Peter Dartnell Andrew C. Ritchie David P. Finlayson Rikk G. Kvitek 2015 1.0 GeoTiff Data Series DS 781 Reston, VA U.S. Geological Survey https://www.sciencebase.gov/catalog/item/555fa9b3e4b0afeb70723eec Nadine E. Golden 2015 database Data Series DS 781 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ds781 https://cmgds.marine.usgs.gov/data/csmp/OffshoreScottCreek/data_catalog_OffshoreScottCreek.html This part of DS 781 presents data for the acoustic-backscatter map of Offshore of Scott Creek map area, California. Backscatter data are provided as three separate grids depending on mapping system. The raster data files are included in "BackscatterB_7125_OffshoreScottCreek.zip," which is accessible from https://doi.org/10.5066/F7CJ8BJW. These data accompany the pamphlet and map sheets of Cochrane, G.R., Dartnell, P., Johnson, S.Y., Greene, H.G., Erdey, M.D., Dieter, B.E., Golden, N.E., Endris, C.A., Hartwell, S.R., Kvitek, R.G., Davenport, C.W., Watt, J.T., Krigsman, L.M., Ritchie, A.C., Sliter, R.W., Finlayson, D.P., and Maier, K.L. (G.R. Cochrane and S.A. Cochran, eds.), 2015, California State Waters Map Series--Offshore of Scott Creek, California: U.S. Geological Survey Open-File Report 2015-1191, pamphlet 40 p., 10 sheets, scale 1:24,000, http://doi.org/10.3133/ofr20151191. The acoustic-backscatter map of the Offshore of Scott Creek map area, California, was generated from backscatter data collected by California State University, Monterey Bay (CSUMB), by Fugro Pelagos, and by the U.S. Geological Survey (USGS). Mapping was completed between 2006 and 2009, using a combination of 400-kHz Reson 7125 (CSUMB) and 244-kHz Reson 8101 (FUGRO) multibeam echosounders, as well as a 234-kHz SWATHplus bathymetric sidescan-sonar system (USGS). These mapping missions combined to collect backscatter data from about the 10-m isobath to beyond the 3-nautical-mile limit of California's State Waters. 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). 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 to identify seafloor features. 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. 2006 2009 ground condition Complete As needed -122.39 -122.19 37.10 36.94 USGS Metadata Identifier USGS:555fa9b3e4b0afeb70723eec Global Change Master Directory (GCMD) Acoustic Reflectivity None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Fisheries Backscatter Intensity Seafloor Character ISO 19115 Topic Category geoscientificInformation environment oceans imageryBaseMapsEarthCover Data Categories for Marine Planning distributions physical habitats and geomorphology Marine Realms Information Bank (MRIB) keywords seabed sidescan sonar marine geophysics USGS Thesaurus geology bathymetry ecosystems multibeam sonar sonar methods sidescan sonar image mosaics marine geophysics sea-floor characteristics sea-floor acoustic reflectivity maps and atlases geospatial datasets Coastal and Marine Ecological Classification Standard (CMECS) Marine Nearshore Subtidal Marine Offshore Subtidal Transform Continental Margin Continental/Island Shelf Rock Substrate Unconsolidated Mineral Substrate Geographic Names Information System (GNIS) Pacific Ocean State of California Scott Creek Santa Cruz County Coastal and Marine Ecological Classification Standard (CMECS) Northern California Ecoregion Coastal and Marine Ecological Classification Standard (CMECS) Substrate None 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 California State University Monterey Bay as the originator(s) of the dataset and in products derived from these data. U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060-5792 US 831-427-4747 pcmsc_data@usgs.gov https://www.sciencebase.gov/catalog/file/get/556618fde4b0d9246a9ec12c?name=BackscatterB_7125_OffshoreScottCreek.jpg&allowOpen=true Acoustic backscatter imagery of Offshore of Scott Creek, California, map area. JPEG Microsoft Windows Server 2008 R2 Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 10.0 Guy R. Cochrane Peter Dartnell Samuel Y. Johnson H. Gary Greene Mercedes D. Erdey Bryan E. Dieter Nadine E. Golden Charles A. Endris Stephen R. Hartwell Rikk G. Kvitek Clifton W. Davenport Janet T. Watt Andrew C. Ritchie Ray W. Sliter David P. Finlayson Katherine L. Maier 2015 map Open-File Report 2015-1191 Reston, VA U.S. Geological Survey https://doi.org/10.3133/ofr20151191 Not applicable for raster data. Unspecified Complete 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. Not applicable to acoustic-backscatter imagery. During the CSUMB and Fugro Pelagos mapping missions, 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 (position accuracy, ±2 m; pitch, roll, and heading accuracy, ±0.02°; heave accuracy, ±5%, or 5 cm). To account for tidal-cycle fluctuations, RTK data(GPS data with real-time kinematic corrections) was used; in addition, 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) using vertical-position data from the RTK receivers. Processing and mosaicking of Reson 7125 backscatter data were completed using GEOCODER Version 3.2 level 1 (created by Luciano Fonseca; 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 and georeferenced to UTM Zone 10 N, WGS1984 datum. After the lines were imported, they were mosaicked into a 1-m-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. 2007 Carrie Bretz Seafloor Mapping Lab, California State University Monterey Bay Projects Manager, GIS; Metadata Supervisor mailing and physical address

100 Campus Center, Bldg 13

Seaside CA 93955 USA (831) 582-4197 carrie_bretz@csumb.edu California Seafloor Mapping Project 1- and 2-m-resolution backscatter imagery (CSMP survey block CC-11) 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 and can be found in different zip files within the Offshore of Scott Creek data release. 2014 Pete Dartnell U.S. Geological Survey, Pacific Coastal and Marine Science Center Physical Scientist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060-5792 USA (831) 460-7415 pdartnell@usgs.gov Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. 20171005 U.S. Geological Survey Alan O. Allwardt Contractor -- Information Specialist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060 831-460-7551 831-427-4748 aallwardt@usgs.gov Added keywords from Coastal and Marine Ecological Classification Standard (CMECS) to metadata. 20180426 U.S. Geological Survey Alan O. Allwardt Contractor -- Information Specialist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060 831-460-7551 831-427-4748 aallwardt@usgs.gov Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. 20201019 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 Edits were made to bring the metadata up to current PCMSC standards including standardizing authors' names, adding a doi# link, correcting typos, refining keywords, and using current access and distribution liability statements. Point of Contact and Metadata Contact information sections were changed to static PCMSC contact information. No data were changed. The metadata available from a harvester may supersede metadata bundled within a download file. Users are advised to compare the metadata date of this file to any similar file to ensure they are using the most recent version. 20211124 U.S. Geological Survey Susan A. Cochran Geologist Mailing and Physical

2885 Mission Street

Santa Cruz CA 95060 831-460-7545 scochran@usgs.gov Raster Grid Cell 8890 8890 1 Universal Transverse Mercator 10 0.9996 -123.00000 0.00000 500000.0 0.00 coordinate pair 2.0 2.0 Meters WGS84 WGS84 6378137.00 298.257223563 Value BackscatterA [8101] intensity value ESRI Rowid Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. VALUE Backscatter intensity values ESRI 0.0 254.0 Integers representing intensity values COUNT The number of pixels (2m x 2m size grid cell) represented in each intensity value (see Attribute: VALUE). ESRI 14 52992 Integers 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 = 8840 >Number of columns = 8870 > >Data type = floating point > >Boundary >Xmin = 554460 >Xmax = 572200 >Ymin = 4088870 >Ymax = 4106550 > >Statistics >Minimum value = 0 >Maximum value = 254 >Mean = 174.80 >Standard deviation = 25.63 > >Coordinate system description >Projection UTM >Zone 10 >Datum WGS84 >Units meter none U.S. Geological Survey - ScienceBase mailing and physical

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov The .zip file (BackscatterB_7125_OffshoreScottCreek.zip) includes the .tfw, .tif, .tif.aux.xml, and .tif.ovr files, as well as FGDC-compliant metadata for the BackscatterB [7125] data layer in the Offshore Scott Creek region of California. 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. TIFF ArcMap (version 10.0, ESRI , 2011) Raster data layer is registered TIFF image in the UTM Zone 10 coordinate system with datum WGS84. 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 [7125] data layer of Offshore Scott Creek, California. WinZip 3.5 https://www.sciencebase.gov/catalog/file/get/555fa9b3e4b0afeb70723eec https://cmgds.marine.usgs.gov/data/csmp/OffshoreScottCreek/data_catalog_OffshoreScottCreek.html https://doi.org/10.3133/ds781 The first link will begin a direct download of the data. The second link is a landing page on which all of the downloadable data for a particular region are listed. The third link is a landing page for the entire data catalog. none 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, OffshoreScottCreekGIS.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 Scott Creek" 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. 20211124 U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

Santa Cruz CA 95060-5792 US 831-427-4747 pcmsc_data@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time