Metadata: Identification_Information: Citation: Citation_Information: Originator: Peter Dartnell Originator: Rikk G. Kvitek Publication_Date: 2014 Title: BackscatterB [Swath]--Offshore of Salt Point Map Area, California Edition: 1.0 Geospatial_Data_Presentation_Form: GeoTiff Larger_Work_Citation: Citation_Information: Originator: Samuel Y. Johnson Originator: Peter Dartnell Originator: Nadine E. Golden Originator: Stephen R. Hartwell Originator: H. Gary Greene Originator: Mercedes D. Erdey Originator: Guy R. Cochrane Originator: Rikk G. Kvitek Originator: Michael W. Manson Originator: Charles A. Endris Originator: Bryan E. Dieter Originator: Janet T. Watt Originator: Lisa M. Krigsman Originator: Ray W. Sliter Originator: Erik N. Lowe Originator: John L. Chin Publication_Date: 2015 Title: California State Waters Map Series--Offshore of Salt Point map area, California Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: Open-File Report Issue_Identification: OFR 2015-1098 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/2015/1098/ Larger_Work_Citation: Citation_Information: Originator: Nadine E. Golden Publication_Date: 2013 Title: California State Waters Map Series Data Catalog Geospatial_Data_Presentation_Form: database Series_Information: Series_Name: Data Series Issue_Identification: DS 781 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/ds/781/ Description: Abstract: This part of DS 781 presents data for the acoustic-backscatter map of the Offshore of Salt Point map area, California. Backscatter data are provided as separate grids depending on mapping system or processing method. The raster data files are included in "BackscatterB_Swath_OffshoreSaltPoint.zip", which are accessible from http://pubs.usgs.gov/ds/781/OffshoreSaltPoint/data_catalog_OffshoreSaltPoint.html. The acoustic-backscatter map of the Offshore of Salt Point map area, California, was generated from backscatter data collected by California State University, Monterey Bay (CSUMB), and by Fugro Pelagos. Mapping was completed between 2007 and 2010, using a combination of 200-kHz and 400-kHz Reson 7125, and 244-kHz Reson 8101 multibeam echosounders, as well as 468-kHz SEA SWATHPlus interferometric system. These mapping missions combined to collect backscatter data from about the 10-m isobath to beyond the 3-nautical-mile limit of California State Waters. Within the acoustic-backscatter imagery, brighter tones indicate higher backscatter intensity, and darker tones indicate lower backscatter intensity. The intensity represents a complex interaction between the acoustic pulse and the seafloor, as well as characteristics within the shallow subsurface, providing a general indication of seafloor texture and composition. Backscatter intensity depends on the acoustic source level; the frequency used to image the seafloor; the grazing angle; the composition and character of the seafloor, including grain size, water content, bulk density, and seafloor roughness; and some biological cover. Harder and rougher bottom types such as rocky outcrops or coarse sediment typically return stronger intensities (high backscatter, lighter tones), whereas softer bottom types such as fine sediment return weaker intensities (low backscatter, darker tones). These data are not intended for navigational purposes. Purpose: To expand geologic mapping to the seafloor within the California's State Waters, to update coastal geologic mapping, and to contribute to a uniform regional geologic database, which can be used geographic information systems. Additionally, to provide a geologic map for the public and geoscience community to aid in assessments and mitigation of geologic hazards in the Point Reyes coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. This information is not intended for navigational purposes. Supplemental_Information: None Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2007 Ending_Date: 2010 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -123.48 East_Bounding_Coordinate: -123.28 North_Bounding_Coordinate: 38.64 South_Bounding_Coordinate: 38.48 Keywords: Theme: Theme_Keyword_Thesaurus: Global Change Master Directory (GCMD) Theme_Keyword: Oceans > Bathymetry/SeafloorTopography > Bathymetry Theme_Keyword: Oceans > Bathymetry/SeafloorTopography > Seafloor Topography Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: environment Theme_Keyword: oceans Theme_Keyword: imageryBaseMapsEarthCover Theme: Theme_Keyword_Thesaurus: General Theme_Keyword: Seafloor Character Theme_Keyword: Fisheries Theme_Keyword: Ecosystem Theme_Keyword: Multibeam Theme_Keyword: Geology Theme_Keyword: Bathymetry Theme_Keyword: Backscatter Theme_Keyword: Intensity Theme_Keyword: Ocean Floor Topography Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: CMGP Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Pacific Ocean Place_Keyword: State of California Place_Keyword: Northern California Place_Keyword: Salt Point Place_Keyword: Sonoma County Access_Constraints: If physical samples or materials are available, constraints on their on-site access are described in "WR CMG Sample Distribution Policy" at URL: http://walrus.wr.usgs.gov/infobank/programs/html/main/sample-dist-policy.html Use_Constraints: This information is not intended for navigational purposes. This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. USGS-authored or produced data and information are in the public domain. Acknowledge the U.S. Geological Survey and California State University, Monterey Bay, Seafloor Mapping Lab in products derived from these data. Share data products developed using these data with the U.S. Geological Survey. This information is not intended for navigational purposes. Read and fully comprehend the metadata prior to data use. Uses of these data should not violate the spatial resolution of the data. Where these data are used in combination with other data of different resolution, the resolution of the combined output will be limited by the lowest resolution of all the data. Although this Federal Geographic Data Committee-compliant metadata file is intended to document these data in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Peter Dartnell Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: 400 Natural Bridges Dr. City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7415 Contact_Facsimile_Telephone: (831) 427-4709 Contact_Electronic_Mail_Address: pdartnell@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: Browse_Graphic_File_Description: Acoustic backscatter imagery of the Offshore of Salt Point map area. Browse_Graphic_File_Type: JPEG Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Not applicable for raster data. Logical_Consistency_Report: Unspecified Completeness_Report: Complete Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Horizontal_Positional_Accuracy_Report: Estimated to be no less than 2 m, owing to water depth and total propagated uncertainties of the mapping systems, which include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning, gridding, and datum transformations. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Not Applicable Lineage: Process_Step: Process_Description: During the Fugro Pelagos and CSUMB mapping missions, an Applanix Position and Motion Compensation System for Marine Vessels (POS/MV, 320, v4) was used to accurately position the vessels during data collection, and it also accounted for vessel's motion such as heave, pitch, and roll (position accuracy, +/-2 m; pitch, roll, and heading accuracy, +/-0.02; heave accuracy, +/-5%, or 5 cm). KGPS altitude data (Fugro Pelagos, StarFix HP & XP units; CSUMB, NavCom 2050) were used to account for tide cycle fluctuations and sound velocity profiles were collected with an Applied Microsystems SVPlus sound velocimeter. Soundings were corrected for vessel motion using the Applanix POS/MV data, for variations in water-column sound velocity using the AM SVPlus data, and for variations in water height (tides) using vertical-position data from the KGPS receivers. The multibeam backscatter data then were processed using Geocoder (Fugro Pelagos Modified Test Release 16) or Geocoder within Caris HIPS and SIPS. Within Geocoder, the backscatter intensities were radiometrically corrected (including despeckling and angle-varying gain adjustments), and the position of each acoustic sample was geometrically corrected for slant range. This processed imagery was stored as Georeferenced, Backscatter Rasters (GeoBARs). After GeoBARs were created for each line, they were mosaicked into 1-m or 2-m resolution images. Overlap between parallel lines was resolved using a priority table based on the distance of each sample from the ship track, with samples closest to- and furthest from- the ship track given the lowest priority. An anti-aliasing algorithm was also applied. The SWATHPlus backscatter data were processed using SXPTools v 2.0 (David Finlayson, USGS) and SEA Grid Processor v 3.02.19.0. SXPTools is a collection of command line programs that are used to enhance the quality of SEA SWATHplus interferometric sidescan sonar data. The programs are primarily focused on enhancing the backscatter quality, but there is some benefit to the bathymetry as well. The SXPTools sxpegn command was used to equalize the backscatter amplitude, and the sxpmagic command was used to help fill gaps and remove artifacts near nadir. After processing with SXPTools, lines were imported into Grid Processor and mosaicked into 1-m or 2-m resolution image georeferenced to UTM Zone 10 N, NAD_83(CORS96). The mosaic image for each survey block was exported as a GeoJpeg from Grid Processor and converted to GeoTiff using Adobe Photoshop or GIMP. In some cases memory limitations in Grid Processor required tiling a block mosaic into 2 or more sub-mosaics. Process_Date: 2010 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Carrie Bretz Contact_Organization: Seafloor Mapping Lab, California State University Monterey Bay Contact_Position: Projects Manager, GIS; Metadata Supervisor Contact_Address: Address_Type: mailing and physical address Address: 100 Campus Center, Bldg 13 City: Seaside State_or_Province: CA Postal_Code: 93955 Country: USA Contact_Voice_Telephone: (831) 582-4197 Contact_Electronic_Mail_Address: carrie_bretz@csumb.edu Process_Step: Process_Description: California Seafloor Mapping Project 1- or 2-m resolution backscatter imagery within this map were downloaded from California State University, Monterey Bay, Seafloor Mapping Lab (http://seafloor.csumb.edu/SFMLwebDATA.htm) and converted to grids. Backscatter grids of similar mapping systems were merged in a GIS and clipped to the boundary of the map area. Grids from different mapping systems were not merged together due to different mapping frequencies and processing techniques. Grids were projected horizontally to WGS-84 using ESRI ArcTools. Process_Date: 2013 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Pete Dartnell Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: 400 Natural Bridges Dr. City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7415 Contact_Electronic_Mail_Address: pdartnell@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 8910 Column_Count: 8930 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: 10 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -123.00000 Latitude_of_Projection_Origin: 0.00000 False_Easting: 500000.0 False_Northing: 0.00 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 2.0 Ordinate_Resolution: 2.0 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: WGS84 Ellipsoid_Name: WGS84 Semi-major_Axis: 6378137.00 meters Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: The merged Reson 8101 acoustic-backscatter grid was originally archived as an ESRI grid with the following attributes: >Cell size = 2.0 >Number of rows = 8900 >Number of columns = 8885 > >Data type = unsigned integer > >Boundary >Xmin = 473300 >Xmax = 491070 >Ymin = 4249780 >Ymax = 4267580 > >Statistics >Minimum value = 0 >Maximum value = 254 >Mean = 124.90 >Standard deviation = 24.62 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter The merged Reson 7125 acoustic-backscatter grid was originally archived as an ESRI grid with the following attributes: >Cell size = 2.0 >Number of rows = 8900 >Number of columns = 8885 > >Data type = unsigned integer > >Boundary >Xmin = 473300 >Xmax = 491070 >Ymin = 4249780 >Ymax = 4267580 > >Statistics >Minimum value = 0 >Maximum value = 254 >Mean = 96.41 >Standard deviation = 27.76 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter The merged SWATHPlus acoustic-backscatter grid was originally archived as an ESRI grid with the following attributes: >Cell size = 2.0 >Number of rows = 8900 >Number of columns = 8885 > >Data type = unsigned integer > >Boundary >Xmin = 473300 >Xmax = 491070 >Ymin = 4249780 >Ymax = 4267580 > >Statistics >Minimum value = 1 >Maximum value = 254 >Mean = 112.70 >Standard deviation = 41.48 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter Entity_and_Attribute_Detail_Citation: none Detailed_Description: Entity_Type: Entity_Type_Label: Value Entity_Type_Definition: BackscatterB [Swath] intensity value Entity_Type_Definition_Source: ESRI Attribute: Attribute_Label: Rowid 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: Backscatter intensity values Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 254 Attribute_Units_of_Measure: Integers representing intensity values Attribute: Attribute_Label: COUNT Attribute_Definition: The number of pixels (2m x 2m size grid cell) represented in each intensity value (see Attribute: VALUE). Attribute_Definition_Source: ESRI Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 12936 Attribute_Units_of_Measure: Integers Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical address Address: 345 Middlefield Rd City: Menlo Park State_or_Province: CA Postal_Code: 94025-3561 Country: USA Contact_Voice_Telephone: (650) 329-4309 Distribution_Liability: These databases, identified as acoustic-backscatter maps of Offshore Salt Point map area, California have been approved for release and publication by the U.S. Geological Survey (USGS). Although these databases have been subjected to rigorous review and are substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. These data are not intended for navigational use. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: TIFF Format_Version_Number: ArcMap (version 10.0, ESRI , 2011) Format_Specification: Raster data layer is registered TIFF image in the UTM Zone 10 coordinate system with datum WGS84. Format_Information_Content: The .zip file for the TIFF image includes the image (.tif), the world registration file (.tfw), and the text (.txt) and XML (.tif.xml) versions of the metadata for the BackscatterB [Swath] data layer of Offshore Salt Point, California. File_Decompression_Technique: WinZip Transfer_Size: 15.5 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/ds/781/OffshoreSaltPoint/data/BackscatterB_Swath_OffshoreSaltPoint.zip Network_Resource_Name: http://pubs.usgs.gov/ds/781/ Access_Instructions: Data can be downloaded via the World Wide Web (WWW) Fees: none Technical_Prerequisites: The downloadable data file has been compressed with the "zip" command and can be unzipped with Winzip (or other tool) on Windows systems. To utilize these data, the user must have software capable of uncompressing the WinZip file and importing and viewing an Esri ArcMap TIFF. Users should download the ArcGIS Project File, OffshoreSaltPointGIS.mxd.zip, a compressed (with the "zip" command) version of the ArcMap document (.mxd) that has all the data layers loaded in the table of contents for "Offshore Salt Point" and has all the data symbolized as on the data release map sheets. Download and save this ArcGIS project file, including all data layers, to the directory the user has created for this GIS. Metadata_Reference_Information: Metadata_Date: 20140630 Metadata_Review_Date: 20150513 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Peter Dartnell Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: 400 Natural Bridges Dr. City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7415 Contact_Facsimile_Telephone: (831) 427-4709 Contact_Electronic_Mail_Address: pdartnell@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata ("CSDGM version 2") Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: universal time