Metadata: Identification_Information: Citation: Citation_Information: Originator: Carrie K. Bretz Originator: Rikk G. Kvitek Originator: Peter Dartnell Originator: Mercedes D. Erdey Originator: Eleyne L. Phillips Publication_Date: 2014 Title: BackscatterA [8101]--Offshore Pacifica, California Edition: 1.0 Geospatial_Data_Presentation_Form: GeoTiff 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 Offshore of Pacifica map area, California. Backscatter data are provided as two separate grids depending on mapping system. The raster data files are included in "BackscatterA_8101_OffshorePacifica.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePacifica/data_catalog_OffshorePacifica.html. The acoustic-backscatter map of the Offshore of Pacifica, California was generated from backscatter data collected by Fugro Pelagos and by California State University, Monterey Bay (CSUMB). Mapping was completed between 2005 and 2007, using a combination of 400-kHz Reson 7125 and 244-kHz Reson 8101 multibeam echosounders. Within the final 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). Purpose: These data are intended for science researchers, students, policy makers, and the general public. These data can be used with geographic information systems or other software. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2005 Ending_Date: 2007 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -122.65 East_Bounding_Coordinate: -122.40 North_Bounding_Coordinate: 37.70 South_Bounding_Coordinate: 37.54 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:08a8b72c-4eb8-40e0-a313-3b9e95f0fc59 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: None 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 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: environment Theme_Keyword: oceans Theme_Keyword: imageryBaseMapsEarthCover Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: distributions Theme_Keyword: physical habitats and geomorphology Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: seabed Theme_Keyword: sidescan sonar Theme_Keyword: marine geophysics Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: sidescan sonar Theme_Keyword: image mosaics Theme_Keyword: marine geophysics Theme_Keyword: sea-floor characteristics Theme_Keyword: sea-floor acoustic reflectivity Theme: Theme_Keyword_Thesaurus: Coastal and Marine Ecological Classification Standard (CMECS) Theme_Keyword: Marine Nearshore Subtidal Theme_Keyword: Marine Offshore Subtidal Theme_Keyword: Transform Continental Margin Theme_Keyword: Continental/Island Shelf Theme_Keyword: Rock Substrate Theme_Keyword: Unconsolidated Mineral Substrate Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Pacific Ocean Place_Keyword: State of California Place_Keyword: Pacifica Place_Keyword: San Mateo County Place_Keyword: Rockaway Beach Place: Place_Keyword_Thesaurus: Coastal and Marine Ecological Classification Standard (CMECS) Place_Keyword: Northern California Ecoregion Stratum: Stratum_Keyword_Thesaurus: Coastal and Marine Ecological Classification Standard (CMECS) Stratum_Keyword: Substrate Access_Constraints: None Use_Constraints: 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. 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 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 offshore Pacifica. 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: 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 to acoustic-backscatter imagery. Lineage: Process_Step: Process_Description: During the mapping missions, an Applanix position and motion compensation system (POS/MV) was used to accurately position the vessel during data collection, and it also accounted for vessel motion such as heave, pitch, and roll (position accuracy, +/-2 m; pitch, roll, and heading accuracy, +/-0.02 degrees; heave accuracy, +/-5 percent, 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. Backscatter data from the 2006 and 2007 surveys (CSMP survey blocks CC-01, CC-02, CC-03, and CC-05) were processed using Geocoder Version 3.2 (Fugro Pelagos Modified Test Release 16). 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. After the lines were imported, they were mosaicked into a 1m resolution image. 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. Process_Date: 2007 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: USGS received original Caris HIPS and SIPS projects from CSUMB of the 2004-2005 multibeam survey of the Entrance to San Francisco Bay. USGS re-processed the backscatter data using Caris Hips and Sips (version 7.1) integration of Geocoder. 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. After the lines were imported, they were mosaicked into a 1m resolution image. 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. Process_Date: 2011 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Mercedes Erdey 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) 460-7416 Contact_Electronic_Mail_Address: merdey@usgs.gov Process_Step: Process_Description: California Seafloor Mapping Project 1- and 2-m resolution backscatter imagery (CSMP survey blocks CC-01, CC-02, CC-03, and CC-05) 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. Process_Date: 2011 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 Process_Step: Process_Description: Modified Distribution_Information section in metadata to facilitate data download. Process_Date: 20171005 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alan O. Allwardt Contact_Position: Contractor -- Information Specialist Contact_Address: Address_Type: mailing and physical address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7551 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: aallwardt@usgs.gov Process_Step: Process_Description: Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. Process_Date: 20171005 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alan O. Allwardt Contact_Position: Contractor -- Information Specialist Contact_Address: Address_Type: mailing and physical address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7551 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: aallwardt@usgs.gov Process_Step: Process_Description: Added keywords from Coastal and Marine Ecological Classification Standard (CMECS) to metadata. Process_Date: 20180426 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alan O. Allwardt Contact_Position: Contractor -- Information Specialist Contact_Address: Address_Type: mailing and physical address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7551 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: aallwardt@usgs.gov Process_Step: Process_Description: Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. Process_Date: 20201019 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road 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: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell 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 7125 acoustic-backscatter grid was originally archived as an ESRI grid with the following attributes: >Cell size = 2.0 >Number of rows = 8963 >Number of columns = 8960 > >Data type = floating point > >Boundary >Xmin = 531130 >Xmax = 549056 >Ymin = 4154950 >Ymax = 4172870 > >Statistics >Minimum value = 0 >Maximum value = 254 >Mean = 145.82 >Standard deviation = 27.53 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter 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 = 8963 >Number of columns = 8960 > >Data type = floating point > >Boundary >Xmin = 531130 >Xmax = 549056 >Ymin = 4154950 >Ymax = 4172870 > >Statistics >Minimum value = 1 >Maximum value = 254 >Mean = 141.60 >Standard deviation = 23.46 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter Entity_and_Attribute_Detail_Citation: none 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: Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by 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. Standard_Order_Process: Digital_Form: Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://pubs.usgs.gov/ds/781/ Fees: none Metadata_Reference_Information: Metadata_Date: 20201019 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