Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2007 Title: TRANSGR_GRD - ESRI ArcRaster grid representing the elevation of the regional transgressive unconformity underlying the inner shelf of Long Bay, South Carolina Edition: 1.0 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: Open-File Issue_Identification: 2005-1346 Online_Linkage: http://pubs.usgs.gov/of/2005/1346/arcgis/sf_env/seafloorenv.zip Larger_Work_Citation: Citation_Information: Originator: Baldwin, W.E. Originator: Denny, J.F. Originator: Schwab, W.C. Originator: Gayes, P.T. Originator: Morton, R.A. Originator: Driscoll, N.W. Publication_Date: 2007 Title: Geologic Framework Studies of South Carolina's Long Bay from Little River Inlet to Winyah Bay, 1999-2003; geospatial data release Edition: 1.0 Series_Information: Series_Name: Open-File Report Issue_Identification: 2005-1346 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/2005/1346/ Description: Abstract: In 1999, the USGS, in partnership with the South Carolina Sea Grant Consortium, began a study to investigate processes affecting shoreline change along the northern coast of South Carolina, focusing on the Grand Strand region. Previous work along the U.S. Atlantic coast shows that the structure and composition of older geologic strata located seaward of the coast heavily influences the coastal behavior of areas with limited sediment supply, such as the Grand Strand. By defining this geologic framework and identifying the transport pathways and sinks of sediment, geoscientists are developing conceptual models of the present-day physical processes shaping the South Carolina coast. The primary objectives of this research effort are: 1) to provide a regional synthesis of the shallow geologic framework underlying the coastal upland, shoreface and inner continental shelf, and define its role in coastal evolution and modern beach behavior; 2) to identify and model the physical processes affecting coastal ocean circulation and sediment transport, and to define their role in shaping the modern shoreline; and 3) to identify sediment sources and transport pathways; leading to construction of a regional sediment budget. Purpose: This data set contains a surface depicting the elevation of the regional transgressive unconformity underlying the inner shelf of Long Bay, offshore of the South Carolina Grand Strand. Chirp seismic data collected with Benthos SIS-1000 and Edgetech SB-512 acquisition systems were processed using SIOSEIS (Scripps Institute of Oceanography) and Seismic Unix (Colorado School of Mines) to produce segy files and jpg images of the profiles. Data were then imported into Landmark SeisWorks, a digital seismic interpretation package, where the sea floor and underlying transgressive surface were interpreted and digitized. The isopach between these horizons was exported at every 50th shot as xyz points, and imported to ArcGIS for interpolation into a 10-m raster grid. The isopach grid was then subtracted from a seafloor bathymetry grid (bathy_grd) to approximate the proper elevation of the transgressive unconformity beneath the sea floor. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1999 Ending_Date: 2003 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -79.158619 East_Bounding_Coordinate: -78.514899 North_Bounding_Coordinate: 33.855993 South_Bounding_Coordinate: 33.188888 Keywords: Theme: Theme_Keyword_Thesaurus: General Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Woods Hole Science Center Theme_Keyword: WHSC Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: seismic reflection profiles Theme_Keyword: seafloor geology Theme_Keyword: Benthos SIS-1000 Theme_Keyword: Edgetech SB-512 Theme_Keyword: Chirp Theme_Keyword: ArcGIS Raster Theme_Keyword: transgressive unconformity Theme_Keyword: elevation Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: oceans and coastal Theme_Keyword: oceans and estuaries Theme_Keyword: geoscientificInformation Place: Place_Keyword_Thesaurus: General Place_Keyword: South Carolina Place_Keyword: Grand Strand Place_Keyword: North Myrtle Beach Place_Keyword: Myrtle Beach Place_Keyword: Surfside Place_Keyword: Garden City Place_Keyword: Pawleys Island Place_Keyword: Waites Island Place_Keyword: Southeast United States Place_Keyword: United States Place_Keyword: Atlantic Ocean Access_Constraints: None Use_Constraints: Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Wayne Baldwin Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2226 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: wbaldwin@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2005/1346/images/transgr_grd.jpg Browse_Graphic_File_Description: elevation of regional transgressive unconformity underlying the Long Bay inner shelf Browse_Graphic_File_Type: JPEG Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: These data were interpretted from seismic-reflection and bathymetric data at a regional scale of 1:75,000. Completeness_Report: All interpretations of paleochannel unconformities are present in this data set Logical_Consistency_Report: No additional checks for topological consistency were performed on the data. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Interpretations are derived from seismic-reflection and bathymetric data at a regional scale of 1:75000. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Seismic data are not corrected for tides. Thickness of Holocene surficial sediments was calculated as the distance between the seafloor and the underlying transgressive surface from interpretation of seismic reflection profiles. An isopach grid of the thickness of Holocene surficial sediments (sedthick_grd) was then subtracted from a gridded surface of seafloor bathymetry (bathy_grd) to generate a grid representing the regional elevation beneath the seafloor. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2007 Title: SEDTHICK_GRD - ESRI ArcRaster representing the isopach of Holocene surficial sediment within the inner shelf of Long Bay, South Carolina Edition: 1.0 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: Open-File Issue_Identification: 225-1346 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/2005/1346/arcgis/seismic_srf/sedthick_grd.zip Larger_Work_Citation: Citation_Information: Originator: Baldwin, W.E. Originator: Denny, J.F. Originator: Schwab, W.C. Originator: Gayes, P.T. Originator: Morton, R.A. Originator: Driscoll, N.W. Publication_Date: 2007 Title: Geologic Framework Studies of South Carolina's Long Bay from Little River Inlet to Winyah Bay, 1999-2003; geospatial data release Edition: 1.0 Series_Information: Series_Name: Open-File Report Issue_Identification: 2005-1346 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/2005/1346/ Type_of_Source_Media: DVD-ROM Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2007 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: sedthick_grd, v1.0, 2006 Source_Contribution: This data set contains polygons that identify the geologic unit type present in outcrop or subcrop along the Long Bay inner shelf. Polygon areas are based upon digital interpretations of Chirp seismic reflection data and coastal plain boreholes. A polygon outlining the inner shelf study area was erased (ArcGIS Analysis toolbox) in iterations using polygons outlining gridded surfaces of Holocene surficial sediment (sedthick_grd) and paleochannel unconformities (paleoch_grd). Outside of the area covered by the Holocene surficial sediment grid, seismic data indicate surficial sediment cover of < 50 cm. In these areas, paleochannel fills, Cretaceous, and Tertiary units are interpreted to crop out at the sea floor, or subcrop near the surface. Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2007 Title: BATHY - Bathymetry within the inner shelf of Long Bay, South Carolina collected by the USGS, 1999-2003 (Grid) Edition: 1.0 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: Open-File Issue_Identification: 2005-1346 Publication_Information: Publication_Place: Woods Hole Science Center, Woods Hole, MA Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/2005/1346/arcgis/bathy/bathy_grd.zip Larger_Work_Citation: Citation_Information: Originator: Baldwin, W.E. Originator: Denny, J.F. Originator: Schwab, W.C. Originator: Gayes, P.T. Originator: Morton, R.A. Originator: Driscoll, N.W. Publication_Date: 2007 Title: Geologic Framework Studies of South Carolina's Long Bay from Little River Inlet to Winyah Bay, 1999-2003; geospatial data release Edition: 1.0 Series_Information: Series_Name: Open-File Report Issue_Identification: 2005-1346 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/2005/1346/ Type_of_Source_Media: DVD-ROM Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2007 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: bathy, v1.0, 2006 Source_Contribution: This data set contains polygons that identify the geologic unit type present in outcrop or subcrop along the Long Bay inner shelf. Polygon areas are based upon digital interpretations of Chirp seismic reflection data and coastal plain boreholes. A polygon outlining the inner shelf study area was erased (ArcGIS Analysis toolbox) in iterations using polygons outlining gridded surfaces of Holocene surficial sediment (sedthick_grd) and paleochannel unconformities (paleoch_grd). Outside of the area covered by the Holocene surficial sediment grid, seismic data indicate surficial sediment cover of < 50 cm. In these areas, paleochannel fills, Cretaceous, and Tertiary units are interpreted to crop out at the sea floor, or subcrop near the surface. Process_Step: Process_Description: The ARCGIS raster calculator was used to subract a grid representing Holocene surficial sediments (sedthick_grd) from the regional seafloor bathymetry grid (bathy_grd) to approximate the proper elevation of the transgressive unconformity beneath the sea floor. Source_Used_Citation_Abbreviation: sedthick_grd, v1.0, 2006 Source_Used_Citation_Abbreviation: bathy, v1.0, 2006 Process_Date: 2003 Source_Produced_Citation_Abbreviation: trans_grd Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Wayne Baldwin Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Country: USA Contact_Voice_Telephone: 508-548-8700 x2226 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: wbaldwin@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 728 Column_Count: 583 Vertical_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 17 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -81.00000 Latitude_of_Projection_Origin: 0.0000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 100.000 Ordinate_Resolution: 100.000 Planar_Distance_Units: meters 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: Mean lower low water Depth_Resolution: 0.5 Depth_Distance_Units: meters Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Elevation of paleochannel unconformities in ESRI GRID format. Entity_and_Attribute_Detail_Citation: usgs Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Wayne Baldwin Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Country: USA Contact_Voice_Telephone: 508-548-8700 x2226 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: wbaldwin@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: Although all data have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and/or related materials. 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: ARCG Format_Version_Number: ArcGIS 9.0 Format_Specification: ESRI ArcRaster GRID format Format_Information_Content: no compression applied Transfer_Size: 2.266 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2005/1346/arcgis/seismic_srf/transgr_grd.zip Access_Instructions: Data can be downloaded via the World Wide Web (WWW) Offline_Option: Offline_Media: DVD-ROM Recording_Capacity: Recording_Density: 4.75 Recording_Density_Units: Gbytes Recording_Format: UDF Fees: None Technical_Prerequisites: These data are available in Environmental Systems Research Institute (ESRI) GRID format. The user must have software capable of importing and processing the data file. Metadata_Reference_Information: Metadata_Date: 20070123 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Wayne Baldwin Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2226 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: jdenny@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