EarthWorks Geospatial Catalog

Backscatter A: Hueneme Canyon and Vicinity, California, 2008

Author(s)
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Description
This layer is a georeferenced raster image containing acoustic-backscatter data for Hueneme Canyon and the surrounding vicinity in California. The majority of the data for this map area was collected by CSUMB in the summers of 2006 and 2007, using a 244-kHz Reson 8101 multibeam echosounder. 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 sediment type. 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). This map was published in Scientific Investigations Map 3225. This layer is part of the 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. 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.
Publisher
Geological Survey (U.S.)
Place(s)
California, Ventura County (Calif.), and Pacific Ocean
Subject(s)
Coasts, Digital elevation models, Remote sensing, Bathymetric maps, Multibeam mapping, Submarine topography, Submarine geology, Sediments (Geology), Marine sediments, Ocean bottom, Seismic reflection method, Imagery and Base Maps, Oceans, and Elevation
Year
2006-2008
Held by
Stanford
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Use and reproduction
This item is in the public domain. There are no restrictions on use.
Copyright
This work is in the Public Domain, meaning that it is not subject to copyright.
Attribute Value
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