Edward M. Sweeney 2004 1.0 raster digital data Open-File Report 2004-1082 Woods Hole Coastal and Marine Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.3133/ofr20041082 https://pubs.usgs.gov/of/2004/1082/html/META.htm https://pubs.usgs.gov/of/2004/1082/arcgis/mosaic/farallones_tiff.zip Edward M. Sweeney William W. Danforth Herman A. Karl Thomas F. O'Brien William C. Schwab 2004 1.0 Open-File Report 2004-1082 Woods Hole Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.3133/ofr20041082 https://pubs.usgs.gov/of/2004/1082/ In 1989, the U.S. Geological Survey (USGS) began a major geologic and oceanographic investigation of the Gulf of the Farallones continental shelf system, designed to evaluate and monitor human impacts on the marine environment (Karl and others, 2002). The study region is located off the central California coast, adjacent to San Francisco Bay and encompasses the Gulf of the Farallones National Marine Sanctuary. Geologic mapping of this area included the use of various remote sensing and sampling techniques such as sub-bottom profiling, sidescan-sonar and bathymetric mapping, gravity core and grab sampling, and photography. These data were used to define the surficial sediment distribution, underlying structure and sea floor morphology of the study area. The primary focus of this report is to present a georeferenced, digital sidescan-sonar mosaic of the study region. The sidescan-sonar data were acquired with the AMS-120 (120kHz) sidescan-sonar system during USGS cruise F9-89-NC. The dataset covers approximately 1000 km2 of the continental shelf between Point Reyes, California and Half Moon Bay, California, extending west to the continental shelf break near the Farallon Islands. The sidescan-sonar mosaic displays a heterogenous sea-floor environment, containing outcropping rock, ripples, dunes, lineations and depressions, as well as flat, featureless sea floor (Karl and others, 2002). These data, along with sub-bottom interpretation and ground truth data define the geologic framework of the region. The sidescan-sonar mosaic can be used with supplemental remote sensing and sampling data as a base for future research, helping to define the local current regime and predominant sediment transport directions and forcing conditions within the Gulf of Farallones. These data were acquired during the sidescan-sonar survey completed in the Gulf of the Farallones in August, 1989 by the U.S. Geological Survey and were used to define the geological framework of the region. 19890802 19890815 ground condition Complete None planned -123.398630 -122.674261 37.998062 37.550340 USGS Metadata Identifier USGS:1eebb3c3-8192-4a19-8e29-ad041e8ae210 None sonar Sidescan-sonar backscatter USGS U.S. Geological Survey Coastal and Marine Geology Program CMGP field activity identifier F9-89-NC field activity serial number 89020 Woods Hole Science Center imagery AMS-120 seafloor mapping grey-scale image GeoTIFF ISO 19115 Topic Category oceans imageryBaseMapsEarthCover geoscientificInformation Data Categories for Marine Planning distributions physical habitats and geomorphology Marine Realms Information Bank (MRIB) Keywords seabed sidescan sonar marine geophysics USGS Thesaurus sidescan sonar image mosaics marine geophysics sea-floor characteristics sea-floor acoustic reflectivity None Gulf of the Farallones Farallones California U.S. West Coast U.S. Pacific Coast North America Pacific Ocean United States Half Moon Bay Point Reyes Farallon Islands Bodega Bay San Francisco None Public domain data from the U.S. government is freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of this dataset. Edward M. Sweeney U.S. Geological Survey Research Assistant mailing and physical address

384 Woods Hole Rd.

Woods Hole MA 02543-1598 USA (508) 548-8700 (508) 457-2310 https://pubs.usgs.gov/of/2004/1082/html/pdf/FIG5.pdf Map showing sidescan-sonar mosaic of the Gulf of the Farallones. PDF Microsoft Windows 2000 Version 5.1 (Build 2600) Service Pack 1; ESRI ArcCatalog 8.3.0.800 These data were acquired with an AMS-120 (120 kHz) sidescan-sonar system. All data were acquired during one geophysical cruise condcuted in 1989. These data were navigated using GPS and LORAN-C. The horizontal accuracy of these data is roughly +/- 50 meter. Additionally, no layback was estimated for the tow-vehicle. Thus, navigation was based on ship position and not tow-vehicle posistion. Thus, decreasing the horizontal positioning resolution of these data. These data were acquired with an AMS-120 (120 kHz) sidescan-sonar system, and processed following an identical procedure. This mosaic contains all the collected sidescan sonar data and is complete. The sidescan-sonar data were acquired using an AMS-120 (120 kHz) sidescan-sonar system. The analog signal from the sidescan-sonar tow vehicle was aquired with and stored on a Triton Technologies, Inc. QMIPS data acquisition system, and then transferred to a Masscomp computer and stored on 8mm 54 MB digital data cartridge tapes. Radiometric corrections and geometric distortions were made using USGS software packages Xsonar and Showimage described in Danforth and others (1991) and Danforth (1997). The sidescan-sonar data were further processed and digitally mosaicked using PCI Geomatica Software and procedures described in Paskevich (1992) resulting in an enhanced, geospatially correct, sidescan-sonar mosaic with 4 meter/pixel resolution. The generated mosaic was exported as a TIFF image, with an associated ESRI world file. Adjustment in contrast levels were then made on the TIFF image file using Adobe Photoshp 6.0. 2004 Edward M. Sweeney U.S. Geological Survey Research Assistant mailing and physical address

384 Woods Hole Rd.

Woods Hole MA 02543 USA (508) 548-8700 x2307 (508) 457-2310 esweeney@usgs.gov Edits to the metadata were made to fix any errors that MP v 2.9.34 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent. 20161114 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. 20170214 U.S. Geological Survey Alan O. Allwardt Contractor -- Information Specialist Mailing and Physical

2885 Mission Street

Santa Cruz CA 95060 831-460-7551 831-427-4748 aallwardt@usgs.gov Crossref DOI link was added as the first link in the metadata. 20191118 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Added keywords section with USGS persistent identifier as theme keyword (20200908). Removed links to a server Coastalmap that is no longer available (20230628). 20230628 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Raster Pixel 12400 15900 1 Universal Transverse Mercator 10 0.999600 -123.000000 0.000000 500000.000000 0.000000 row and column 4.000000 4.000000 meters D_WGS_1984 WGS_1984 6378137.000000 298.257224 There are no attributes associated with the GeoTIFF or MrSID image. U.S. Geological Survey U.S. Geological Survey mailing and physical address

384 Woods Hole Rd.

Woods Hole MA 02543-1598 USA (508) 548-8700 (580) 457-2310 Downloadable Data Although this data set and its lineage have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data or its 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 items. Users must assume responsibility for the proper use of these data. The data should not be used at resolutions for which they are not intended. The data have not been reviewed for conformity with U.S. Geological Survey editorial standards, or the North American Strigraphic code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government. TIFF Information unavailable from original metadata. GeoTIFF A zip archive containing the GeoTIFF image, associated world file, and metadata. zip archive 48.4 https://pubs.usgs.gov/of/2004/1082/arcgis/mosaic/farallones_tiff.zip Data may be retrieved via any WWW browser. None This image is available as a GEOTIFF 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 GEOTIFF image. U.S. Geological Survey mailing and physical address

384 Woods Hole Road

Woods Hole MA 02543-1598 USA (508) 548-8700 (508) 457-2310 Downloadable Data Although this data set and its lineage have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data or its 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 items. Users must assume responsibility for the proper use of these data. The data should not be used at resolutions for which they are not intended. The data have not been reviewed for conformity with U.S. Geological Survey editorial standards, or the North American Strigraphic code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government. SID Information unavailable from original metadata. MrSID A zip archive containing the MrSID image, associated world file, and metadata. zip archive 8 https://pubs.usgs.gov/of/2004/1082/arcgis/mosaic/farallones_sid.zip Data may be retrieved via any WWW browser. None This image is available in a MrSID format 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. 20230628 Edward M. Sweeney U.S. Geological Survey Research Assistant mailing and physical address

384 Woods Hole Rd.

Woods Hole MA 02543-1598 USA (508) 548-8700 (508) 457-2310 whsc_data_contact@usgs.gov The metadata contact email address is a generic address in the event the metadata contact is no longer with the USGS FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time