Processed Continuous Resistivity Profiles from Cape Cod National Seashore, Feb. 28, 2006

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Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: John F. Bratton
Publication_Date: 2008
Title:
Processed Continuous Resistivity Profiles from Cape Cod National Seashore, Feb. 28, 2006
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2006-1169
Publication_Information:
Publication_Place: Woods Hole Science Center, Woods Hole, MA
Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Online_Linkage:
<http://pubs.usgs.gov/of/2006/1169/data/res_data/2006/proc_resis/feb28_proc.zip>
Online_Linkage: <http://pubs.usgs.gov/of/2006/1169/htmldocs/catalog.htm>
Larger_Work_Citation:
Citation_Information:
Originator: VeeAnn A. Cross
Originator: John F. Bratton
Originator: John Crusius
Originator: John A. Colman
Originator: Timothy D. McCobb
Publication_Date: 2008
Title: Submarine Hydrogeological Data from Cape Cod National Seashore
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2006-1169
Publication_Information:
Publication_Place: Woods Hole Science Center, Woods Hole, MA
Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Online_Linkage: <http://pubs.usgs.gov/of/2006/1169/>
Description:
Abstract:
Continuous resistivity profiling (CRP) surveys were conducted at Cape Cod National Seashore in 2004 and 2006 in order to test hypotheses about groundwater flow under and into estuaries and the Atlantic Ocean. Coastal resource managers here and elsewhere are concerned about nutrients that are entering coastal waters via submarine groundwater discharge, which are contributing to eutrophication and harmful algal blooms. CRP is used to measure electrical resistivity of sediments, a property that is sensitive to differences in salinity of submarine ground water. The 2004 and 2006 surveys used floating resistivity streamers of 100 m and 50 m respectively. The depth penetration of the streamers is approximately 20% of the streamer length which translates to approximately 20-25 m with the 100 m streamer and 12-14 m with the 50 m streamer. These data were processed using AGI's EarthImager 2D software.
Purpose:
To provide resistivity data as collected by the AGI SuperSting system and processed with EarthImager software.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20060228
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -69.973172
East_Bounding_Coordinate: -69.945350
North_Bounding_Coordinate: 41.836933
South_Bounding_Coordinate: 41.820967
Keywords:
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: CMGP
Theme_Keyword: Coastal and Marine Geology Program
Theme_Keyword: Continuous Resistivity Profiling
Theme_Keyword: CRP
Theme_Keyword: ground-water
Theme_Keyword: OF 2006-1169
Theme_Keyword: Open-File Report
Theme_Keyword: submarine ground-water
Theme_Keyword: U.S. Geological Survey
Theme_Keyword: USGS
Theme_Keyword: Woods Hole Science Center
Theme_Keyword: WHSC field activity serial number 06007
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: geoscientificInformation
Theme_Keyword: inlandWaters
Theme_Keyword: location
Theme_Keyword: oceans
Place:
Place_Keyword_Thesaurus: General
Place_Keyword: Atlantic Ocean
Place_Keyword: Cape Cod
Place_Keyword: Massachusetts
Place_Keyword: North America
Place_Keyword: United States
Place_Keyword: Salt Pond
Place_Keyword: Nauset Marsh
Access_Constraints: None.
Use_Constraints:
The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: John F. Bratton
Contact_Organization: U.S. Geological Survey
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2254
Contact_Facsimile_Telephone: 508-457-2210
Contact_Electronic_Mail_Address: jbratton@usgs.gov
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780
Data_Quality_Information:
Completeness_Report:
Only those lines with valid resistivity data are represented here.
Lineage:
Source_Information:
Source_Contribution:
These data were acquired with an AGI SuperSting Marine system that is described at the website: www.agiusa.com/marinesystem.shtml. The particular system used for this acquisition was an 11 electrode array with electrodes spaced 5 meters apart. The potential electrodes are made of graphite, with the remaining electrodes stainless steel. A dipole-dipole configuration was used for the data collection in which two fixed current electrodes are assigned with the measurement of voltage potentials between electrode pairs in the remaining electrodes. Each line of data acquisition records several files. The two files necessary for processing are the *.stg and *.gps file. The STG file contains the resistivity data, while the GPS file contains the navigation information including bathymetry. GPS and bathymetry data acquired with a Lowrance system.
Process_Step:
Process_Description:
The data were transferred from the logging computer via AGISSAdmin software. The data files available for this day are l1*, l2*, l3*, l4*, l5*, l6*, l8*, l9*, l10*, l11*, l12*, l13*, l14*, and l15*. ***Of note, on lines 1 and 2, during acquisition the distance between the cable connection point and the first electrode was entered as 10 meters instead of -10 meters. This can be adjusted when reading the data into Marine Log Manager for linearization.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
$GPRMC lines with the GPS file that had bad time stamps or were otherwise corrupt were deleted.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The resistivity data were merged with the navigation data and linearized using AGI's Marine Log Manager software. (Note that the Marine Log Manager version is different than the software version of the AGISSAdmin software of which it is a part - although shipped together, the software is developed separately). In some instances, only a portion of the line was exported for processing. In particular, turns are removed before processing. (AGISSAdmin version 1.33.182) ***Note. When reading in l1 and l2, the GPS offset needs to be set to 10 to account for an incorrect acquisition parameter indicating the distance between the cable connection point and the first electrode.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
In most cases, nearshore values were very important. For that reason, the whole linearized STG file was selected for export. This applied in the following lines: l1, l2, l4, l5, l6, l9, l11, l12 and l14. The way the Marine Log Manager software works, the first value exported is where at least one of the electrodes has a known navigational fix. But the rest of the streamer electrodes at this position have a negative distance along line. When this export option is chosen, no DEP file is output. In order to create a DEP file, a second export file is needed. This one selects only positive electrode positions for export.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The linearized STG file with negative values is processed with EarthImager version 2.01 in order to determine the most negative position (available from the final XYZ output file). Once this is done, I can create a navigation fix for that negative distance along line. Based on the trackline created from the GPS data, I run an ArcView 3.3 avenue script (extendline.ave) which uses a straight-line tow path assumption of the first 2 points to create an additional point at the negative distance input. Essentially I extend the line at the start of the line.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
With this new point I can modify the DEP file generated by the positive only electrode position export. I add in the negative distance along, as well as all the supplemental information, including the header information describing the latitude and longitude position of the start of line. So now I have a linearized STG file, as well as the accompanying DEP file for those files with negative distances along line.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The DEP file was checked for anomalous bathymetry values, or duplicated distance along values, and those lines in the file were deleted.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
EarthImager software does not require that a default resistivity value for the water column be supplied in the DEP file. If one is not supplied, then it calculates a value based on the first electrode pair. On this survey, an instrument was used periodically to measure water conductivity. This value was converted to appropriate resistivity units and added to the DEP file. A value of 0.2 was used in all the files.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
EarthImager version 2.0.1 was used to process the data files. The *.ini file accompanying the results contains the parameters used during the processing. These parameters include: minimum voltage: 0.02; minimum abs(V/I): 2E-5; max repeat error: 3%; min apparent res: 0.03; max apparent res: 1000; max reciprocal error: 5%; remove spikes, smooth model inversion; finite element method; Cholesky decomposition; Dirichlet boundary condition; thickness incremental factor: 1.1; depth factor: 1.1; number of iterations: 8; stop criteria: max RMS 3%; error reduction 6%; L2Norm; CRP processing using a 60% overlap.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The results of the processing are JPEG images of the resistivity profile (a short and extended version); an XYZ file containing the distance along, depth, apparent resistivity (ohm-m); an LLT file which contains longitude, latitude, depth, and resistivity value; a UTM file which contains easting, northing, depth, resistivity value. The JPEG files produced uses a color scale that is based on the data from that particular file. This particular version of EarthImager defaults to using the latitude and longitude values along the x-axis to mark electrode positions. Another pair of long and short JPEG images was exported which use the distance along values for the electrode positions on the X-axis.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The XYZ output file was then loaded into Matlab, along with the depth information, to create a new JPEG image with the same color scale for all the data files. In this manner, the JPEG images can be compared directly. Care was taken to try to get the vertical and horizontal scales uniform as well, although this was not always possible due to Matlab limitations. These images reside in the "matlabimages" folder.
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
The XYZ output file was also loaded into Matlab with the DEP file so that those resistivity values in the water column could be removed. The extrapolated value at the sediment water interface was exported, as well as all the values in the original XYZ file below the DEP line. These new XYZ files are in the folder "trimxyz".
Process_Date: 2006
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: John F. Bratton
Contact_Organization: U.S. Geological Survey
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2254
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: jbratton@usgs.gov
Resource_Description: Downloadable Data
Distribution_Liability:
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: AGI
File_Decompression_Technique: WinZip
Transfer_Size: 17.8
Fees: None.
Technical_Prerequisites:
These data are available in a format compatible with AGI Geosciences EarthImager software, as well as summary images in JPEG format. The user must have software capable of reading the AGI format, or software capable of viewing JPEG images.
Metadata_Reference_Information:
Metadata_Date: 20080225
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: VeeAnn A. Cross
Contact_Organization: U.S. Geological Survey
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: (508) 548-8700 x2251
Contact_Facsimile_Telephone: (508) 457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: <http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
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