These metadata describe acoustic-backscatter data collected during 2017 and 2018 multibeam echosounder surveys of Noyes Submarine Canyon and vicinity, southeast Alaska. Data were collected by the National Oceanic and Atmospheric Administration (NOAA) aboard the NOAA survey vessel Fairweather and the data were post-processed by the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) for PCMSC research projects. The acoustic-backscatter data are provided as a GeoTIFF image.

These metadata describe acoustic-backscatter collected during a 2015 multibeam echosounder survey near Cross Sound, southeast Alaska. Data were collected by the U.S. Geological Survey (USGS) and the Alaska Department of Fish and Game (ADFG) aboard the ADFG R/V Solstice during USGS field activity 2015-629-FA. The acoustic-backscatter data are provided as a GeoTIFF.

These metadata describe bathymetry data collected during 2017 and 2018 multibeam echosounder surveys of Noyes Submarine Canyon and vicinity, southeast Alaska. Data were collected by the National Oceanic and Atmospheric Administration (NOAA) aboard the NOAA survey vessel Fairweather and the data were post-processed by the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) for PCMSC research projects.

This part of the data release includes 10-m resolution multibeam acoustic-backscatter data collected in 2016 in Catalina Basin, southern California. The data are presented as a TIFF file. In February 2016 the University of Washington in cooperation with the U.S. Geological Survey, Pacific Coastal and Marine Science Center (USGS, PCMSC) collected multibeam bathymetry and acoustic backscatter data in Catalina Basin aboard the University of Washington's Research Vessel Thomas G. Thompson. Data were collected using a Kongsberg EM300 multibeam echosounder hull-mounted to the 274-foot R/V Thomas G. Thompson. The USGS, PCMSC processed these data and produced a series of bathymetric surfaces and acoustic-backscatter images for scientific research purposes.

This part of USGS Data Series 781 (Golden, 2019) presents 2-m-resolution acoustic backscatter data for the Offshore of Point Buchon, California, map area. Backscatter data were collected by Fugro Pelagos in 2008 using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounder systems. The data were post-processed by the California State University Monterey Bay Seafloor Mapping Lab and the University of California Santa Cruz Center for Integrated Spatial Research. The acoustic backscatter data are available as a georeferenced TIFF image. 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).

This portion of the data release presents acoustic backscatter data from the San Miguel Passage, in the Channel Islands, California. The data were collected in August 2007 by the U.S. Geological Survey, Pacific Coastal and Marine Science Center (USGS, PCMSC) using a 234.5 kHz SEA (AP) Ltd. SWATHplus-M phase-differencing sidescan sonar mounted on the NOAA, Channel Islands National Marine Sanctuary R/V Shearwater as part of the research cruise S-2-07-SC. Data were collected in water depths up to 89 meters. The San Miguel Passage is within the Channel Islands National Marine Sanctuary and is the body of water between the two western-most islands of the chain - Santa Rosa and San Miguel Islands. The data were processed at the USGS, PCMSC to create a 2-meter resolution TIFF raster, presented here.

This part of the data release contains high-resolution acoustic-backscatter data collected by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center at three study locations in the Sacramento-San Joaquin Delta, California. Data were collected in Lindsey Slough in April 2017, Middle River in March 2018, and Mokelumne River in March 2018, using an interferometric bathymetric sidescan sonar systems mounted to the USGS R/V Parke Snavely. Data are provided in 1-m resolution GeoTIFF formats. These data were collected as part of a study of the effects of invasive aquatic vegetation on sediment transport in the Sacramento-San Joaquin Delta.

Multibeam acoustic-backscatter data were collected offshore of Morro Bay, California, from 2016 to 2019. The data were collected during five separate multi-agency surveys for the U.S. Geological Survey (USGS)/Bureau of Ocean Energy Management (BOEM) California Deepwater Investigations and Groundtruthing I (Cal DIG I) project, under a collaboration with the National Oceanic and Atmospheric Administration (NOAA), using Simrad 700 series hull-mounted multibeam echosounders. Data in 2017 and 2018 were acquired by the NOAA Hydrographic Vessel Rainier (surveys H1309, H13151, and H13152). The 2018 data acquired by the Ranier were collected during USGS field activity 2018-641-FA. Additional data were collected in 2019 by the NOAA Hydrographic Survey Vessel Fairweather (survey W00479). Data from the Scripps Institution of Oceanography R/V Sally Ride collected in 2016 (survey SR1604) were used to fill in a small gap in the NOAA data. The acoustic-backscatter data from the five surveys were combined into a single raster and are provided as a 10-meter resolution GeoTIFF.

This part of USGS Data Series 781 (Golden, 2019) presents 2-m-resolution acoustic backscatter data for the Offshore of Point Estero, California, map area. Backscatter data were collected by Fugro Pelagos in 2008 using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounder systems. The data were post-processed by the California State University Monterey Bay Seafloor Mapping Lab and the University of California Santa Cruz Center for Integrated Spatial Research. The acoustic backscatter data are available as a georeferenced TIFF image. 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).

This part of USGS Data Series 781 (Golden, 2019) presents 2-m-resolution acoustic backscatter data for the Offshore of Point Estero, California, map area. Backscatter data were collected by Fugro Pelagos in 2008 using a combination of 400-kHz Reson 7125, 240-kHz Reson 8101, and 100-kHz Reson 8111 multibeam echosounder systems. The data were post-processed by the California State University Monterey Bay Seafloor Mapping Lab and the University of California Santa Cruz Center for Integrated Spatial Research. The acoustic backscatter data are available as a georeferenced TIFF image. 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).