This layer is a georeferenced raster image containing shaded relief (hillshade) data for the offshore area of Coal Oil Point, California. The shaded relief map of the area was generated from data collected by California State University, Monterey Bay, Seafloor Mapping Lab (CSUMB), by the U.S. Geological Survey (USGS) and by Fugro Pelagos. . Most of the nearshore and shelf areas were mapped by the USGS in the summers of 2006, 2007, and 2008, using a combination of 117-kHz and 234.5-kHz SEA (AP) Ltd. SWATHplus-M phase-differencing sidescan sonars. A small area in the far-eastern nearshore and shelf was mapped by CSUMB in the summer of 2007, using a 244-kHz Reson 8101 multibeam echosounder. The outer shelf and slope were mapped by Fugro Pelagos in 2008, using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounders. The nearshore bathymetry and coastal topography were also mapped by Fugro Pelagos in 2009 for the U.S. Army Corps of Engineers (USACE) Joint Lidar Bathymetry Technical Center of Expertise, using the SHOALS-1000T bathymetric-lidar and the Leica ALS60 topographic-lidar systems. All of these mapping missions combined to collect bathymetry from the 0-m isobath to beyond the 3-nautical-mile limit of California's State Waters. NOTE: the horizontal datum of the bathymtry data (NAD83) differs from the horizontal datum of other layers in this SIM (WGS84). Some bathymetry grids within this map were projected horizontally from WGS84 to NAD83 using ESRI tools to be more consistent with the vertical reference of the North American Vertical Datum of 1988 (NAVD88). In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP) to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats and geology within the 3-nautical-mile limit of California's State Waters. CSMP has divided coastal California into 110 map blocks, each to be published individually as United States Geological Survey Open-File Reports (OFRs) or Scientific Investigations Maps (SIMs) at a scale of 1:24,000. Maps display seafloor morphology and character, identify potential marine benthic habitats and illustrate both the seafloor geology and shallow (to about 100 m) subsurface geology. Data layers for bathymetry, bathymetric contours, acoustic backscatter, seafloor character, potential benthic habitat and offshore geology were created for each map block, as well as regional-scale data layers for sediment thickness, depth to transition, transgressive contours, isopachs, predicted distributions of benthic macro-invertebrates and visual observations of benthic habitat from video cruises over the entire state. These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes.The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information. U.S. Geological Survey. (2013). Bathymetry Hillshade (2m): Offshore of Coal Oil Point, California, 2009. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/fh187gs5357. Information for the related USGS Pacific Coastal and Marine Science Center data collection field activities is available online: Z-2-06-SC, at http://walrus.wr.usgs.gov/infobank/z/z206sc/html/z-2-06-sc.meta.html; Z-1-07-SC, at http://walrus.wr.usgs.gov/infobank/z/z107sc/html/z-1-07-sc.meta.html; and S-8-08-SC, at http://walrus.wr.usgs.gov/infobank/s/s808sc/html/s-8-08-sc.meta.html. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.
