Bathymetric contours were generated from soundings collected by National Ocean Service vessels from ~1900 to ~1971. The 1:250,000 maps are available for U.S. coastal waters. Bathymetric contours are in meters, with 10 meter intervals out to 200 m, supplemented by 2 m contours. Beyond 200 m, contours are at 50 m intervals to maximum depth. The GIS database derived from these maps includes the Bering, Chukchi, and Beaufort Seas in western and northern Alaska (~100 maps).

This raster dataset represents approximately 49,581 square kilometers of Simrad EM122 multibeam backscatter-intensity data collected in the Bering Sea during U.S. Geological Survey (USGS) cruise MGL1111 aboard the R/V Marcus G. Langseth. Calibrated backscatter-intensity time-series data were adjusted for range-angle, beam pattern, and power-gain distortions.

In 2010, the U.S. Geological Survey in Woods Hole, MA and St. Petersburg, FL, in partnership with the U.S. Army Corps of Engineers, Mobile District conducted geologic mapping to characterize the seafloor and shallow subsurface stratigraphy offshore of the Gulf Islands of Mississippi. The mapping was carried out during two cruises in March, 2010 on the R/V Tommy Munro of Biloxi, MS. Data were acquired with the following equipment: an SEA Ltd SwathPlus interferometric sonar (both 234 kHz and 468 kHz systems), a Klein 3000 and a Klein 3900 dual frequency sidescan-sonar, and an Edgetech 512i chirp subbottom profiling system. The long-term goal of this mapping effort is to produce high-quality, high-resolution geologic maps and geophysical interpretations that can be utilized to identify sand resources within the region and better understand the Holocene evolution and anticipate future changes in this coastal system. More information on the field work can be accessed from the Woods Hole Coastal and Marine Science Center Field Activity webpage https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-012-FA or the St. Petersburg Coastal and Marine Geology InfoBank https://walrus.wr.usgs.gov/infobank/m/m210gm/html/m-2-10-gm.meta.html.

This raster dataset represents approximately 69,060 square kilometers of Simrad EM122 multibeam-bathymetry data collected in the Gulf of Alaska during U.S. Geological Survey - Coastal and Marine Geology Program cruise MGL1109 aboard the R/V Marcus G. Langseth. The data have been reduced for position, elevation, orientation, water-column sound-speed, and refraction effects.

This raster dataset represents approximately 69,060 square kilometers of Simrad EM122 multibeam-bathymetry data collected in the Gulf of Alaska during U.S. Geological Survey - Coastal and Marine Geology Program cruise MGL1109 aboard the R/V Marcus G. Langseth. The data have been reduced for position, elevation, orientation, water-column sound-speed, and refraction effects.

This raster dataset represents approximately 69,060 square kilometers of Simrad EM122 multibeam-bathymetry data collected in the Gulf of Alaska during U.S. Geological Survey - Coastal and Marine Geology Program cruise MGL1109 aboard the R/V Marcus G. Langseth. The data have been reduced for position, elevation, orientation, water-column sound-speed, and refraction effects.

Composite 30-m resolution bathymetric surface of northern Cascadia Margin offshore Washington. The bathymetric surface is available as a GeoTIFF file.

The U.S. Geological Survey, in cooperation with the University of South Florida and Eckerd College, completed a bathymetric, sidescan sonar, high-resolution seismic-reflection, and surface sediment sampling survey of the inner shelf environment along the western Florida coast. The survey area extends 15km from Sarasota Point to Buttonwood Harbor. This study is part of a larger program initiated by the U.S. Geological Survey to map the geologic framework and monitor the modern processes that affect the western Florida coastal zone. This portion of the project included a reconnaissance high-resolution seismic and side-scan sonar surveys of the entire study area, detailed mapping to identify patterns of hard grounds and sediment cover, and coring of sediments to document historical development of the inner shelf and coastal system.

In 2002 and 2003, the U.S. Geological Survey (USGS), Woods Hole Coastal and Marine Science Center (WHCMSC), in cooperation with the National Oceanic and Atmospheric Administration (NOAA), conducted three exploration cruises (USGS Cruise 02051, NOAA RB0208, September 24 to 30, 2002; USGS Cruise 03008, NOAA RB0303, February 18 to March 7, 2003 and USGS Cruise 03032, NOAA RB0305, August 28 to September 4, 2003). These cruises mapped for the first time the morphology of this entire tectonic plate boundary stretching from the Dominican Republic in the west to the Lesser Antilles in the east, a distance of approximately 700 kilometers (430 miles). Observations from these three exploration cruises, coupled with computer modeling and published Global Positioning System (GPS) results and earthquake focal mechanisms have provided new information that is changing the evaluation of the seismic and tsunami hazard from this plate boundary. The observations collected during these cruises also contributed to the basic understanding of the mechanisms that govern plate tectonics, in this case, the creation of the island of Puerto Rico and the deep trench north of it. Results of the sea floor mapping have been an important component of the study of tsunami and earthquake hazards to the northeastern Caribbean and the U.S. Atlantic coast off the United States. For additional information on the cruises see: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2002-051-FA http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2002-051-FA http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2002-051-FA

The U.S. Geological Survey, in cooperation with the University of South Florida and Eckerd College, completed a bathymetric, sidescan sonar, high-resolution seismic-reflection, and surface sediment sampling survey of the inner shelf environment along the western Florida coast. The survey area extends 15km from Sarasota Point to Buttonwood Harbor. This study is part of a larger program initiated by the U.S. Geological Survey to map the geologic framework and monitor the modern processes that affect the western Florida coastal zone. This portion of the project included a reconnaissance high-resolution seismic and side-scan sonar surveys of the entire study area, detailed mapping to identify patterns of hard grounds and sediment cover, and coring of sediments to document historical development of the inner shelf and coastal system.