2006060712110300FALSE20080225123112002008022512322100{FDD26BCC-BCE0-450E-9A08-5BC427493B10}Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780enContinuous 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.To provide processed resistivity data as a point shapefile.John F. Bratton2008Processed Continuous Resistivity Point Data from Cape Cod National Seashore, Feb. 28, 2006mrg2006_allxyzvector digital datahttp://pubs.usgs.gov/of/2006/1169/data/gis/resistivity/mrg2006_allxyz.zipSubmarine Hydrogeological Data from Cape Cod National SeashoreVeeAnn A. CrossJohn F. BrattonJohn CrusiusJohn A. ColmanTimothy D. McCobb2008Open-File Report2006-1169Woods Hole Science Center, Woods Hole, MAU.S. Geological Survey, Coastal and Marine Geology Programhttp://pubs.usgs.gov/of/2006/1169/Open-File Report2006-1169Woods Hole Science Center, Woods Hole, MAU.S. Geological Survey, Coastal and Marine Geology Programhttp://pubs.usgs.gov/of/2006/1169/htmldocs/catalog.htmground condition20060228None planned-69.973172-69.94535041.83693341.820967-69.973172-69.94535041.82096741.836838GeneralAtlantic OceanCape CodMassachusettsNorth AmericaUnited StatesSalt PondNauset MarshCape Cod National SeashoreGeneralCMGPCoastal and Marine Geology ProgramContinuous Resistivity ProfilingCRPground-waternavigationOF 2006-1169Open-File Reportpointshapefilesubmarine ground-waterU.S. Geological SurveyUSGSWoods Hole Science CenterWHSC field activity serial number 06007environmentgeoscientificInformationinlandWaterslocationISO 19115 Topic CategoryoceansNone.The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.ShapefileJohn F. BrattonU.S. Geological Surveymailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598508-548-8700 x2254508-457-2210jbratton@usgs.govMicrosoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780mrg2006_allxyz-69.973172-69.9453541.83683841.8209671-69.973172-69.9453541.83683841.8209671enFGDC Content Standards for Digital Geospatial MetadataFGDC-STD-001-1998local timeVeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.gov20080225http://www.esri.com/metadata/esriprof80.htmlESRI Metadata ProfileISO 19115 Geographic Information - MetadataDIS_ESRI1.0datasetDownloadable DataNeither 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.5.5405.540SHPWinZipNone.John F. BrattonU.S. Geological Surveymailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2254(508) 457-2310jbratton@usgs.govThese data are available in Environmental Systems Research Institute (ESRI) shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from ESRI at www.esri.com.002file://\\VEECRODTXP\E$\pubs_in_progress\cc_resofr\data\gis\resistivity\mrg2006_allxyz.shpLocal Area Network5.540Shapefile20080225The data were transferred from the logging computer via AGISSAdmin software. The data files available for this day are l1*, l2*, l3*, l4*, l5*, l6*, l8*, l9*, l10*, l11*, l12*, l13*, l14*, and l15*. ***Of note, on lines 1 and 2, during acquisition the distance between the cable connection point and the first electrode was entered as 10 meters instead of -10 meters. This can be adjusted when reading the data into Marine Log Manager for linearization.2006Emile M. BergeronU.S. Geological SurveyElectronics Technicianmailing address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2337(508) 457-2313ebergeron@usgs.gov$GPRMC lines with the GPS file that had bad time stamps or were otherwise corrupt were deleted.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThe 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.AGISSAdmin version 1.33.182; MLM version 1.03.92006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThese 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.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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThe 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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govWith 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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThe DEP file was checked for anomalous bathymetry values, or duplicated distance along values, and those lines in the file were deleted.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govEarthImager 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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govEarthImager 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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThe 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.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govTo be consistent with the 2004 data, an ArcView 3.3 avenue script (createatdistance.ave) was used to read the XYZ output file and based on the distance along value, extract the geographic X and Y position based on the polyline trackline. The result is a point shapefile for each line of information in the XYZ file.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govEach individual XYZ shapefile was merged into a single point shapefile.2006VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govOnly those lines with valid resistivity data are represented here.No additional checks for topological consistency other than visual inspection were performed on the data.VectorSimplePointFALSE207466FALSEFALSEEntity point207466GCS_North_American_1983Decimal degrees0.0000000.000000North American Datum of 1983Geodetic Reference System 806378137.000000298.257222GCS_North_American_1983207466mrg2006_allxyzFeature Class207466FIDFIDOID400Internal feature number.ESRISequential unique whole numbers that are automatically generated.ShapeShapeGeometry000Feature geometry.ESRICoordinates defining the features.IDIDNumber8Software generated identification number.Software.131092DISTDISTNumber124Distance along line (in meters) that the point occurs. A negative value indicates the beginning of the line was extended to recoup the beginning portion of the line before the streamer passed the initial GPS position.Processing software calculated.-34.72643.0metersLONGITUDELONGITUDENumber126Longitude position of the data point.Software calculated.-69.973172-69.945350decimal degreesLATITUDELATITUDENumber126Latitude position of the data point.Software calculated.41.82096741.836838decimal degreesUTMXUTMXNumber101UTM easting, based on UTM Zone 19 NAD83, position of the data point.Software calculated.419195.9421498.3metersUTMYUTMYNumber101UTM northing, based on UTM Zone 19 NAD83, position of the data point.Software calculated.4630342.84632116.6metersDEPTHDEPTHNumber124Depth from water surface (in meters) where the data point occurs. (Negative value indicates below the water surface.)Processing software generated.-14.19950metersRESVALUERESVALUENumber126Resistivity value of the data point.Processing software calculated.0.1541.465ohm-metersLINELINEString16Resistivity trackline which the data point is from.Data processor.character set