The side scan sonar survey was done simultaneously with the bathymetry swath survey and used an EdgeTech Model 4125 Towfish bow-mounted from Lookdown at 400 and 900 kHz. The 4125 Towfish utilizes EdgeTech’s Full Spectrum CHIRP technology to produce higher resolution images than a non-CHIRP system. EdgeTech Discovery Software was used to acquire the side scan sonar data using the JSF format at a resolution of about 2.3 cm. All JSF files collected using EdgeTech’s Discover Software were processed using John Gann’s Chesapeake Technology SonarWiz5. Dimensions of contacts should be considered accurate to +/- 30% of the measured dimensions. This system also records the direct arrival intensity data.

This dataset shows the extent of bathymetry data collected during acoustic surveys completed within and adjacent to the boundaries of Cape Cod National Seashore (CACO) from 2014-2015. Full coverage sidescan and partial coverage bathymetry data were collected using an Edgetech 6205 Phase-Measuring Sidescan Sonar. In total, 668 hectares were mapped at primarily 20 – 40 meter line spacing and 50 meter swath range to allow overlap of lines.

This dataset shows the bathymetry data collected during acoustic surveys completed within and adjacent to the boundaries of Cape Cod National Seashore (CACO) from 2014-2015. Full coverage sidescan and partial coverage bathymetry data were collected using an Edgetech 6205 Phase-Measuring Sidescan Sonar. In total, 668 hectares were mapped at primarily 20 – 40 meter line spacing and 50 meter swath range to allow overlap of lines.

These data present the processed bathymetry mosaic for FIIS. The bathymetry data was collected June 11th-16th, 2015. The acoustic sonar survey was conducted using a EdgeTech 6205, a Multi-Phase Echo sounder system. This combined bathymetry and dual-frequency sidescan sonar system is optimized for shallow water surveying and is capable of acquiring bathymetry swath widths up to 8x the water depth. The sonar system was bow-mounted to a 28-ft pontoon survey vessel customized for shallow water surveying, including having a draft of less than one foot. Data was collected using GeoDas software developed by Ocean Imaging Consultants (OIC) and monitored topside in real-time to ensure quality of data and full-coverage sidescan was being achieved. The data were collected in association with an Applanix POS MV system to assure positional accuracy and to correct for vessel motion (pitch, roll, heave). The survey was designed to acquire full-coverage sidescan data and partial coverage bathymetry. As such, the survey was composed of parallel track lines with line spacing of 35 to 50 m and a sonar swath range of 50 m (25 m per side) to ensure overlap with adjacent lines. The raw sidescan and bathymetry records were processed using OIC CleanSweep software (Version 3.8.0, Build #263). For bathymetry, the processing following standard techniques of first correcting for tide, sound velocity, and vessel motion. Filters were then applied to remove outlier soundings. The resulting mosaic presents water depths of the survey area. All of the acoustic data were examined manually to confirm quality and accuracy. The horizontal coordinate system was set to UTM Zone 18N and bathymetry data was processed to 50cm pixel resolution.

Mapping extent of acoustic surveys completed along the 58‐km long Assateague barrier island stretching from the Ocean City inlet in Maryland, down past Chincoteague Island in northern Virginia. The data was collected June 20th-25th, 2014 and May 12th - 21th, 2015. Full coverage side-scan sonar and partial coverage bathymetry data were collected using an EdgeTech 6205 Multiphase Echosounder. In total, 73 square kilometers were mapped at primarily at 100m line spacing and 80 m swath range per channel (to allow overlap between lines).

The United States Geological Survey Saint Petersburg Coastal and Marine Science Center (USGS SPCMSC), in cooperation with the United States Army Corps of Engineers (USACE) conducted bathymetric surveys of the nearshore waters surrounding Ship and Horn Islands, Gulf Islands National Seashore, Mississippi (GUIS). Camille Cut separates Ship Island into East Ship Island and West Ship Island. The objective of this study was to establish base-level elevation conditions around West Ship Island, East Ship Island, Horn Island and their associated active littoral system prior to restoration activities. These activities include the closure of Camille Cut and the placement of sediment in the littoral zone of West Ship Island. This survey will be used to verify sediment migration patterns by monitoring elevation change over time. The dataset produced by this survey will also be compared with historic bathymetric datasets to help further understand island elevation over time. This data release provides 667-line kilometers (km) of processed Single-Beam Bathymetry (SBB) data and 773-line km of processed Interferometric Bathymetry (IFB) collected by the USGS SPCMSC in July 2016 (field activity number [FAN] 2016-347-FA). The IFB data were acquired aboard the Research Vessel (RV) Sallenger (subFAN, 16BIM04), and the SBB data were acquired aboard the RV Jabba Jaw (subFAN, 16BIM05) and the RV Mako (subFAN, 16BIM06). The IFB and SBB point data are provided in three datums: 1) the International Terrestrial Reference Frame of 2000 (ITRF00), ellipsoid height (-49.70 meters [m] to -28.87 m); 2) the North American Datum of 1983 (NAD83) CORS96 realization and the North American Vertical Datum 1988 (NAVD88) with respect to the GEOID12B model (-0.07 m to -20.69 m); and 3) NAD83 (CORS96) and Mean Lower Low Water (MLLW) (-0.04 m to -20.60 m). This metadata record describes the comprehensive, 50-meter (m) Digital Elevation Model (DEM) created from the IFB and SBB point data and provided in NAD83 NAVD88 GEOID12B. For additional information regarding data collection and processing, please refer to the field logs and formal Federal Geographic Data Committee (FGDC) metadata for the individual XYZ point data files and survey trackline shapefiles also included within this data release (https://doi.org/10.5066/F7B8571Q).

During the summers of 2008 and 2009 the United States Geological Survey (USGS) conducted bathymetric surveys from West Ship Island, Mississippi, to Dauphin Island, Alabama, as part of the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazard Susceptibility project. The survey area extended from the shoreline out to approximately two kilometers and included the adjacent passes. These findings were originally published in Dewitt and others (2012). This USGS data release includes updated elevation point data (xyz) in which NOAA's Vdatum version 3.6 was used convert the 2008-2009 XYZ soundings to Universal Transverse Mercator (UTM) North American Datum of 1983 (NAD83) horizontal datum and North American Vertical Datum of 1988 (NAVD88) GEOID12B vertical datum. One goal of this work was to create time-series of bathymetric change maps around the islands using data collected between 1916 to 1920, 2008 to 2009, and in 2016.

The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC), collected single beam and swath bathymetry data from the northern Chandeleur Islands, Louisiana, in June of 2016. This USGS data release includes the resulting processed elevation point data (xyz) and an interpolated digital elevation model (DEM). This USGS data release provides 229-line kilometers (km) of processed single beam bathymetry (SBB) data collected under Field Activity Number (FAN) 2016-335-FA. This FAN encompasses two subfans each of which represents one survey vessel; the RV Sallenger (subfan 16BIM01) and the RV Jabba Jaw (subFAN 16BIM02). SBB and IFB point data (x,y,z) are provided in two datums; the International Terrestrial Reference Frame of 2008 (ITRF08) and ellipsoid height and the North American Datum of 1983 (NAD83) in the CORS96 realization for the horizontal and the North American Vertical Datum of 1988 (NAVD88) GEOID09, orthometric height for the vertical. Additional files provided in this data release include: trackline shapefiles, digital and handwritten field logs, and a comprehensive 50-meter Digital Elevation Model (DEM).

The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC), collected single beam and swath bathymetry data from the northern Chandeleur Islands, Louisiana, in June of 2016. This USGS data release includes the resulting processed elevation point data (xyz) and an interpolated digital elevation model (DEM). This USGS data release provides 208-line kilometers (km) of processed interferometric bathymetry (IFB) data collected under Field Activity Number (FAN) 2016-335-FA. This FAN encompasses two subfans each of which represents one survey vessel; the research vessel (RV) Sallenger (subFAN 16BIM01) collected IFB data and the RV Jabba Jaw (subFAN 16BIM02) acquired single beam bathymetry (SBB) data. SBB and IFB point data (xyz) are provided in two datums; the International Terrestrial Reference Frame of 2008 (ITRF08) and ellipsoid height and the North American Datum of 1983 (NAD83) in the CORS96 realization for the horizontal and the North American Vertical Datum of 1988 (NAVD88) GEOID09, orthometric height for the vertical. Additional files provided in this data release include: trackline shapefiles, digital and handwritten field logs, and a comprehensive 50-meter DEM. For further information regarding IFB data collection and/or processing methods from 2011 and 2012, refer to USGS Data Series 847 and 848(https://doi.org/10.3133/ds847 and https://doi.org/10.3133/ds848).

This part of USGS Data Series 935 (Cochrane, 2014) presents bathymetry and topography data for the Offshore of Seattle, California, map area, a part of the Southern Salish Sea Habitat Map Series. The data for this map area are a combination of topography extracted from a pre-existing Digital Elevation Model (DEM) merged with bathymetry data that were collected by the National Oceanic and Atmospheric Administration (NOAA) using multibeam sonar systems. The merged data are available for download in a single zip file (BathyTopo_OffshoreSeattle.zip).