Guy R. Cochrane 20230930 vector digital data data release DOI:10.5066/P902YIF5 Pacific Coastal and Marine Science Center, Santa Cruz, California U.S. Geological Survey https://doi.org/10.5066/P902YIF5 Guy R. Cochrane 2023 data release DOI:10.5066/P902YIF5 Reston, VA U.S. Geological Survey Suggested Citation: Cochrane, G.R., 2023, Bathymetry, backscatter intensity, and benthic habitat offshore of the Eel River, California: U.S. Geological Survey data release, https://doi.org/10.5066/P902YIF5. https://doi.org/10.5066/P902YIF5 This part of USGS Data Series 781 presents substrate, geomorphic, and geologic attributed polygons in the Offshore of the Eel River, California, map area, one of 83 map areas of the California State Waters Map Series. The polygons are derived from multibeam echosounder (MBES) data and derivatives of that data using video-supervised and unsupervised classification. Attributes and attribute values are named following the Coastal and Marine Ecological Classification Standard (CMECS; Federal Geographic Data Committee, 2012) to be useful for ecosystems management. To expand geologic mapping to the seafloor within California's State Waters, to update coastal habitat mapping, and to contribute to a uniform regional habitat database. Additionally, to provide a habitat map for the public and Eco-science community to aid in land-use and land-management decisions both onshore and offshore. Additional information about the USGS field activities from which some of these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=C210NC 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. 2011 ground condition Complete none planned -124.541854 -124.372596 40.539173 40.37681 USGS Metadata Identifier USGS:3556f563-b984-41b6-bf06-516b8aaaec6b ISO 19115 Topic Category geoscientificInformation environment oceans imageryBaseMapsEarthCover Data Categories for Marine Planning Physical Habitats and Geomorphology Habitat Invertebrates Biodiversity USGS Thesaurus sea-floor characteristics Marine Realms Information Bank (MRIB) keywords seabed field observation None U.S. Geological Survey USGS Coastal and Marine Hazards and Resources Program CMHRP Pacific Coastal and Marine Science Center PCMSC Geographic Names Information System (GNIS) Eel River State of California Humboldt County 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 as the originator 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 831-427-4747 pcmsc_data@usgs.gov CMECS_OffshoreEelRiver.jpg Preview image of CMECS benthic habitat data offshore of the Eel River JPEG ArcGIS 10.8.2, Windows 10 Nadine Golden 2019 database Data Series DS 781 Reston, VA U.S. Geological Survey Golden, N.E., compiler, 2019, California State Waters Map Series Data Catalog, https://doi.org/10.3133/ds781 https://doi.org/10.3133/ds781. Federal Geographic Data Committee 2012 Federal Geographic Data Committee, 2012, Coastal and Marine Ecological Classification Standard, 343 p. https://www.fgdc.gov/standards/projects/cmecs-folder/CMECS_Version_06-2012_FINAL.pdf Guy R. Cochrane 2008 Cochrane, G.R., 2008, Video-supervised classification of sonar data for mapping seafloor habitat, in Reynolds, J.R., and Greene, H.G., eds., Marine habitat mapping technology for Alaska: Fairbanks, University of Alaska, Alaska Sea Grant College Program, p. 185-194. https://seagrant.uaf.edu/lib/aksg/0803/mhmta-cochrane.pdf R.J. McLaughlin, S.D. Ellen M.C. Blake, Jr. A.S. Jayko W.P. Irwin K.R. Aalto G.A. Carver S.H. Clarke Jr. 2000 R.J. McLaughlin, S.D. Ellen, M.C. Blake, Jr., A.S. Jayko, W.P. Irwin, K.R. Aalto,G.A. Carver, and S.H. Clarke, Jr., 2000, USGS Miscellaneous Field Studies MF-2336. https://pubs.usgs.gov/mf/2000/2336/ Polygons were derived using video supervised classification and unsupervised classification, and attribute values assigned to polygons are based in part on geologic interpretation; the accuracy of the attribute values and of substrate observations from video cannot be quantified. Polygons were visually checked for overshoots, undershoots, duplicate features, polygon closure, and other errors by the lead author and by the GIS technicians who created the digital database. No checks for consistency were performed on this data. Data are complete, in the conversion of rasters with 2-m resolution some small areas were eliminated by filtering to reduce the number of small polygons. The smallest area represented is approximately 0.5 square meters. All geospatial database elements are attributed. Polygons were mapped by numerical classification of 2-meter-resolution backscatter intensity, and derivatives of bathymetry data, and from visual observations of underwater sea floor video. Sea floor video information position accuracies are highly variable, on the order of 10 meters. Horizontal position given is ship position. A towed camera can be on the order of 10 meters distance from the ship during deployment. MBES data have a horizontal accuracy of approximately 2 meters in continental shelf depths. A horizontal accuracy of polygon boundaries cannot be quantified. Mosaics of bathymetry and backscatter intensity data for the map area were created from component surveys conducted by Fugro Pelagos Inc. and the California Seafloor Mapping Lab at California State University Monterey Bay in 2005. 2023 Seafloor induration was derived from the backscatter intensity and derived ruggedness rasters using the video-supervised method of Cochrane (2008). The CMECS Substrate Induration values are described in Federal Geographic Data Committee (2012). 2023 The seafloor induration raster was combined with a CMECS slope class raster, a bathymetry index raster and a CMECS depth zone raster resulting in 62 unique classes of seafloor. The raster was filtered to reduce the number of small areas and converted to polygons. The resulting shapefile has a few geoforms that were classified by hand in places where geologic interpretation was used. 2023 Vector GT-polygon composed of chains 6178 Universal Transverse Mercator 10 0.9996 -123.00000 0.00000 500000.0 0.00 coordinate pair 10.0 10.0 Meters D_WGS_1984 WGS_844 6378137.00 298.257223563 Polygon Polygons representing geologic/geomorphic map units This report FID Internal feature number. Esri 0 6177 Shape feature type Esri polygon type vector object Shape_Area Area of polygon in square meters ESRI 4.0 19287000.0 meters 0.00001 SubInd substrate induration class CMECS Hard rugged bedrock areas CMECS Mixed flat coarse sediment and bedrock areas CMECS Soft flat fine grained sedimented areas CMECS Slope CMECS slope class CMECS Flat seafloor area sloping 0 to 5 degrees CMECS Sloping seafloor area sloping 5 to 30 degrees CMECS BPI bathymetry position index class Guy R. Cochrane Convex area with BPI values less than -0.000001 Guy R. Cochrane Flat areas with BPI values between 0.000001 and -0.000001 Guy R. Cochrane DepthZone ocean depth zones CMECS Circalittoral depths ranging from 30 to 200 meters CMECS Deep Infralittoral depths from 5 to 30 meters CMECS Modifier CMECS code for modifier values CMECS SI1S1BDZ3 substrate induration 1, slope 1, benthic depth zone 3 CMECS SI1S2BDZ3 substrate induration 1, slope 2, benthic depth zone 3 CMECS SI2S1BDZ3 substrate induration 2, slope 1, benthic depth zone 3 CMECS SI2S1BDZ4 substrate induration 2, slope 1, benthic depth zone 4 CMECS SI2S2BDZ3 substrate induration 2, slope 2, benthic depth zone 3 CMECS SI3S1BDZ3 substrate induration 3, slope 1, benthic depth zone 3 CMECS SI3S1BDZ4 substrate induration 3, slope 1, benthic depth zone 4 CMECS SI3S2BDZ3 substrate induration 3, slope 2, benthic depth zone 3 CMECS ModDesc description of modifier codes CMECS Hard flat bottom at deep infralittoral depth definition of code SI1S1BDZ3 CMECS Hard sloping bottom at deep infralittoral depth definition of code SI1S2BDZ3 CMECS Mixed flat bottom at circalittoral depth definition of code SI2S1BDZ4 CMECS Mixed flat bottom at deep infralittoral depth definition of code SI2S1BDZ3 CMECS Mixed sloping bottom at deep infralittoral depth definition of code SI2S2BDZ3 CMECS Soft flat bottom at circalittoral depth definition of code SI1S1BDZ4 CMECS Soft flat bottom at deep infralittoral depth definition of code SI3S1BDZ3 CMECS Soft sloping bottom at deep infralittoral depth definition of code SI3S2BDZ3 CMECS Geoform geoform code for polygon CMECS Gt2p6 convergent active margin tectonic setting, continental shelf physiographic setting, depression geoform CMECS Gt2p6g14.1 convergent active margin tectonic setting, continental shelf physiographic setting, scour depression geoform CMECS Gt2p6g48 convergent active continental margin tectonic setting, continental shelf physiographic setting, ridge geoform CMECS Gt2p6g50 convergent active continental margin tectonic setting, continental shelf physiographic setting, rock outcrop geoform CMECS Gt2p6g61 convergent active continental margin tectonic setting, continental shelf physiographic setting, slope geoform CMECS GeofrmDesc description of geoform CMECS Ridge a convex linear hard- or mixed-bottom feature CMECS Rock outcrop an exposure of bedrock on the seafloor CMECS Scour depression shallow depressed area of coarse sediment and flat bedrock formed by bottom current winnowing of shelf sediment CMECS Shelf flat sediment covered continental shelf CMECS Slope sloping or steeply sloping area on the shelf CMECS Geology geologic unit Guy R. Cochrane Qms Marine nearshore and shelf deposits (late Holocene); mostly sand; ripples common Guy R. Cochrane Qmsc Coarse-grained marine nearshore and shelf deposits (late Holocene); Coarse sand and gravel to boulders Guy R. Cochrane Qmsd Marine shelf scour depressions (Holocene); Inferred to be coarse sand and gravel, in low-relief scour depressions Guy R. Cochrane Qmsf Fine-grained marine shelf deposits (Holocene); Mostly mud, and fine sand Guy R. Cochrane fc Sedimentary rocks of the False Cape terrane McLaughlin, R.J., and others, 2000 GeolgyDesc geologic unit description Guy R. Cochrane Holocene coarse sand and gravel abbreviated description of geologic unit Qmsd Guy R. Cochrane Holocene coarse sand and possible gravel abbreviated description of geologic unit Qmsc Guy R. Cochrane Holocene mud and fine sand abbreviated description of geologic unit Qmsf Guy R. Cochrane Late Holocene sand commonly rippled abbreviated description of geologic unit Qms Guy R. Cochrane Sedimentary rocks of the False Cape terrane abbreviated description of geologic unit fc McLaughlin, R.J., and others, 2000 Substrate substrate code for polygon CMECS S1.1.1 Bedrock CMECS S1.2.1.3.1 Gravelly sand CMECS S1.2.2.2 Sand CMECS S1.2.2.4 Sandy mud CMECS shapefile consisting of 6178 polygons classified into 11 CMECS geoforms Federal Geographic Data Committee, 2012, Coastal and Marine Ecological Classification Standard, 343 p., accessed March 10, 2022, at https://www.fgdc.gov/standards/projects/cmecs-folder/CMECS_Version_06-2012_FINAL.pdf U.S. Geological Survey - CMGDS Mailing and Physical

2885 Mission Street

Santa Cruz CA 95060 831-427-4747 pcmsc_data@usgs.gov These data are available in shapefile format (CMECS_OffshoreEelRiver.shp and associated files) contained in a single zip file (CMECS_OffshoreEelRiver.zip). 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. shapefile ArcGIS 10.8.2 Esri polygon shapefile Zip file contains the polygon shapefile No compression applied 0.6 https://doi.org/10.5066/P902YIF5 https://doi.org/10.3133/ds781 The data can be downloaded by going to the first Network_Resource_Name link, then scrolling down to the Habitat Data section. The second link points to a landing page for the entire California State Waters Map Series Data Catalog. None. These data can be viewed with GIS software. 20230930 U.S. Geological Survey, Pacific Coastal and Marine Science Center PCMSC Science Data Coordinator mailing and physical

2885 Mission Street

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