This dataset shows the cruise tracklines for the acoustic survey completed to the east of the new breachway created by Hurricane Sandy in 2012. The data was collected June 11th-16th, 2015.

Conductivity, Temperature, and Depth (CTD) Profiles associated with submerged mapping cruises, FIIS

This dataset shows the NPS park boundary for FIIS within Moriches Bay. The boundary was manually delineated from the boundary illustrated on NOAA chart 12352.

This dataset shows 2 m depth contours within the study area.

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.

Surveys of the bathymetry and backscatter intensity of the sea floor south of Long Island, New York, were carried out in November 1998 using a Simrad EM1000 multibeam echosounder mounted on the Canadian Coast Guard ship Frederick G. Creed. The purpose of the multibeam echosounder surveys was to explore the bathymetry and backscatter intensity of the sea floor in several areas off the southern coast of Long Island along the 20-meter isobath. Survey areas offshore of Fire Island Inlet, Moriches Inlet, Shinnecock Inlet, and southwest of Montauk Point were about 1 kilometer (km) wide and 10 km long. The area was mapped by the U.S. Geological Survey with support from the Canadian Hydrographic Service and the University of New Brunswick.

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.

Sediment Grain Size and CMECS Classification Data used to construct benthic habitat maps for FIIS. The ground-truth surveys involved the collection of surficial grab samples of the seafloor, sediment profile imagery (SPI), and underwater video. The three instruments were deployed together, allowing for co-located datasets. Combined, these datasets help provide a thorough understanding of the study areas, as they capture sediment and biological community characteristics at various spatial scales and resolutions.

This dataset presents the processed sidescan mosaic for Fire Island National Seashore. 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. 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 data. 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). All of the acoustic data were examined manually to confirm quality and accuracy. For sidescan, processing followed standard techniques of bottom-tracking the data and then applying angle-varying gains (AVG) and look-up tables (LUT) as necessary to correct for water column returns, arrival angle, and contrast to produce color-balanced sidescan sonar images. The native images are displayed as an inverse gold color scale, with pixel values ranging from zero (dark gold) to 255 (white). The lighter pixels indicate hard acoustic returns and represent the presence of hard surficial sediments (e.g. coarse sand, cobbles, and boulders), whereas darker pixels represent the presence of soft sediments, which tend to absorb sound to a greater degree. The horizontal coordinate system was set to UTM Zone 18N and sidescan data was processed to 25cm pixel resolution.

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. This report presents maps of bathymetry, acoustic backscatter, the coastal plain unconformity, the Holocene marine transgressive surface and modern sediment thickness. 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. More information about this field activity and the data collected can be found at the Field Activity Web Page (http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2011-005-FA)