This dataset presents the raw and processed sidescan mosaic for 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).

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.

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.

Polygon shapefile showing the coverage area of the acoustic mapping at Sandy Hook, NJ between July 2015 and August 2015. 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.

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 sidescan sonar 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.

The U.S. Geological Survey (USGS) mapped approximately 336 square kilometers of the lower shoreface and inner-continental shelf offshore of Fire Island, New York in 2011 using interferometric sonar and high-resolution chirp seismic-reflection systems. These spatial data support research on the Quaternary evolution of the Fire Island coastal system and provide baseline information for research on coastal processes along southern Long Island. For more information about the WHCMSC Field Activity, see https://cmgds.marine.usgs.gov/fan_info.php?fan=2011-005-FA.

Multibeam sonar data collected with an EchoBoat 160 (Seafloor Systems inc.), an autonomous surface vessel (ASV), equipped with an iWBMSe mutibeam sonar (Norbit). Data collected and processed by NPS WRD OCRP staff.

This dataset contains bathymetry data collected during 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).

In August of 2013, the U.S. Geological Survey (USGS) conducted geophysical surveys offshore of Petit Bois Island, Mississippi. These efforts are a continued part of the U.S. Geological Survey Gulf of Mexico Science Coordination partnership with the U.S. Army Corps of Engineers (USACE) to assist the Mississippi Coastal Improvements Program (MsCIP) and the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazards Susceptibility Project, by mapping the shallow geologic stratigraphic framework of the Mississippi Barrier Island Complex. These geophysical surveys will provide the data necessary for scientists to define, interpret, and provide baseline bathymetry and seafloor habitat for this area to aid scientists in predicting future geomorphological changes to the islands with respect to climate change, storm impacts, and sea level rise. Furthermore, these data combined with the geomorphological results will provide the properties and extent of local offshore sand sediment resources available for planning and execution of the Gulf Islands National Seashore barrier island restoration. The geophysical data were collected during one cruise (USGS Field Activity Numbers 13CCT04) aboard the University of Southern Mississippi Research Vessel Tommy Munro offshore along the gulf side of Petit Bois Island, Gulf Islands National Seashore, Mississippi. Data were acquired with the following equipment: a Systems Engineering and Assessment, Ltd., SWATHplus interferometric sonar (468 kilohertz (kHz)), an EdgeTech 424 (4-24 kHz), an EdgeTech 525i chirp sub-bottom profiling system, and a Klein 3900 sidescan sonar system. This report serves as an archive of the processed interferometric swath bathymetry and sidescan sonar data. Geographic information system data products include an interpolated digital elevation model, an acoustic backscatter mosaic, a trackline map, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata. NOTE: These data are scientific in nature and are not to be used for navigation. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Government.