In spring and summer 2017, the U.S. Geological Survey’s Gas Hydrates Project conducted two cruises aboard the research vessel Hugh R. Sharp to explore the geology, chemistry, ecology, physics, and oceanography of sea-floor methane seeps and water column gas plumes on the northern U.S. Atlantic margin between the Baltimore and Keller Canyons. Split-beam and multibeam echo sounders and a chirp subbottom profiler were deployed during the cruises to map water column backscatter, sea-floor bathymetry and backscatter, and subsurface stratigraphy associated with known and undiscovered sea-floor methane seeps. The first cruise, known as the Interagency Mission for Methane Research on Seafloor Seeps and designated as field activity 2017-001-FA, was conducted from May 4 to May 11, 2017, and acquired geophysical data to support remotely operated vehicle exploration of seep sites using the Global Explorer, which is operated by Oceaneering International, Inc. Geophysical operations during cruise 2017-002-FA from August 25 to September 6, 2017, were also focused on mapping water column methane plumes, sea-floor seep sites, and subseafloor strata, but primarily supported conductivity, temperature, and depth instrument deployment, surface-water methane-concentration mapping, and water-sampling operations as part of a collaborative study with the University of Rochester of the effect of methane seepage on ocean water biogeochemistry. The National Oceanic and Atmospheric Administration’s Office of Ocean Exploration and Research partially sponsored cruise 2017-001-FA, and the U.S. Department of Energy partially sponsored both cruises.

In spring and summer 2017, the U.S. Geological Survey’s Gas Hydrates Project conducted two cruises aboard the research vessel Hugh R. Sharp to explore the geology, chemistry, ecology, physics, and oceanography of sea-floor methane seeps and water column gas plumes on the northern U.S. Atlantic margin between the Baltimore and Keller Canyons. Split-beam and multibeam echo sounders and a chirp subbottom profiler were deployed during the cruises to map water column backscatter, sea-floor bathymetry and backscatter, and subsurface stratigraphy associated with known and undiscovered sea-floor methane seeps. The first cruise, known as the Interagency Mission for Methane Research on Seafloor Seeps and designated as field activity 2017-001-FA, was conducted from May 4 to May 11, 2017, and acquired geophysical data to support remotely operated vehicle exploration of seep sites using the Global Explorer, which is operated by Oceaneering International, Inc. Geophysical operations during cruise 2017-002-FA from August 25 to September 6, 2017, were also focused on mapping water column methane plumes, sea-floor seep sites, and subseafloor strata, but primarily supported conductivity, temperature, and depth instrument deployment, surface-water methane-concentration mapping, and water-sampling operations as part of a collaborative study with the University of Rochester of the effect of methane seepage on ocean water biogeochemistry. The National Oceanic and Atmospheric Administration’s Office of Ocean Exploration and Research partially sponsored cruise 2017-001-FA, and the U.S. Department of Energy partially sponsored both cruises.

The U.S. Geological Survey (USGS) Woods Hole Coastal and Marine Science Center (WHCMSC) completed a bathymetric and shallow seismic-reflection survey during the period of June 9, 2021 to June 24, 2021 in water depths from 2 m to 30 m for a portion of the outer Cape Cod nearshore environment between Marconi and Nauset Beaches. The products from this survey will help to support white shark research on their shallow-water behavior in the dynamic nearshore environment at Cape Cod National Seashore (CACO). CACO visitors’ safety is threatened by interactions between the public and white sharks. This project provides CACO with baseline data and information on nearshore white shark habitat, specifically in the nearshore shoreface, bathymetric trough, and longshore bar. This data release provides the geophysical data collected from outer Cape Cod during USGS Field Activities 2021-002-FA in 2021.

ArcInfo GRID format bathymetry data generated from the 2001 multibeam sonar survey the major deltas of southern Puget Sound, WA., including Nisqually, Puyallup, and Duwamish Deltas. This is meatadata for the Nisqually Delta multibeam bathymetry data.

ArcInfo GRID format bathymetry data generated from the 2001 multibeam sonar survey the major deltas of southern Puget Sound (Tacoma), WA., including Nisqually, Puyallup, and Duwamish Deltas. This is metadata for the Puyallup Delta multibeam bathymetry data.

Processed Reson 7111 multibeam line files from a May 2015 survey offshore Cross Sound, southeast Alaska. Data were collected and processed by the U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center (PCMSC) with fieldwork activity number 2015-629-FA. Data are provided as generic sensor format (GSF) line files.

In November 2021, the U.S. Geological Survey collected high-resolution multibeam sonar data in the vicinity of Eel Pond, in Woods Hole, Massachusetts using a dual-head Teledyne Seabat T20-R multibeam echo sounder (MBES). The main objective of this survey was to evaluate new sonar system features prior to their use in future field activities. In addition to bathymetry and relative acoustic backscatter data, normalized acoustic backscatter data were also collected. Unlike relative backscatter data, normalized backscatter data compensate for adjustments made to sonar power, gain, absorption, spreading, and frequency parameters made during acquisition. In order for backscatter intensity levels to remain consistent along survey lines, and from line to line, relative backscatter data require that minimal adjustments are made to these parameters during acquisition, which can degrade the sonar performance for a given survey site. However, the ability to allow the sonar acquisition software to change sonar parameters based on variations in bathymetry and the survey environment during acquisition allows these parameters to be optimized. Having these parameters optimized for this survey allowed the USGS to evaluate this new normalized backscatter capability to ensure the collected backscatter intensity levels were referenced to a factory calibrated level. Eel Pond in Woods Hole, MA was chosen as a test area for its proximity to the USGS Coastal and Marine Science Center. It provides a variety of substrates on which to evaluate the performance of the sonar, and bathymetric/backscatter data of this area may prove useful to other projects and institutions in the area.

In June 2022, the U.S. Geological Survey, in collaboration with the Massachusetts Office of Coastal Zone Management, collected high-resolution geophysical data, in Nantucket Sound to understand the regional geology in the vicinity of Horseshoe Shoal. This effort is part of a long-term collaboration between the USGS and the Commonwealth of Massachusetts to map the State’s waters, support research on the Quaternary evolution of coastal Massachusetts, resolve the influence of sea-level change and sediment supply on coastal evolution, and strengthen efforts to understand the type, distribution, and quality of subtidal marine habitats. This collaboration produces high-resolution geologic data that serve the needs of research, management, and the public. Data collected as part of this mapping cooperative continue to be released in a series of USGS Open-File Reports and Data Releases https://www.usgs.gov/centers/whcmsc/science/geologic-mapping-massachusetts-seafloor.

High resolution bathymetric, sea-floor backscatter, and seismic-reflection data were collected offshore of southeastern Louisiana aboard the research vessel Point Sur on May 19-26, 2017, in an effort to characterize mudflow hazards on the Mississippi River Delta front. As the initial field program of a research cooperative between the U.S. Geological Survey, the Bureau of Ocean Energy Management, and other Federal and academic partners, the primary objective of this cruise was to assess the suitability of sea-floor mapping and shallow subsurface imaging tools in the challenging environmental conditions found across delta fronts (for example, variably distributed water column stratification and widespread biogenic gas in the shallow subsurface). Approximately 675 kilometers (km) of multibeam bathymetry and backscatter data, 420 km of towed chirp data, and 550 km of multichannel seismic data were collected. Varied mudflow (gully, lobe), prodelta morphologies, and structural features were imaged in selected survey areas from Pass a Loutre to Southwest Pass.