Metadata: Identification_Information: Citation: Citation_Information: Originator: Rikk Kvitek Originator: Guy R. Cochrane Publication_Date: 20240209 Title: Acoustic backscatter intensity from multibeam echosounder data collected offshore of Eureka, California Geospatial_Data_Presentation_Form: GeoTIFF Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9EC35PF Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, California Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9EC35PF Larger_Work_Citation: Citation_Information: Originator: Guy R. Cochrane Publication_Date: 2024 Title: Bathymetry, backscatter intensity, seismic reflection, and benthic habitat offshore of Eureka, California Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9EC35PF Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Other_Citation_Details: Suggested Citation: Cochrane, G.R., 2024, Bathymetry, backscatter intensity, seismic reflection, and benthic habitat offshore of Eureka, California, California: U.S. Geological Survey data release, https://doi.org/10.5066/P9EC35PF. Online_Linkage: https://doi.org/10.5066/P9EC35PF Description: Abstract: This 2-m-resolution acoustic backscatter data for the Offshore of Eureka, California, map area is part of USGS Data Series 781 (Golden and Cochrane, 2019). Backscatter data were collected by Fugro Pelagos in 2007 using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounder systems. The data were post-processed by the California State University Monterey Bay Seafloor Mapping. The acoustic backscatter data are available as a georeferenced TIFF image. 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: The surveys were conducted to map surficial geology and benthic habitat as part of the USGS California Seafloor Mapping Program, a collaboration with California State University Monterey Bay (CSUMB) and the National Oceanic and Atmospheric Administration (NOAA) funded by the California Ocean Protection Council. These data are intended to provide regional bathymetric information in California State waters for offshore resource and ecosystem management. These data are also intended for science researchers, students, policy makers, and the general public. These data can be used with geographic information systems or other software to help identify geomorphologic features and surficial lithology. These data are not intended to be used for navigation. Supplemental_Information: Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2007 Currentness_Reference: ground condition at time data were collected. Status: Progress: Complete Maintenance_and_Update_Frequency: none planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -124.367691 East_Bounding_Coordinate: -124.149 North_Bounding_Coordinate: 40.849276 South_Bounding_Coordinate: 40.6878 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:21509a68-ab9d-460a-bb59-527dab5fb252 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: sea-floor characteristics Theme_Keyword: sea-floor acoustic reflectivity Theme_Keyword: geospatial datasets Theme_Keyword: marine geophysics Theme_Keyword: multibeam sonar Theme_Keyword: image mosaics Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: Substrate Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: seabed Theme_Keyword: field observation Theme: Theme_Keyword_Thesaurus: none Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: PCMSC Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: State of California Place_Keyword: Eureka Place_Keyword: Humboldt County Access_Constraints: None Use_Constraints: USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey and the California State University Monterey Bay Seafloor Mapping Lab as the originators of the dataset and in products derived from these data. This information is not intended for navigation purposes. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: Backscatter_OffshoreEureka.jpg Browse_Graphic_File_Description: Preview image of the backscatter-intensity data offshore of Eureka Browse_Graphic_File_Type: JPEG Data_Set_Credit: Data acquisition was a joint effort between the U.S. Geological Survey, California State University Monterey Bay, and Humboldt State University. The authors acknowledge the crew of Humboldt State University’s R/V Coral Sea and all those involved in in survey planning and execution. Funding was provided by the California Ocean Protection Council Cochrane, G.R., 2024, Bathymetry, backscatter intensity, seismic reflection, and benthic habitat offshore of Eureka, California, California: U.S. Geological Survey data release, https://doi.org/10.5066/P9EC35PF Native_Data_Set_Environment: Caris HIPS, ArcGIS (ver. 10.8.2), Windows 10. Cross_Reference: Citation_Information: Originator: Nadine E. Golden Originator: Guy R. Cochrane Publication_Date: 2019 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 Other_Citation_Details: Golden N.E. and Cochrane, G.R., compiler, 2019, California State Waters Map Series Data Catalog, https://doi.org/10.3133/ds781. Online_Linkage: https://doi.org/10.3133/ds781 Cross_Reference: Citation_Information: Originator: California State University, Monterey Bay, Seafloor Mapping Lab Publication_Date: 2016 Title: Northern California 2007 CSMP surveys: California State University, Monterey Bay, Seafloor Mapping Lab Data Library Other_Citation_Details: California State University, Monterey Bay, Seafloor Mapping Lab, 2016, Southern California 2008 CSMP surveys: California State University, Monterey Bay, Seafloor Mapping Lab Data Library Online_Linkage: http://seafloor.otterlabs.org/SFMLwebDATA_SURVEYMAP.htm Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Not applicable for raster data. Logical_Consistency_Report: No formal logical accuracy tests were conducted. Completeness_Report: Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The POS MV position and motion compensation system has a horizontal positional accuracy of about 0.5 m with DGPS corrections and roll and pitch accuracies of about 0.02 degrees (http://www.measutronics.com/wp-content/uploads/2011/01/posmv320_specifications.pdf). Accuracies of final products may be lower due 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. Lineage: Process_Step: Process_Description: Multibeam echosounder (MBES) data were collected by Fugro Pelagos in 2007 using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounders. An Applanix POS-MV (Position and Orientation System for Marine Vessels) was used to accurately position the vessels during data collection, and it also accounted for vessel motion such as heave, pitch, and roll, with navigational input from GPS receivers. Smoothed Best Estimated Trajectory (SBET) files were postprocessed from logged POS-MV files. Sound-velocity profiles were collected with an Applied Microsystems (AM) 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) and heave using the postprocessed SBET data (California State University, Monterey Bay, Seafloor Mapping Lab, 2016). The Reson backscatter data were postprocessed using Geocoder software. 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 on a line-by-line basis. After the lines were corrected, they were mosaicked into 0.5-m resolution images (California State University, Monterey Bay, Seafloor Mapping Lab, 2016). Process_Date: 2016 Process_Step: Process_Description: The 0.5-m-resolution images were mosaiced and clipped to the study area boundary by the USGS. The mosaics were then exported as 2-m resolution georeferenced TIFF images. Process_Date: 2023 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 9095 Column_Count: 9100 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: 10.0 Ordinate_Resolution: 10.0 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: D_WGS_1984 Ellipsoid_Name: WGS_844 Semi-major_Axis: 6378137.00 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: value Entity_Type_Definition: backscatter intensity as a digital value Entity_Type_Definition_Source: Producer defined Overview_Description: Entity_and_Attribute_Overview: The complete 2-m resolution Offshore of Eureka backscatter raster is an 8-bit integer raster. It has a minimum (least reflective) value of 1 and a maximum (most reflective) value of 254. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - CMGDS Contact_Address: Address_Type: Mailing and Physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Resource_Description: These data are available in GeoTIFF format (Backscatter_OffshoreEureka.tif), along with a tif world file (.tfw) and CSDGM FGDC-compliant metadata. 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_Information: Format_Name: GeoTIFF Format_Version_Number: ArcMap (version 10.8.2) Format_Information_Content: Downloadable zip file contains the GeoTIFF (.tif), and the projection file (.tfw). File_Decompression_Technique: Windows 10 Zip Transfer_Size: 36.8 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P9EC35PF Network_Resource_Name: https://doi.org/10.3133/ds781 Access_Instructions: The backscatter data can be downloaded by going to the first Network_Resource_Name link, then scrolling down to the Multibeam Data section. The second link points to a landing page for the entire California State Waters Map Series Data Catalog. Fees: None Technical_Prerequisites: The downloadable data file has been compressed with the Windows 10 "zip" command and can be unzipped using Windows File Explorer or with Winzip (or other tools). To utilize these data, the user must have software capable importing and viewing a GeoTIFF file. Metadata_Reference_Information: Metadata_Date: 20240213 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998