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Title: Contours (10m): Offshore of San Gregorio, California, 2007

• Bretz, Carrie K.
• Kvitek, Rikk G.
• Cochrane, Guy R.
• Dartnell, Peter
• Johnson, Samuel Y.
• Golden, Nadine E.
• Fugro Pelagos, Inc
• Seafloor Mapping Lab
• Pacific Coastal and Marine Science Center

Dates

• Issued: 2013
• Coverage: 2013

Publishers

• Geological Survey (U.S.)

Summary

This line shapefile contains bathymetric contours at 10 meter intervals for the offshore area of San Gregorio, California. This layer was generated from bathymetry data collected by Fugro Pelagos and by California State University, Monterey Bay, Seafloor Mapping Lab (CSUMB). Mapping was completed in 2006 and 2007, using a combination of 400-kHz Reson 7125 and 244-kHz Reson 8101 multibeam echosounders. These mapping missions combined to collect bathymetry from about the 10-m isobath to beyond the 3-nautical-mile limit of California's State Waters. Bathymetric contours at 10-m intervals were generated from the merged 2-m bathymetric surface. The most continuous contour segments were preserved while smaller segments and isolated island polygons were excluded from the final output. Contours were smoothed via a polynomial approximation with exponential kernel (PAEK) algorithm using a tolerance value of 60 m. The contours were then clipped to the boundary of the map area. A map that shows these data is published in Scientific Investigations Map 3306, "California State Waters Map Series--Offshore of San Gregorio, California." This layer is part of USGS Data Series 781. 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. Part of the marine habitat mapping data for the California North Central Coast Mapping Project (NCCMP), this coverage can be used to to aid in assessments and mitigation of geologic hazards in the coastal region and to provide sufficient geologic information for land-use and land-management decisions both onshore and offshore. 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). Contours (10m): Offshore of San Gregorio, California, 2007. California State Waters Map Series Data Catalog: U.S. Geological Survey Data Series 781. Available at: http://purl.stanford.edu/fh627vx6058. MBES and side scan data for CC_Block01 to CC_Block11 are a combination of 400KHz Reson 7125 and 244 KHz Reson 8101 sonar data collected aboard the F/V Quicksilver by Fugro Pelagos, Inc. (FPI) and the R/V VenTresca by the Seafloor Mapping Lab (SFML). CC_Block00 (Stinson Beach) and the area surrounding the San Francisco Bay mouth were surveyed entirely by SFML using the Reson 8101 aboard the VenTresca. Prior to data collection, a series of planned survey lines were created using the survey navigation and planning softwareWinFrog (FPI) or Hypack Max GOLD from Hypack, Inc (SFML). An Applanix POS/MV system with TrueHeave processing was used to provide position and attitude data for each vessel during data collection and accounted for vessel motion such as heave, pitch, and roll (position accuracy ± 2m, pitch, roll and heading accuracy ±0.02°, heave accuracy ± 5% or 5cm). KGPS altitude data were used to account for tide cycle fluctuations and sound velocity profiles were collected with an Applied Microsystems SVPlus sound velocimeter. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

Subjects

• Oceans
• Elevation
• California
• San Mateo County (Calif.)
• Pacific Ocean
• Coasts
• Contours (Cartography)
• Ocean bottom
• Geoscientific Information
• Datasets

Geospatial coordinates

• Bounding Box: BBOX (-122.490646, -122.409526, 37.391501, 37.229801)
• Geometry: BBOX (-122.490646, -122.409526, 37.391501, 37.229801)

Provider

Stanford

Rights

• Access rights: Public

Citation

Bretz, Carrie K., Kvitek, Rikk G., Cochrane, Guy R., Dartnell, Peter, Johnson, Samuel Y., Golden, Nadine E., Fugro Pelagos, Inc, Seafloor Mapping Lab, Pacific Coastal and Marine Science Center. Contours (10m): Offshore of San Gregorio, California, 2007. Geological Survey (U.S.). Line data. https://purl.stanford.edu/fh627vx6058

Format

Shapefile

Languages

• English