts per million
   Resolution:	1

   Y

   concentration of yttrium in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	8
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   YB

   concentration of ytterbium in parts per million determined by inductively coupled plasma atomic emission spectroscopy. Values of 1 indicate less than detection limit.

   Value	Definition
   1	Proxy value assigned to samples reporting less than the 1 ppm detection limit

   Range of values
   Minimum:	1
   Maximum:	4
   Units:	part per million
   Resolution:	1

   ZN

   concentration of zinc in parts per million determined by inductively coupled plasma atomic emission spectroscopy

   Range of values
   Minimum:	17
   Maximum:	228
   Units:	parts per million
   Resolution:	1

   nuress_adj.dbf

   Multi-element chemical composition for stream sediment samples. Data consists of original NURE values for some elements, and, where appropriate, of recalculated values based on consistent variations between original NURE data and data derived from USGS reanalysis of NURE samples.

   UNIQID

   unique sample identification number from original NURE program

   Range of values
   Minimum:	6002912
   Maximum:	6017773

   QUAD_NAME

   name of NTMS quadrangle containing sample site

   Value	Definition
   Ashland
   Rice Lake

   LAT

   latitude of sample site

   Range of values
   Minimum:	45.002
   Maximum:	46.984
   Units:	decimal degrees
   Resolution:	0.001

   LONG

   longitude of sample site

   Range of values
   Minimum:	-91.995
   Maximum:	-90.002
   Units:	decimal degrees
   Resolution:	0.001

   AL_ADJ

   recalculated concentration of aluminum in weight percent

   Range of values
   Minimum:	0.207
   Maximum:	8.481
   Units:	weight percent
   Resolution:	0.001

   AS_ADJ

   recalculated concentration of arsenic in parts per million

   Range of values
   Minimum:	1.8
   Maximum:	32.0
   Units:	parts per million
   Resolution:	0.1

   B_OR

   original NURE values for boron concentration in parts per million

   Value	Definition
   -999	missing values

   Range of values
   Minimum:	5
   Maximum:	62
   Units:	parts per million
   Resolution:	1

   BA_ADJ

   recalculated concentration of barium in parts per million

   Range of values
   Minimum:	207
   Maximum:	749
   Units:	parts per million
   Resolution:	1

   CA_ADJ

   recalculated concentration of calcium in weight percent

   Range of values
   Minimum:	0.448
   Maximum:	3.476
   Units:	weight percent
   Resolution:	0.001

   CO_ADJ

   recalculated concentration of cobalt in parts per million

   Range of values
   Minimum:	1
   Maximum:	24
   Units:	parts per million
   Resolution:	1

   CR_ADJ

   recalculated concentration of chromium in parts per million

   Range of values
   Minimum:	5
   Maximum:	151
   Units:	parts per million
   Resolution:	1

   CU_ADJ

   recalculated concentration of copper in parts per million

   Value	Definition
   -999	missing value

   Range of values
   Minimum:	2
   Maximum:	347
   Units:	parts per million
   Resolution:	1

   FE_ADJ

   recalculated concentration of iron in weight percent

   Range of values
   Minimum:	0.42
   Maximum:	9.18
   Units:	weight percent
   Resolution:	0.01

   K_ADJ

   recalculated concentration of potassium in weight percent

   Range of values
   Minimum:	0.41
   Maximum:	2.97
   Units:	weight percent
   Resolution:	0.01

   LI_ADJ

   recalculated concentration of lithium in parts per million

   Value	Definition
   -999	missing values

   Range of values
   Minimum:	3
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   MG_ADJ

   recalculated concentration of magnesium in weight percent

   Range of values
   Minimum:	0.211
   Maximum:	1.955
   Units:	weight percent
   Resolution:	0.001

   MN_ADJ

   recalculated concentration of manganese in parts per million

   Range of values
   Minimum:	84
   Maximum:	8811
   Units:	parts per million
   Resolution:	1

   NA_ADJ

   recalculated concentration of sodium in weight percent

   Range of values
   Minimum:	0.335
   Maximum:	1.610
   Units:	weight percent
   Resolution:	0.001

   NB_OR

   original NURE values for concentration of niobium in parts per million

   Range of values
   Minimum:	2
   Maximum:	36
   Units:	parts per million
   Resolution:	1

   NI_OR

   original NURE values for concentration of nickel in parts per million

   Range of values
   Minimum:	1
   Maximum:	46
   Units:	parts per million
   Resolution:	1

   P_ADJ

   recalculated concentration of phosphorous in parts per million

   Range of values
   Minimum:	80
   Maximum:	2756
   Units:	parts per million
   Resolution:	1

   SC_ADJ

   recalculated concentration of scandium in parts per million

   Range of values
   Minimum:	1
   Maximum:	21
   Units:	parts per million
   Resolution:	1

   SE_OR

   original NURE value for concentration of selenium in parts per million

   Value	Definition
   -999	missing values

   Range of values
   Minimum:	0.2
   Maximum:	10.1
   Units:	parts per million
   Resolution:	0.1

   SR_ADJ

   recalculated concentration of strontium in parts per million

   Value	Definition
   -999	missing values

   Range of values
   Minimum:	49
   Maximum:	177
   Units:	parts pre million
   Resolution:	1

   TH_ADJ

   recalculated concentration of thorium in parts per million

   Range of values
   Minimum:	1
   Maximum:	28
   Units:	parts per million
   Resolution:	1

   TI_ADJ

   recalculated concentration of titanium in parts per million

   Range of values
   Minimum:	1234
   Maximum:	26305
   Units:	parts per million
   Resolution:	1

   U_OR

   original NURE value reported for concentration of uranium in parts per million

   Range of values
   Minimum:	0.429
   Maximum:	119.599
   Units:	pars per million
   Resolution:	0.01

   V_ADJ

   recalculated concentration of vanadium in parts per million

   Range of values
   Minimum:	15
   Maximum:	233
   Units:	parts per million
   Resolution:	1

   Y_ADJ

   recalculated concentration of yttrium in parts per million

   Range of values
   Minimum:	6
   Maximum:	34
   Units:	parts per million
   Resolution:	1

   ZR_OR

   original NURE value reported for concentration of zirconium in parts per million

   Range of values
   Minimum:	19
   Maximum:	380
   Units:	parts per million
   Resolution:	1

   ZN_ADJ

   recalculated concentration of zinc in parts per million

   Value	Definition
   -999	missing values

   Range of values
   Minimum:	6
   Maximum:	203
   Units:	parts per million
   Resolution:	1

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • William F. Cannon
   • Laurel G. Woodruff

2. Who also contributed to the data set?

   U.S. Geological Survey

3. To whom should users address questions about the data?
   William Cannon
   Geologist
   U.S. Geological Survey, Mail Stop 954
   Reston, Virginia 20192
   USA
   

   703-648-6345 (voice)
   wcannon@usgs.gov
   

Why was the data set created?

This study was conducted to provide information on the geochemical background and baseline values of a suite of elements in a part of northern Wisconsin including the Chequamegon National Forest. The resulting chemical analyses are useful both for documenting the natural variability of elements, but also provide a base of data to conduct research on geochemical and physical processes that control and modify the chemical composition of surficial geologic materials and to develop optimal sampling and analytical strategies for other studies in similar terranes.

How was the data set created?

1. From what previous works were the data drawn?

   Arendt and others (1979) (source 1 of 5)

   Arendt, J.W., and others, 1979, Hydrogeochemical and stream sediment reconnaissance procedures of the Uranium Resource Evaluation project: Union Carbide Corporation, Nuclear Division, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tenn., K/UR-100: GJBX GJBX-32(80), U.S. Department of Energy, Grand Junction, Colorado.

   Type_of_Source_Media: paper

   Butz and others (1979) (source 2 of 5)

   Butz, T.R., and others, 1979, Hydrogeochemical and stream sediment reconnaissance basic data for Ashland NTMS quadrangle, Wisconsin, Michigan, Minnesota: GJBX GJBX-61, U.S. Department of Energy, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tennessee.

   Type_of_Source_Media: paper

   Nichols and others (1978) (source 3 of 5)

   Nichols, C.E., and others, 1978, Hydrogeochemical and stream sediment reconnaissance basic data for Rice Lake NTMS quadrangle, Wisconsin: GJBX GJBX-95(78), U.S. Department of Energy, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tennessee.

   Type_of_Source_Media: paper

   Routledge and others (1981) (source 4 of 5)

   Routledge, R.E., and others, 1981, National Uranium Resource Evaluation, Rice Lake Quadrangle, Wisconsin: GJQ GJQ-006(81), U.S. Department of Energy, Grand Junction, Colorado.

   Type_of_Source_Media: paper

   Routledge (1982) (source 5 of 5)

   Routledge, R.E., 1982, National Uranium Resource Evaluation, Ashland Quadrangle, Wisconsin: FGJ FGJ/F-084(82), U.S. Department of Energy, Grand Junction, Colorado.

   Type_of_Source_Media: paper

2. How were the data generated, processed, and modified?

   (process 1 of 5)

   Sample collection:
   Samples reported in the files of this data set were acquired at several diferrent times using different sampling methods. These are:
   1) Soil samples collected by USGS reported in files A_soil, B_soil, C_soil, E_soil. Samples were collected from shallow pits dug by hand to approximately 0.7 m depth and extended to a final depth of about one meter, where possible, using a bucket auger. Samples were placed into cloth sample bags or sealed plastic bags and air dried in the laboratory before submitting for analyses.
   2) Soil samples collected by USDA Forest Service reported in files A_soil, B_soil, C_soil, E_soil. Samples were collected from hand-dug pits, and in some cases from larger pits dug with a mechanical backhoe. Samples from multiple depths were archived in trays. For the analyses reported here the original samples were divided into representative splits, one of which was submitted for analyses.
   3) NURE stream sediment samples reported in file NURE_original. Techniques of sampling and sample preparation are included in NURE documents (Arendt and others, 1979).
   4) NURE reanalyzed stream sediments reported in file NURE_rean. Original NURE stream sediment samples are archived by the USGS in Lakewood, Colorado. The samples have been stored in glass jars. For reanalysis, the original samples were split into representative portions, one of which was submitted for analyses.
   5) NURE lake sediments reported in file NURE_ls. Lake bottom sediments were collected using a Hornebrook sampler and air dried prior to submission for analyses.
   6) USGS lake sediments reported in file USGS_ls. Lake bottom sediments were collected using a gravity corer in which the sample is recovered in a polyethelene tube. The sample, representing approximately the upper 10 cm of sediment, was recovered by pouring off overlying water and water-sediment slurry, and extruding the remaining sample into a cloth sample bag. Samples were allowed to drip dry in the field and were later air-dried in the laboratory prior to submission for analyses.

   (process 2 of 5)

   Sample preparation:
   Soil samples--The dry soil sample is disaggregated, if necessary, in the mechanical, ceramic mortar and pestle (soil grinder). The sample is sieved to the required grain size of 100 percent minus 80-mesh (<180 mm) and at least 80 percent minus 100-mesh (<150 mm) using sieves with stainless-steel screens. The sieved fraction is pulverized if further reduction in grain size is required by the subsequent chemical analysis.
   USGS_stream sediments--The dry stream-sediment samples are disaggregated by hand, as necessary, and as much organic material as possible is removed. The samples are sieved to pass an 80-mesh screen (<180 mm) or the particle size specified on the RFA. The sieved fraction is generally ground in a mechanical pulverizer, placed in a 3-oz container and mixed to ensure homogeneity.
   NURE analyses--Procedures are described by Arendt and others (1979).

   Data sources used in this process:

   • Arendt and others (1979)

   (process 3 of 5)

   Chemical analysis:
   SAMPLES ANALYZED BY USGS Forty major, minor, and trace elements are determined in geological materials by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The sample is decomposed using a mixture of hydrochloric, nitric, perchloric, and hydrofluoric acids at low temperature. The digested sample is aspirated into the ICP-AES discharge where the elemental emission signal is measured simultaneously for the forty elements. Calibration is performed by standardizing with digested rock reference materials and a series of multi-element solution standards.
   The 40 elements analyzed are listed below with their reporting ranges. For samples containing less than the lower limit of detection, the value reported in the data tables is 0.7 of the reporting limit rounded to the nearest reporting unit.
   

   Element          Concentration Range
   Aluminum,    Al    0.005 - 50%
   Calcium,     Ca    0.005 - 50%
   Iron,        Fe    0.02  - 25%
   Potassium,   K     0.01  - 50%
   Magnesium,   Mg    0.005 -  5%
   Sodium,      Na    0.005 - 50%
   Phosphorous, P     0.005 - 50%
   Titanium,    Ti    0.005 - 25%
   Silver,      Ag    2 -  10,000 ppm
   Arsenic,     As   10 -  50,000 ppm
   Gold,        Au    8 -  50,000 ppm
   Barium,      Ba    1 -  35,000 ppm
   Beryllium,   Be    1 -   5,000 ppm
   Bismuth,     Bi   50 -  50,000 ppm
   Cadmium,     Cd    2 -  25,000 ppm
   Cerium,      Ce    5 -  50,000 ppm
   Cobalt,      Co    2 -  25,000 ppm
   Chromium,    Cr    2 -  25,000 ppm
   Copper,      Cu    2 -  15,000 ppm
   Europium,    Eu    2 -   5,000 ppm
   Gallium,     Ga    4 -  50,000 ppm
   Holmium,     Ho    4 -   5,000 ppm
   Lanthanum,   La    2 -  50,000 ppm
   Lithium,     Li    2 -  50,000 ppm
   Manganese,   Mn    4 -  50,000 ppm
   Molybdenum,  Mo    2 -  50,000 ppm
   Niobium,     Nb    4 -  50,000 ppm
   Neodymium,   Nd    9 -  50,000 ppm
   Nickel,      Ni    3 -  50,000 ppm
   Lead,        Pb    4 -  50,000 ppm
   Scandium,    Sc    2 -  50,000 ppm
   Tin,         Sn   50 -  50,000 ppm
   Strontium,   Sr    2 -  15,000 ppm
   Tantalum,    Ta   40 -  50,000 ppm
   Thorium,     Th    6 -  50,000 ppm
   Uranium,     U   100 - 100,000 ppm
   Vanadium,    V     2 -  30,000 ppm
   Yttrium,     Y     2 -  25,000 ppm
   Ytterbium,   Yb    1 -   5,000 ppm
   Zinc,        Zn    2 -  15,000 ppm
   

   For determination of mercury a 0.1g of sample is digested using a mixture of nitric and hydrochloric acids. Potassium permanganate, sulphuric acid and potassium persulphate are added to the solution, followed by a NaCl-hydroxylamine solution and then the solution is diluted to 25mL. It is mixed thoroughly, allowed to settle and then transferred to the auto sampler rack of the Perkin-Elmer Flow Injection Mercury System, FIMS-100.
   The FIMS-100 is a cold-vapor atomic absorption mercury analyzer, which determines the mercury concentration in a solution after it has been liberated as vapor using stannous chloride reducing agent. The absorption of the sample is measured using a mercury lamp at 253.7nm. The lower reporting limit of 0.02 ppm mercury. Samples containing less than 0.02 ppm are assigned a value of 0.01 in the data tables.
   Arsenic was determined by weighing 0.1 g of sample into a zirconium crucible. Approximately 0.75 g of sodium peroxide is added and mixed. The mixture is heated in a muffle furnace set at 750°C for four minutes. The sample is cooled then 15 ml of water and 5 ml of concentrated HCl is added. The mixture is shaken and 0.25 ml of an ascorbic acid KI solution is added then diluted with 20% HCl and let to stand overnight. Arsenic is then measure using hydride generation atomic absorption spectrometry. The optimum concentration range without sample dilution is 0.6 ppm to 20 ppm.
   Selenium is determined by weighing .25 g of sample into a test tube, adding a mixture of nitric, hydrofluoric and perchloric acids and heating. After the solution is cooled hydrochloric and nitric are added, heated again and cooled. The samples are diluted and analyzed using hydride generation atomic absorption spectrometry. The expected analytical range for selenium is 0.2 to 4 ppm.
   Total carbon is determined by the use of an automated carbon analyzer. A weighed sample is combusted in an oxygen atmosphere at 1370°C to oxidize carbon to carbon dioxide. Moisture and dust are removed and the carbon dioxide gas is measured by a solid state infrared detector.
   Carbonate carbon is determined as carbon dioxide by coulometric titration. The sample is treated with hot 2N perchloric acid and the evolved carbon dioxide is passed into a cell containing a solution of monoethanolamine. The carbon dioxide, quantitatively absorbed by the monoethanolamine, is coulometrically titrated using platinum and silver/potassium-iodide electrodes. The lower reporting limit is 0.01% carbon dioxide and samples containing up to 50% carbon dioxide may be analyzed. Sample size is adjusted from 0.5 g for the range 0.01 to 5% carbon dioxide, 0.1 g for the range 5 to 10% carbon dioxide, and 0.02 g for greater than 10% carbon dioxide
   Organic carbon is calculated as the difference between total carbon and carbonate carbon,
   Total sulfur is determined by using an automated sulfur analyzer. Approximately 0.25 g of sample is mixed with iron chips and LECOCEL and is heated in a combustion tube in a stream of oxygen at high temperature. Sulfur is oxidized to sulfur dioxide. Moisture and dust are removed and the sulfur dioxide gas is then measured by a CS-244 infrared detector.
   SAMPLES ANALYZED BY THE NURE PROGRAM Stream sediments-most elements reported were determined by plasma source emission spectroscopy. As and Se were determined by atomic absorption spectrometry, and U by flourometry. All analyses were done at the Uranium Resource Evaluation Project Laboratory at the Oak Ridge National Laboratory, Oak Ridge, Tennessee. Details of techniques are given in Arendt and others (1790).
   The elements analyzed and their lower limits of detection in parts per million are:

   U   0.25
   As  0.1
   Se  0.1
   Ag  2
   Al  0.05%
   B  10
   Ba  2
   Be  1
   Ca  0.05%
   Co  4
   Cr  1
   Cu  2
   Fe  0.05%
   Li  1
   Mg  0.05%
   Mn  4
   Mo  4
   Na  0.05%
   Nb  4
   Ni  2
   P   5
   Sc  1
   Th  2
   Ti 10
   V   2
   Y   1
   Zn  2
   Zr  2
   

   (process 4 of 5)

   Recalculation of NURE stream sediment analyses (file NURE_adj)--Comparison of 400 sets of original NURE stream sediment analyses, performed in 1978-79, and USGS reanalysis of the same samples, performed in 1998-1999, shows significant and consistent variations for most elements between the two data sets. Using those consistent variations we have derived formulas to recalculate the original NURE data to be consistent with the USGS analyses. Plotting NURE values vs. USGS values produces regression lines whose slope generally varies significantly from 1 for most elements. A correction factor, which changes to slope to 1, was determined and then applied to all 913 NURE analyses. The resulting adjusted values are believed to be more accurate than the original NURE data and remove an apparent quadrangle bias that exists for some elements in the original data. Visual inspection of spatial patterns of the original NURE data show an apparent discontinuity of concentrations along the boundary between the Rice Lake and Ashland Quadrangles which is not present in the recalculated values.

   (process 5 of 5)

   Compile dbf of sample locations and chemical analysis results

3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?

   USGS ANALYSES-- This report pertains to samples analyzed by the U.S. Geological Survey and includes all analyses contained in the data files A_soil, B_soil, C_soil, E_soil, USGS_ls, and NURE_rean. Analytical results were compared to results for standard reference materials. Data quality checks were performed both at an analytical laboratory (XRAL) and by the USGS. The first level of quality control checks occurred at XRAL. XRAL Laboratories is accredited to the ISO 9002, 1994 standard (ANSI-RAB 01298 and NACB 9555). The laboratory's quality control protocol is to insert a reagent blank and a reference sample material with every batch of 20 samples to measure the analytical accuracy. Duplicate samples are analyzed at the end of the sample set to measure analytical variance as well as sample variance. Data passing the quality control criteria was sent to the USGS and imported into the Laboratory Information Management System (LIMS).
   The second level of data validation was performed at the USGS. All samples submitted to XRAL are accompanied with a set of USGS in-house reference samples submitted at the rate of 10%. Using a program within the LIMS, the data for the reference samples was evaluated by comparing the "obtained" analytical value to the "expected" value for each element. The values must fall within the range of acceptance, which varies between +/- 5% to +/-20% depending on the analytical method.
   NURE ANALYSES-- This report pertains to samples collected and analyzed by the NURE Program and includes all analyses contained in the files NURE_original and NURE_ls. All analyses of stream sediments were performed at Oak Ridge National Laboratory, mostly by Plasma Source Emission Spectroscopy. Control samples consisting of two batches of samples were submitted daily along with field samples. A statistical summary of quality control results and analytical procedures and accuracy is given in the NURE reports for the Ashland Quadrangle (GJBX-61) and the Rice Lake Quadrangle (GJBX-95).
   Analyses of NURE lake sediment samples were performed at Rocky Mountain Geochemical Corporation in Sparks, Nevada, but information on analytical and quality control procedures was not specified in the original reports.

2. How accurate are the geographic locations?

   USGS sample sites were located using a GPS instrument. Maximum observed variation in repeated GPS readings taken at the same site is in the fourth decimal place (0.000x degree) and estimated positional accuracy is approximately +/- 50 meters.
   For samples collected by the NURE Program latitude-longitude coordinates were reported in the original data files, as decimal degrees, to only 3 decimal places. Therefore, the precision of these coordinates is limited to +/- 0.001 degrees or +/- 3.6 seconds. This translates to a minimum precision of +/- 365 feet (111 m) for latitude values and between +/- 259 feet (79 m) to +/- 235 feet (72 m) for longitude values (calculated at latitudes of 45° and 50°N, respectively.)
   The technique for locating NURE lake sediment sample sites is not specified in the original NURE reports. We infer it to have been an approximation of the location based on visual examination of topography as indicated on topographic maps or aerial photographs and likely to be accurate to within roughly 100-200 meters. Locations were provided only as large-scale maps showing sample sites. We have derived the locations in the present report by digitizing locations from those maps.
   Soil sample sites collected by USDA Forest Service were initially recorded on aerial photographs and then transferred to 1:24,000 topographic maps by visually comparing features identifiable on both. Latitude and Longitude coordinates were read from the maps by hand using appropriate graticules. Estimated accuracy is +/- 100m.

3. How accurate are the heights or depths?

4. Where are the gaps in the data? What is missing?

   Analytical results are presented for nearly all elements in the samples. Where an analysis was not performed, large negative values such as -999 or -9999 (for integer fields) or -9999.9 (for real number fields) is given in the data set, and that these comprise a small proportion (less than 5% of samples overall) of available data.
   The only analysis which has significant missing data is Vanadium oxide from the NURE lake-bottom sediments, which has 204 missing of 361 analyses.

5. How consistent are the relationships among the observations, including topology?

   The data reported here come from two different sampling programs. Reconciling inconsistencies in the analytical results was part of the study process, and some of the original NURE stream sediment samples were reanalyzed in order to determine if a correction would be needed to make fair comparisons between the original analyses and USGS studies. Such adjustments were made to the data reported here.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: none

Use_Constraints:

Any hardcopies utilizing these data sets shall clearly indicate their source. If the user has modified the data in any way they are obligated to describe the type of modification they have performed. User specifically agrees not to misrepresent these data sets, nor to imply that changes they have made were approved by the U.S Geological Survey.

Who wrote the metadata?

Dates:

Last modified: 15-Jan-2003

Metadata author:

William F Cannon
U.S. Geological Survey, Mail Stop 954
12201 Sunrise Valley Drive
Reston, VA 20192
USA

703-648-6345 (voice)
703-648-6383 (FAX)
wcannon@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)