Identification_Information: Citation: Citation_Information: Originator: John F. Bratton Originator: VeeAnn A. Cross Publication_Date: 2014 Title: RES2DINV format continuous resistivity profiling data collected in the Indian River Bay, Delaware, on April 14, 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/res2dinv_format/apr14_res2dinv.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: The purpose of this dataset is to provide the linearized continuous resistivity profile data from the Indian River Bay, Delaware in the RES2DINV format. These data were collected by the AGI SuperSting system and recorded in the AGI format. RES2DINV is another format for resistivity data that is used by numerous universities and researchers. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20100414 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -75.194617 East_Bounding_Coordinate: -75.074800 North_Bounding_Coordinate: 38.615317 South_Bounding_Coordinate: 38.570800 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: continuous resistivity profiling Theme_Keyword: CRP Theme_Keyword: R/V Knob Theme_Keyword: AGI SuperSting Theme_Keyword: groundwater Theme_Keyword: submarine groundwater Theme_Keyword: RES2DINV format Theme_Keyword: Open-file Report 2011-1039 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: elevation 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: M.H. Loke Publication_Date: 2001 Title: Electrical imaging surveys for environmental and engineering studies - a practical guide to 2D and 3D surveys Publication_Information: Publication_Place: Penang, Malaysia Publisher: University Sains Malaysia Data_Quality_Information: Logical_Consistency_Report: All the data files were checked and handled in the same manner. Completeness_Report: All linearized resistivity data from this day were converted to the RES2DINV format. 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 move 1.6 m after making 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: The linearized STG and DEP files generated by AGI's Marine Log Manager software AGI SSAdmin MLM v 1.3.4 were converted to a format suitable for the RES2DINV processing software. The conversion was accomplished by a Visual Basic 6 program written at the USGS office in Woods Hole (AGI2res2d.exe - no version number). The lines processed on this day are L8F1, L9F1, L9F3, L10F1, L11F1, L11F2, L12F1, L13F1, L14F1, L15F1, L16F1, L17F1, L18F1, L19F1, L19F2, and L19F3. These line names are what the * refers to in the source used and source produced citations. A more complete description of all the processing involved prior to this point can be found in the metadata for the raw resistivity data and the processed resistivity data available at http://pubs.usgs.gov/of/2011/1039/html/ofr2011-1039-catalog.html. Source_Used_Citation_Abbreviation: *lin.stg Source_Used_Citation_Abbreviation: *wres.dep Process_Date: 201102 Source_Produced_Citation_Abbreviation: *res2d.dat 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 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Point 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 RES2DINV formatted CRP data from April 14, 2010 as well as the associated metadata files. Transfer_Size: 0.41 MB Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2011/1039/data/resistivity/res2dinv_format/apr14_res2dinv.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 data are provided in a zip compressed file. The user must have software capable of uncompressing the archive. In addition, these data are available in a format compatible with the RES2DINV resistivity inversion software. The user must have software capable of reading this format in order to process the data. 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