Geophysical survey results using GEM2 earth conductivity meter in the Park Falls Unit of the Chequamegon-Nicolet National Forest, Wisconsin
Metadata also available as
Metadata:
- Identification_Information:
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- Citation:
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- Citation_Information:
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- Originator: Wisconsin Geological and Natural History Survey (WGNHS)
- Publication_Date: 20181228
- Title:
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Geophysical survey results using GEM2 earth conductivity meter in the Park Falls Unit of the Chequamegon-Nicolet National Forest, Wisconsin
- Geospatial_Data_Presentation_Form: vector digital data
- Description:
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- Abstract:
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A geophysical survey was conducted to confirm locations of near-surface bedrock near the intersection of Gates Lake Road and Forest Road 137 in the Park Falls Unit of the CNNF during the summer of 2011. The survey was conducted using the EM31 and EM34 conductivity meters manufactured by Geonics Limited and the GEM2 earth conductivity meter manufactured by Terraplus. Both instruments output results of apparent conductivity in millisiemens per meter (mS/m). This dataset presents the results of the GEM2 conductivity meter.
The following are from the Terraplus website:
“A new broadband electromagnetic sensor, GEM-2, is a hand-held, digital, multi-frequency sensor. The GEM-2 operates in a frequency range of about 300 Hz to 24 kHz, and can transmit an arbitrary waveform containing multiple frequencies. The unit is capable of transmitting and receiving any digitally-synthesized waveform by means of the pulse-width modulation technique. Owing to the arbitrary nature of its broadcast waveform and high-speed digitization, the sensor can operate either in a frequency-domain mode or in a time-domain mode.
Depth of exploration for a given earth medium is determined by the operating frequency. Therefore, measuring the earth response at multiple frequencies is equivalent to measuring the earth response from multiple depths. Hence, such data can be used to image a 3-D distribution of subsurface objects.”
(<http://terraplus.ca/products/electromagnetics/gem2.aspx>)
Survey results and interpretation are documented in an accompanying summary report available from the Wisconsin Geological and Natural History Survey.
- Purpose:
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This dataset was produced as part of a project to assess groundwater resources across the Chequamegon-Nicolet National Forest. Groundwater is an important resource for the forest, and a more comprehensive understanding of this resource can help guide land management decisions.
Geophysical surveys evaluate changes in ground conductivity and therefore can be used to confirm areas of shallow bedrock. Knowledge of bedrock outcrops helps to constrain interpretations of the bedrock surface, which is important for developing a conceptual framework for the hydrogeologic system.
The datasets produced as part of this project are divided by location into four groups, corresponding to the four main National Forest Units: Medford, Nicolet, Park Falls, and Washburn/Great Divide. This dataset is located in the Park Falls Unit.
- Time_Period_of_Content:
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- Time_Period_Information:
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- Single_Date/Time:
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- Calendar_Date: 20181228
- Currentness_Reference: publication date
- Status:
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- Progress: Complete
- Maintenance_and_Update_Frequency: None planned
- Spatial_Domain:
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- Bounding_Coordinates:
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- West_Bounding_Coordinate: -99.420614
- East_Bounding_Coordinate: -90.186386
- North_Bounding_Coordinate: 45.860333
- South_Bounding_Coordinate: 0.000000
- Keywords:
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- Theme:
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- Theme_Keyword_Thesaurus: None
- Theme_Keyword: Park Falls Unit
- Theme_Keyword: Price County
- Theme_Keyword: Vilas County
- Theme_Keyword: geology
- Theme_Keyword: geologic
- Theme_Keyword: geophysics
- Theme_Keyword: bedrock
- Theme_Keyword: Wisconsin
- Place:
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- Place_Keyword_Thesaurus: None
- Place_Keyword: Chequamegon-Nicolet National Forest
- Place_Keyword: Park Falls
- Place_Keyword: Price County
- Place_Keyword: Vilas County
- Place_Keyword: Wisconsin
- Access_Constraints: None
- Use_Constraints:
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These data are provided by the Wisconsin Geological and Natural History Survey (WGNHS) on an "as is" basis. WGNHS will not be liable for any damages of any kind arising from the use of these data, including, but not limited to direct, indirect, punitive, and consequential. WGNHS makes no warranties on these data, express, implied, statutory, or in any other provision of any agreement or communication, and specifically disclaims any implied warranties of merchantability or fitness for a particular purpose.
- Point_of_Contact:
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- Contact_Information:
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- Contact_Organization_Primary:
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- Contact_Organization: Wisconsin Geological and Natural History Survey (WGNHS)
- Contact_Position: Information Manager
- Contact_Address:
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- Address_Type: unknown
- Address: 3817 Mineral Point Rd
- City: Madison
- State_or_Province: Wisconsin
- Postal_Code: 53705-5100
- Country: USA
- Contact_Electronic_Mail_Address: gis@wgnhs.uwex.edu
- Data_Set_Credit:
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This project was funded by the U.S. Forest Service. The data analysis was completed by the Wisconsin Geological and Natural History Survey (WGNHS) in 2011.
- Native_Data_Set_Environment: Version 6.2 (Build 9200) ; Esri ArcGIS 10.6.0.8321
- Data_Quality_Information:
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- Completeness_Report:
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This dataset provides GEM2 geophysical survey results measured in the field. See the product website for information on equipment resolution, accuracy, and use limitations:
<http://terraplus.ca/products/electromagnetics/gem2.aspx>
The frequency of 63030 Hz is higher than what is generally used with this instrument. The lower frequencies did not match the EM31 results as well; these data are intended to serve as a confirmation for the EM31 measurements.
The geophysical survey interpretation is documented in an accompanying summary report available from the Wisconsin Geological and Natural History Survey.
- Lineage:
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- Source_Information:
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- Source_Contribution:
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This dataset consists of point data from a geophysical survey with a GEM2 conductivity meter in the Park Falls Unit of the Chequamegon-Nicolet National Forest in Wisconsin. The methodology and results are documented in an accompanying summary report available from WGNHS.
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- Map_Projection_Name: NAD 1983 UTM Zone 15N
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- Attribute:
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- Attribute_Label: EC63030Hz_
- Overview_Description:
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- Entity_and_Attribute_Overview:
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EC63030HZ_: The apparent conductivity in millisiemens per meter (mS/m).
- Entity_and_Attribute_Detail_Citation:
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This dataset consists of point data from a geophysical survey with a GEM2 conductivity meter in the Park Falls Unit of the Chequamegon-Nicolet National Forest in Wisconsin. The methodology and results are documented in an accompanying summary report available from WGNHS.
- Metadata_Reference_Information:
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- Metadata_Date: 20190212
- Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
- Metadata_Standard_Version: FGDC-STD-001-1998
- Metadata_Time_Convention: local time
Generated by mp version 2.9.12 on Tue Feb 12 11:26:44 2019