Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2007 Title: MOSAIC_COMP – Composite Sidescan-Sonar Mosaic collected by the U.S. Geological Survey offshore of the Grand Strand, SC (1999 – 2003) (Compressed - MrSID) Edition: 1.0 Geospatial_Data_Presentation_Form: remote-sensing image 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/arcgis/mosaic/mosaic_sid.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: Edition 1.0 Series_Information Series_Name 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 the sidescan-sonar imagery collected offshore of the Grand Strand, SC 1999 - 2003. These data are used in conjunction with surficial sediment analyses to define the sediment distribution within the survey area. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1999 Ending_Date: 2003 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -79.177122 East_Bounding_Coordinate: -78.492052 North_Bounding_Coordinate: 33.876672 South_Bounding_Coordinate: 33.143971 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: sidescan-sonar Theme_Keyword: sidescan Theme_Keyword: side scan sonar Theme_Keyword: backscatter Theme_Keyword: MrSID image Theme_Keyword: grey scale image Theme_Keyword: composite mosaic Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: oceans and coastal Theme_Keyword: oceans and estuaries Theme_Keyword: imageryBaseMapsEarthCover 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 as the originator of the dataset. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Jane Denny 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 x2311 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: jdenny@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2005/1346/images/mosaic.jpg Browse_Graphic_File_Description: grey-scale image of sidescan-sonar mosaic 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 measure the acoustic reflectivity of the seafloor. These values (Digital Number (DN)) are a relative measure of reflectivity within the study area and are internally consistent. Logical_Consistency_Report: These are raster data; all sidescan-sonar data collected during USGS field efforts offshore of Myrtle Beach, SC 1999 – 2003 are included. Processing removed any spurious data. Completeness_Report: No additional checks were made for topologic consistency. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: DGPS is assumed to be accurate within 1-2 meters. Standard GPS is assumed accurate within 5-10 meters. 99% of the positional data is DGPS. Unless noted, all GPS/DGPS data is referenced to WGS84 (NAD83). Slant-range distance is recorded between the sidescan-sonar tow vehicle and a sidemount rigged with an acoustic transponder. Offset between the sidemount and GPS antennae is measured. Basic trigonomic calculations use the slant-range offset to calculate a 'fish' (tow-vehicle) navigation. An assumption in these calculations is that the tow-vehicle is traveling directly behind the vessel; movement to port or starboard is not accounted for within 'fish' navigation. Thus, the horizontal accuracy of the sidescan-sonar tow-vehicle is 10 meters. Lineage: Process_Step: Process_Description: The sidescan-sonar data were acquired with a Benthos (Datasonics) SIS 1000 CHIRP sonar and Edgetech DF-1000 dual-frequency sonar systems. The SIS-100 operates in a frequency range of 100 - 120 kHz; the DF-1000 operates at 100 and 500 kHz. The sidescan-sonar imagery offshore of the Grand Strand is comprised of data acquired on six geophysical cruises operated by the USGS during 1999 - 2003. All sidescan-sonar data were logged digitally at a sample rate resulting in a 0.18-m pixel size in the across-track direction and approximately 0.14-m in the along-track direction following the methodology outlined in Danforth and others (1991). A median filtering routine (Malinverno and others, 1990) was applied to the sidescan-sonar data to remove speckle noise, resulting in a 0.73-m pixel size. The data for each survey were further processed and digitally mosaicked using PCI Geomatica Software and procedures described in Danforth and others (1991), Danforth (1997), and Paskevich (1992) resulting in an enhanced, geographically correct, sidescan-sonar mosaic with 2 meters/pixel resolution. The composite mosaic was exported as a TIFF image, with an associated ESRI world file. Source_Used_Citation_Abbreviation: Danforth, W.W., 1997, Xsonar/ShowImage: A complete system for rapid sidescan-sonar processing and display: U.S. Geological Survey Open File Report 97-686, 77 p. Source_Used_Citation_Abbreviation: Danforth, W.W., O'Brien, T.F., and Schwab, W.C., 1991, USGS Image processing system: near real-time mosaicking of high-resolution sidescan-sonar data Sea Technology, Vol 1, p.54-59. Source_Used_Citation_Abbreviation: Malinverno, A., Edwards, M, and Ryan, W.B.F, 1990, Processing of SeaMARC swath sonar data: IEEE, Journal of Ocean Engineering, v.15, p. 14-23. Source_Used_Citation_Abbreviation: Paskevich, V., 1992, Digital mapping of sidescan-sonar data with the Woods Hole Image Processing System software: U.S. Geological Survey Open-File Report 92-536, 87.p Process_Date: 1999 - 2003 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jane Denny 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 x2311 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: jdenny@usgs.gov Process_Step: Process_Description: The sidescan-sonar mosaic was compressed using MrSid. A compression of 20x was used. Process_Date: 2003 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jane Denny 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 x2311 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: jdenny@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Row_Count: 20000 Column_Count: 15500 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: -81.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 4.000000 Ordinate_Resolution: 4.000000 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 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Band_1 Entity_Type_Definition: Sidescan-Sonar image stored in MrSid format Entity_Type_Definition_Source: ESRI Attribute: Attribute_Label: ObjectID 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: Value Attribute_Definition: pixel values in the range of 0-255; 0 represents low backscatter; 255 represents high backscatter Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 255 Attribute_Units_of_Measure: digital number Attribute_Measurement_Resolution: 1 Attribute: Attribute_Label: Count Attribute_Definition: pixel count Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 249232064 Attribute_Units_of_Measure: unrepresented Attribute_Measurement_Resolution: 1 Overview_Description: Entity_and_Attribute_Overview: There are no attributes associated with a MrSid image. Image pixel values contain acoustic reflectivity values normalized to an 8-bit data range (0-255). Low-backscatter is represented by dark tones (low values) and high-backscatter is represented by bright tones (high values). Entity_and_Attribute_Detail_Citation: USGS Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey 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 Contact_Facsimile_Telephone: 508-457-2310 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: MrSID Format_Version_Number: ArcGIS 9.0 Format_Specification: MrSID Image compression Format_Information_Content: File contains the sidescan-sonar imagery collected offshore of the Grand Strand. SC File_Decompression_Technique: MrSID Image Compression Transfer_Size: 9.428 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2005/1346/arcgis/mosaic/mosaic_sid.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: This image is available as a compressed MrSID image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a MrSID image. Metadata_Reference_Information: Metadata_Date: 20070115 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Jane Denny 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 x2311 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_Access_Constraints: None Metadata_Use_Constraints: None