Processed continuous resistivity profiling data collected in the Indian River Bay, Delaware, on April 15, 2010, on U.S. Geological Survey Field Activity 2010-006-FA

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Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: John F. Bratton
Originator: VeeAnn A. Cross
Publication_Date: 2014
Title:
Processed continuous resistivity profiling data collected in the Indian River Bay, Delaware, on April 15, 2010, on U.S. Geological Survey Field Activity 2010-006-FA
Edition: 1
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2011-1039
Publication_Information:
Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA
Publisher: U.S. Geological Survey, Coastal and Marine Geology Program
Online_Linkage:
<http://pubs.usgs.gov/of/2011/1039/data/resistivity/proc_resis/apr15_proc.zip>
Online_Linkage:
<http://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html>
Larger_Work_Citation:
Citation_Information:
Originator: V.A. Cross
Originator: J.F. Bratton
Originator: H.A. Michael
Originator: K.D. Kroeger
Originator: A. Green
Originator: E. Bergeron
Publication_Date: 2014
Title:
Continuous Resistivity Profiling and Seismic-Reflection Data Collected in April 2010 from Indian River Bay, Delaware
Edition: 1
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2011-1039
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Online_Linkage: <http://pubs.usgs.gov/of/2011/1039/>
Online_Linkage: <http://dx.doi.org/10.3133/ofr20111039>
Description:
Abstract:
A geophysical survey to delineate the fresh-saline groundwater interface and associated sub-bottom sedimentary structures beneath Indian River Bay, Delaware, was carried out in April 2010. This included surveying at higher spatial resolution in the vicinity of a study site at Holts Landing, where intensive onshore and offshore studies were subsequently completed. The total length of continuous resistivity profiling (CRP) survey lines was 145 kilometers (km), with 36 km of chirp seismic lines surveyed around the perimeter of the bay. Medium-resolution CRP surveying was performed using a 50-meter streamer in a bay-wide grid. Results of the surveying and data inversion showed the presence of many buried paleochannels beneath Indian River Bay that generally extended perpendicular from the shoreline in areas of modern tributaries, tidal creeks, and marshes. An especially wide and deep paleochannel system was imaged in the southeastern part of the bay near White Creek. Many paleochannels also had high-resistivity anomalies corresponding to low-salinity groundwater plumes associated with them, likely due to the presence of fine-grained estuarine mud and peats in the channel fills that act as submarine confining units. Where present, these units allow plumes of low-salinity groundwater that was recharged onshore to move beyond the shoreline, creating a complex fresh-saline groundwater interface in the subsurface. The properties of this interface are important considerations in construction of accurate coastal groundwater flow models. These models are required to help predict how nutrient-rich groundwater, recharged in agricultural watersheds such as this one, makes its way into coastal bays and impacts surface water quality and estuarine ecosystems. For more information on the survey conducted for this project, see <http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2010-006-FA>.
Purpose:
This dataset provides the processed continuous resistivity profile (CRP) data collected on April 15, 2010 in the Indian River Bay, Delaware by the AGI SuperSting system and acts as an archive of these data. The CRP system images the subsurface electrical properties of an estuarine, riverine or lacustrine environment. Resistivity differences can be attributed to subsurface geology (conductive vs less conductive layers) and hydrogeologic conditions with fresh water exhibiting high resistivity and saline conditions showing low resistivity.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20100415
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -75.190433
East_Bounding_Coordinate: -75.076000
North_Bounding_Coordinate: 38.620000
South_Bounding_Coordinate: 38.576217
Keywords:
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: U.S. Geological Survey
Theme_Keyword: USGS
Theme_Keyword: Coastal and Marine Geology Program
Theme_Keyword: CMGP
Theme_Keyword: Woods Hole Coastal and Marine Science Center
Theme_Keyword: WHCMSC
Theme_Keyword: Field Activity Number 2010-006-FA
Theme_Keyword: Info Bank ID K-6-10-DL
Theme_Keyword: navigation
Theme_Keyword: bathymetry
Theme_Keyword: water temperature
Theme_Keyword: continuous resistivity profiling
Theme_Keyword: CRP
Theme_Keyword: R/V Knob
Theme_Keyword: AGI SuperSting
Theme_Keyword: processed data
Theme_Keyword: groundwater
Theme_Keyword: submarine groundwater
Theme_Keyword: Open-file Report 2011-1039
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: elevation
Theme_Keyword: location
Theme_Keyword: oceans
Theme_Keyword: oceans and estuaries
Theme_Keyword: oceans and coastal
Theme_Keyword: geoscientificInformation
Place:
Place_Keyword_Thesaurus: General
Place_Keyword: North America
Place_Keyword: North Atlantic Ocean
Place_Keyword: United States
Place_Keyword: Delaware
Place_Keyword: Indian River Bay
Place_Keyword: Indian River Inlet
Place_Keyword: Holts Landing
Place_Keyword: Piney Neck
Place_Keyword: Rosedale Beach
Access_Constraints: None.
Use_Constraints:
The public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
Point_of_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: Woods Hole Coastal and Marine Science Center
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
Native_Data_Set_Environment:
Microsoft Windows Vista Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 9.3.1.4095
Cross_Reference:
Citation_Information:
Originator: Advanced Geosciences, Inc.
Publication_Date: 2003
Title:
Instruction Manual for the Marine Log Manager Module of the Administrator for SuperSting Software, Release 1.3.7
Publication_Information:
Publication_Place: Austin, TX
Publisher: Advanced Geosciences, Inc.
Online_Linkage: <http://www.agiusa.com/>
Cross_Reference:
Citation_Information:
Originator: Advanced Geosciences, Inc.
Publication_Date: 2008
Title:
Instruction Manual for EarthImager 2D, version 2.2.8, Resistivity and IP inversion software
Publication_Information:
Publication_Place: Austin, TX
Publisher: Advanced Geosciences, Inc.
Online_Linkage: <http://www.agiusa.com/>
Data_Quality_Information:
Completeness_Report:
All usable data collected on this day were processed. The processed files are included in this dataset. The apparent gaps in the filenames represent skipped filenames - no data were collected on those lines. The apparent gaps are: L20F1, L34F1, L37F1, and L46F1.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The navigation system used was a Lowrance 480M with an LGC-2000 Global Positioning System (GPS) antenna. The antenna was located directly above the fathometer transducer mount point, but offset to the starboard by 2 meters from the resistivity streamer tow point. GPS data are assumed to be accurate wtihin 10 meters on this survey.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
All bathymetry values were acquired by the 200 kHz Lowrance fathometer. The fathometer was mounted on the starboard side of the R/V Knob, directly below the GPS antenna. The Lowrance manufacturer indicates the speed of sound used by the system to calculate depth is 4800 feet/second. The depth values are not corrected for the approximately 0.2 m transducer draft. All depth values are assumed to be accurate to within 1 meter.
Lineage:
Source_Information:
Source_Contribution:
The continuous resistivity profile (CRP) system used on this cruise was an AGI SuperSting marine system described at the website: www.agiusa.com/marinesystem.shtml. The particular system used for this acquisition was a 50-m streamer with an 11 electrode array with electrodes spaced 5 meters apart. The source electrodes are graphite, while the receiver electrodes are 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 potential between electrode pairs in the remaining electrodes. The maximum depth below the water surface the streamer can reach is approximately 1/4 the streamer length. So for the 50-m streamer, maximum depth is about 12.5 meters. Each line of data acquisition records several files. The two files necessary for processing are the *.stg and the *.gps file. The STG file contains the resistivity data, while the GPS file contains the navigation information. The navigation system used in concert with the CRP system is a Lowrance LMS-480M with an LGC-2000 GPS antenna and a 200 kHz fathometer transducer. The antenna and fathometer transducer were mounted on the starboard side of the boat. The streamer tow point was on the port side aft. The layback offset between the navigation antenna and the first electrode was 17.6 meters on April 13 and 14. On April 15 the antenna and transducer were moved 1.6 m aft changing the layback offset to 16 m. This layback offset is accounted for by the acquisition system. The approximately 2 m lateral offset is not accounted for. The Lowrance transducer also contains a temperature sensor. Lowrance indicates the speed of sound used by the system is 4800 feet/second. Both the temperature and depth information are recorded in the logged GPS file. There are instances where no depth or temperature information is recorded due to an equipment problem. The CRP system images the subsurface electrical properties of an estuarine, riverine or lacustrine environment. Resistivity differences can be attributed to subsurface geology (conductive vs less conductive layers) and hydrogeologic conditions with fresh water exhibiting high resistivity and saline conditions showing low resistivity.
Process_Step:
Process_Description:
Once the navigation and raw data were assessed to be okay, the actual processing of the resistivity data could start. Of note, see the metadata for jd105gps_bestdepth.shp (available at <http://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html>) for a description of the work needed to extract valid bathymetry values for use in the data processing. The resistivity data were merged with the navigation data and linearized using AGI's Marine Log Manager (MLM) 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). The GPS files used are the "newgps" files that have been modified to include best available bathymetry values. The version of Marine Log Manager used was AGI SSAdmin MLM v 1.3.4.217 The GPS offset was set to 0 meters since the offset (16 meters) between the navigation antenna and the first electrode of the resistivity streamer was accounted for in an acquisition offset. Lateral offset is not accounted for. The lines processed on this day are L20F2, L21F1, L22F1, L23F1, L24F1, L25F1, L26F1, L26F2, L27F1, L28F1, L29F1, L30F1, L31F1, L32F1, L33F1, L35F1, L36F1, L37F2, L38F1, L39F1, L40F1, L41F1, L42F1, L43F1, L44F1, L45F1, L46F2, L47F1, L48F1, L49F1, and L50F1. One line was split during the MLM processing due to a sharp turn in the line. Line L36F1 was split into L36F1_a and L36F1_b. These line names are what the * refers to in the source used and source produced citations. This process step and all subsequent process steps were performed by the same person - VeeAnn A. Cross.
Source_Used_Citation_Abbreviation: *newgps.gps
Source_Used_Citation_Abbreviation: *.stg
Process_Date: 201005
Source_Produced_Citation_Abbreviation: *lin.stg
Source_Produced_Citation_Abbreviation: *lin.dep
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: Woods Hole Coastal and Marine Science Center
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:
Each DEP file was checked for anomalous bathymetry values, or duplicated distance along values, and those lines in the file were deleted.
Source_Used_Citation_Abbreviation: *.dep
Process_Date: 201005
Source_Produced_Citation_Abbreviation: *.dep
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 additional instrument was deployed to measure water temperature and salinity. This instrument was a YSI 600XLM mounted just behind the GPS/fathometer. See the YSI metadata (available at <http://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html>) for details on the processing of the YSI data. An average water resistivity value was calculated based on the YSI measurements during the time of collection of a given line of resistivity data collection. Note that the recorded YSI times are local times, while the CRP records UTC time. During this cruise, UTC is +4 hours compared to local time. This average resistivity value varied for each data file. The calculated value was added to the appropriate place in the DEP files so that a known water resistivity value would be used in the resistivity inversion calculations. These files were saved with a new filename with "wres" appended to the prefix of the filename indicating a water resistivity value is in the header of the file.
Source_Used_Citation_Abbreviation: *.dep
Process_Date: 201009
Source_Produced_Citation_Abbreviation: *wres.dep
Process_Step:
Process_Description:
EarthImager version 2.2.8 build 562 was then used to process the data files. The process settings were set to CRP - Saltwater. The *.ini file accompanying the results contains the parameters used during 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 negative resistivity, smooth model inversion; finite element method; Cholesky decomposition; Dirichlet boundary condition; thickness incremental factor: 1.1; depth factor: 1.1; max number of CG iterations: 100; stop criteria: number of iterations 8; max RMS 3%; error reduction 5%; L2Norm; CRP processing using a 65% overlap. These INI files can be loaded in EarthImager to help maintain consistent processing parameters for other datasets. When the files are processed, numerous files are generated. Because of the "roll-along" nature of the processing, each line takes several iterations of processing which are then combined into a single output. The output consists of numerous files including JPEG images and text files representing the XYZ position of each resistivity value. There are four JPEG images generated with each process when possible - a long version with the x-axis labeled with distance along line (in meters) and a corresponding short version of the same information. Additionally, there is a long version with the x-axis labeled with latitudes and longitudes and the corresponding short version with the same information. The JPEG files produced use a color scale for the resistivity that is based on the data extent from that particular file. The JPEG images also include a plot of temperature along the line. In addition to the JPEG images, there are text files with the extensions of *.llt, and *.xyz. Each of these is a text file. The LLT file has four columns of information: longitude in decimal degrees, latitude in decimal degrees, depth in meters, and resistivity value in ohm-m. The XYZ file has three columns of information: distance along line in meters, depth in meters, and resistivity value in ohm-m. There is also a file created with a UTM extension which has the same format as the LLT file except it contains the coordinates in UTM eastings and northings in the zone appropriate for the survey line (software determined). This file was not checked for accuracy as software versions in the past gave erroneous UTM fixes. An example of the file naming convention is as follows: For input files of L3F1_lin.stg and L3F1_lin_wres.dep the resulting series of output files are: L3F1_lin1_trial1.ini; L3F1_lin_AllInvRes.llt; L3F1_lin_AllInvRes.xyz; L3F1_lin_trial1_InvResLong.jpg; L3F1_lin_trial1_InvResShort.jpg. The JPEG images with distance along lines along the X-axis are L3F1_lin_trial1_InvResLong_linear.jpg and L3F1_lin_trial1_InvResShort_linear.jpg. You can process an individual line as many times as you want and the software places the results in incrementing folder names starting with trial1. These data represent trial3 and trial4, which is the processing with the single averaged water resistivity value. The DEP file used in processing is also written to the results folder. One file (L26F1) was extremely short and therefore no "roll-along" processing was required. In these cases, the JPEG images and the XYZ data have to be saved manually. First, just the inverted resistivity line is displayed using View - Inverted Resistivity Section. Then the image can be saved using File - Save Image. And finally, the XYZ data had to be saved manually using File - Save Data in XYZ format. The XYZ output file extension is DAT instead of XYZ. Although temperature was recorded during acquisition, the JPEG plot does not show the temperature profile in the short data files.
Source_Used_Citation_Abbreviation: *lin.stg
Source_Used_Citation_Abbreviation: *lin_wres.dep
Process_Date: 201009
Source_Produced_Citation_Abbreviation: *.ini
Source_Produced_Citation_Abbreviation: *.llt
Source_Produced_Citation_Abbreviation: *.utm
Source_Produced_Citation_Abbreviation: *.xyz or *.dat
Source_Produced_Citation_Abbreviation: *.jpg
Process_Step:
Process_Description:
The XYZ output file was then loaded into MATLAB version 7.5.0.342 (R2007b), along with the depth information from the DEP file, 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. These JPEG images include a black line within the resistivity profile which represents the sediment water interface based on the depth values from the DEP file. The local MATLAB script used to load the data was cp_ir_50m.m, while the local MATLAB script used to export the JPEG image was exportfig.m.
Source_Used_Citation_Abbreviation: *.xyz or *.dat
Source_Used_Citation_Abbreviation: *wres.dep
Process_Date: 201102
Source_Produced_Citation_Abbreviation: matlabimages/*.jpg
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Point
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0.000001
Longitude_Resolution: 0.000001
Geographic_Coordinate_Units: Decimal degrees
Geodetic_Model:
Horizontal_Datum_Name: D_WGS_1984
Ellipsoid_Name: WGS_1984
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257224
Vertical_Coordinate_System_Definition:
Depth_System_Definition:
Depth_Datum_Name: Local surface
Depth_Resolution: 0.1
Depth_Distance_Units: meters
Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
Distribution_Information:
Distributor:
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: Woods Hole Coastal and Marine Science Center
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
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: ASCII
Format_Information_Content:
The WinZip (v. 14) file contains all the processed CRP data from April 15, 2010 as well as the associated metadata files.
Transfer_Size: 72.8 MB
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
<http://pubs.usgs.gov/of/2011/1039/data/resistivity/proc_resis/apr15_proc.zip>
Network_Resource_Name:
<http://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html>
Network_Resource_Name: <http://dx.doi.org/10.3133/ofr20111039>
Fees: None.
Technical_Prerequisites:
The user must have software capable of uncompressing the zip file.
Metadata_Reference_Information:
Metadata_Date: 20140630
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: Woods Hole Coastal and Marine Science Center
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
Generated by mp version 2.9.6 on Mon Jun 30 16:14:40 2014