Identification_Information: Citation: Citation_Information: Originator: VeeAnn A. Cross Publication_Date: 2010 Title: MRG2006_ALLZYZ.SHP: Processed Continuous Resistivity Profile (CRP) Data Below the Sediment Water Interface From the Potomac River/Chesapeake Bay collected from Sept. 6, 2006 to Sept. 8, 2006 on USGS Cruise 06018 Geospatial_Data_Presentation_Form: vector digital data Series_Information: Series_Name: Open-File Report Issue_Identification: 2009-1151 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/2009/1151/data/resistivity/shapefiles/mrg2006_allxyz.zip Online_Linkage: http://pubs.usgs.gov/of/2009/1151/html/catalog.html Larger_Work_Citation: Citation_Information: Originator: VeeAnn A. Cross Originator: David S. Foster Originator: John F. Bratton Publication_Date: 2010 Title: Continuous Resistivity Profiling and Seismic-Reflection Data Collected in 2006 from the Potomac River Estuary, Virginia and Maryland Series_Information: Series_Name: Open-File Report Issue_Identification: 2009-1151 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/2009/1151/ Description: Abstract: In order to test hypotheses about groundwater flow under and into Chesapeake Bay, geophysical surveys were conducted by U.S. Geological Survey (USGS) scientists on Chesapeake Bay and the Potomac River Estuary in September 2006. Chesapeake Bay resource managers are concerned about nutrients that are entering the estuary via submarine groundwater discharge, which are contributing to eutrophication. The USGS has performed many related studies in recent years to provide managers with information necessary to make informed decisions about this issue. The research carried out as part of the study described here was designed to help refine nutrient budgets for Chesapeake Bay by characterizing submarine groundwater flow and discharge of groundwater beneath part of the mainstem and a major tributary, the Potomac River Estuary. Purpose: The purpose of these data are to release all the processed continuous resistivity profile data that occurs at the sediment water interface or below in a shapefile format collected on USGS cruise 06018. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20060906 Ending_Date: 20060908 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -76.856023 East_Bounding_Coordinate: -76.310406 North_Bounding_Coordinate: 38.295740 South_Bounding_Coordinate: 37.946757 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 Serial Number 06018 Theme_Keyword: Info Bank ID K-1-06-CH Theme_Keyword: navigation Theme_Keyword: bathymetry Theme_Keyword: Continuous Resistivity Profiling Theme_Keyword: CRP Theme_Keyword: R/V Kerhin Theme_Keyword: Lowrance GPS Theme_Keyword: AGI SuperSting Theme_Keyword: processed data Theme_Keyword: groundwater Theme_Keyword: submarine groundwater Theme_Keyword: point shapefile Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: elevation Theme_Keyword: inlandWaters 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 Place_Keyword: United States Place_Keyword: Virginia Place_Keyword: Potomac River Estuary Place_Keyword: Chesapeake Bay Place_Keyword: Dennis Point Marina Place_Keyword: Solomons, Maryland Place_Keyword: Maryland Place_Keyword: Patuxent River 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 Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2009/1151/data/resistivity/shapefiles/mrg2006_allxyz.gif Browse_Graphic_File_Description: Thumbnail image showing the location of the processed CRP data. The coastline is included for spatial reference. Browse_Graphic_File_Type: GIF Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 9.2.6.1500 Data_Quality_Information: Logical_Consistency_Report: All the data files were checked and handled in the same manner. Completeness_Report: All of the processed CRP data is incorporated into this shapefile. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The primary navigation system used was a Lowrance 480M with an LGC-2000 Global Positioning System (GPS) antenna. The antenna was located 7.9 meters forward of the anchor point for the resistivity streamer, and approximately 3 meters forward of the fathometer transducer. These offsets were not entered into the GPS system. Additionally, because of navigation and fathometers issues, periodically the ship's navigation system was used to supplement these data. The ship had a Differential GPS (DGPS) system with the antenna placed in the same location as the Lowrance antenna. The fathometer was located (hull-mounted) roughly directly below the antenna, so no horizontal offset. Because of the mixture of systems, the accuracy is on the order of 20 meters. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The source of the bathymetric values was dependant on the day of collection. On Sept. 6, 2006 (Julian day 249) all the bathymetric values were collected by the ship's fathometer. This fathometer was hull mounted approximately mid-ship, relatively close to the navigation antenna. The values are assumed to be accurate to within 1 meter. On Sept. 7, 2006 (Julian day 250) most of the bathymetric values were collected by the Lowrance fathometer. This fathometer was mounted mid-ship on the starboard side of the boat. The Lowrance manufacturer indicates the speed of sound used by the system to convert to depths is 4800 feet/second. On Sept. 8, 2006 (Julian day 251) the bathymetric values were collected by the Lowrance fathometer. 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 100-m streamer with an 11 electrode array with electrodes spaced 10 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. 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 transducer also contains a temperature sensor which was not working on Julian Day 249. Lowrance indicates the speed of sound used by the system is 4800 feet/second. On the first day of data collection (Julian Day 249, Sept. 6, 2006) the Lowrance transducer was side-mounted mid-ship on the port side of the boat. The remainder of the cruise the transducer was side-mounted mid-ship of the starboard side of the boat. 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: One of the resulting files from processing resistivity data with AGI's EarthImager software is an XYZ file. This XYZ file has three columns of information: distance along line (meters), resistivity reading depth (meters), resistivity value (ohm-m). One of the resulting files from linearization of the raw STG resistivity data is a DEP file. The DEP file has four columns of information: distance along line (meters), water depth (meters), latitude, longitude. This DEP file is dependant on the presence of bathymetry data in the originally recorded GPS file, or the addition of bathymetry information to that GPS file. This DEP file is used in the EarthImager processing and is carried over to the processing output. The Matlab script justbelowsed.m combines these two data files such that the output is only the resistivity values that fall at or below the sediment water interface. This script was written by the USGS in Woods Hole. In order to have a value at the sediment water interface, the software usually has to interpolate values. The version of Matlab used for these data was Matlab 7.5.0.342 (R2007b). An example of the script usage in Matlab is: justbelowsed('F10L1_lin_AllInvRes.xyz','F10L1_lin_wres.dep'). The output is: F10L1_lin_AllInvRes_jbsed.xyz. This resulting XYZ file has 5 columns of information: distance along line (meters); depth below water surface (meters); depth below sediment/water interface (meters); resistivity value (ohm-m); log(10) resistivity value. This process step and all subsequent process steps were performed by the same person - VeeAnn A. Cross. Source_Used_Citation_Abbreviation: *.dep Source_Used_Citation_Abbreviation: *.xyz Process_Date: 2009 Source_Produced_Citation_Abbreviation: *_jbsed.xyz 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: Using ArcMap 9.2 and VACExtras v 2.05 (extension developed by the USGS in Woods Hole) these XYZ files are converted to shapefiles. The tool in VACExtras to do this is "convert resistivity to shapefile". This tool requires the data frame be in a UTM projection, the active layer in the data frame needs to be a polyline shapefile with one record selected (the polyline navigation file) and the user is prompted for the file from justbelowsed.m. The program uses the distance along value to find an actual latitude and longitude. The software assumes the datum of the data layer and the data frame projection are the same. The conversion of the Easting and Northing locations to latitudes and longitudes is done by the tool. The result is a point shapefile with 11 columns of information. The Id attribute is automatically generated upon creation of a shapefile, the LINENAME attribue is the line name as indicated within the polyline shapefile that the program prompts the user for, dist is the distance along attribute carried over from the Matlab file, the attributes of location information (latitude, longitude, utmx, utmy) are calculated by the tool, the attributes depth, dep_b_sed, resvalue, and reslogval are carried over from the Matlab file. The Entity and Attribute section further describes these attribues and their units. Source_Used_Citation_Abbreviation: resgpslns_jd249.shp Source_Used_Citation_Abbreviation: resgpslns_jd250.shp Source_Used_Citation_Abbreviation: resgpslns_jd251.shp Source_Used_Citation_Abbreviation: all the *jbsed.xyz files Process_Date: 2009 Source_Produced_Citation_Abbreviation: all the point shapefiles for each individual line Process_Step: Process_Description: With all the individual point shapefiles in ArcMap 9.2, ArcToolbox - Data management Tools - General - Merge was used to combine the individual files into a single shapefile. The input was all the individual point shapefiles, with the output being mrg2006_allxyz.shp. Source_Used_Citation_Abbreviation: all the individual point shapefiles. Process_Date: 2009 Source_Produced_Citation_Abbreviation: mrg2006_allxyz.shp Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 1110279 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: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: mrg2006_allxyz Entity_Type_Definition: ESRI point shapefile Entity_Type_Definition_Source: ESRI Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: ESRI Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: Id Attribute_Definition: An automatically generated numeric value. Attribute_Definition_Source: VACExtras v2.05 Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 0 Attribute: Attribute_Label: LINENAME Attribute_Definition: The alphanumeric name corresponding to the individual line of data collection that the point comes from. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Character set. Attribute: Attribute_Label: dist Attribute_Definition: Distance along line in meters. Originally calculated by the AGI processing software. Attribute_Definition_Source: Processing software calculated. Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 23424 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: longitude Attribute_Definition: Longitude position of the point (decimal degrees, NAD83) Attribute_Definition_Source: Processing software calculated (VACExtras - convert resistivity to shapefile). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -76.856023 Range_Domain_Maximum: -76.310406 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: latitude Attribute_Definition: Latitude position of the point (decimal degrees, NAD83) Attribute_Definition_Source: Processing software calculated (VACExtras - convert resistivity to shapefile). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 37.946757 Range_Domain_Maximum: 38.29574 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: utmx Attribute_Definition: Easting position of the point in meters (UTM, Zone 18, NAD83) Attribute_Definition_Source: Processing software calculated (VACExtras - convert resistivity to shapefile). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 337421.1 Range_Domain_Maximum: 385160.9 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: utmy Attribute_Definition: Northing position of the point in meters (UTM, Zone 18, NAD83) Attribute_Definition_Source: Processing software calculated (VACExtras - convert resistivity to shapefile). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 4200745.9 Range_Domain_Maximum: 4239516.2 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: depth Attribute_Definition: Depth (meters) of the resistivity value below the water surface. Attribute_Definition_Source: Acquisition software derived. Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -28.63 Range_Domain_Maximum: -1.5 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: dep_b_sed Attribute_Definition: Depth (meters) of the value below the sediment/water interface. Attribute_Definition_Source: Processing software derived (Matlab - justbelowsed.m). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -26.1 Range_Domain_Maximum: 0 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: resvalue Attribute_Definition: Resistivity value of the data point in ohm-m. Attribute_Definition_Source: Processing software calculated (AGI EarthImager). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.123268 Range_Domain_Maximum: 1000 Attribute_Units_of_Measure: ohm-m Attribute: Attribute_Label: reslogval Attribute_Definition: Log(10) of the resistivity value. Attribute_Definition_Source: Processing software calculated (Matlab justbelowsed.m). Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -0.909149 Range_Domain_Maximum: 3 Attribute_Units_of_Measure: Log(10) of ohm-m 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: 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 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: WinZip Format_Version_Number: 9.0 Format_Information_Content: This WinZip file contains the point shapefile as well as the associated metadata files. Transfer_Size: 26.283 MB Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2009/1151/data/resistivity/shapefiles/mrg2006_allxyz.zip Network_Resource_Name: http://pubs.usgs.gov/of/2009/1151/html/catalog.html Offline_Option: Offline_Media: DVD-ROM Recording_Capacity: Recording_Density: 4.75 Recording_Density_Units: GBytes Recording_Format: UDF Fees: None. Technical_Prerequisites: This WinZip file contains data available in ESRI point shapefile format. The user must have software capable of uncompressing the WinZip file and reading/displaying the shapefile. Metadata_Reference_Information: Metadata_Date: 20100325 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