The U.S. Geological Survey (USGS), in cooperation with the Connecticut Department of Environmental Protection and National Oceanic and Atmospheric Administration (NOAA), is producing detailed geologic maps of the coastal sea floor. Imagery, originally collected by NOAA for charting purposes, provides a fundamental framework for research and management activities along this part of Long Island Sound, shows the composition and terrain of the seabed, and provides information on sediment transport and benthic habitat. Interpretive data layers were derived from the multibeam echo-sounder data and sidescan-sonar data collected north of Orient Point, New York. During April 2010, bottom photographs and surficial sediment data were acquired as part of a USGS ground-truth reconnaissance survey. For more information on the ground-truth survey see http://quashnet.er.usgs.gov/data/2010/10010/.

The U.S. Geological Survey (USGS), in cooperation with the Connecticut Department of Environmental Protection and National Oceanic and Atmospheric Administration (NOAA), is producing detailed geologic maps of the coastal sea floor. Imagery, originally collected by NOAA for charting purposes, provides a fundamental framework for research and management activities along this part of Long Island Sound, shows the composition and terrain of the seabed, and provides information on sediment transport and benthic habitat. Interpretive data layers were derived from the multibeam echo-sounder data and sidescan-sonar data collected north of Plum Island, New York. During November 2009, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey. For more information on the ground-truth survey see http://quashnet.er.usgs.gov/data/2009/09059/.

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA), is producing detailed geologic maps of the coastal sea floor. Bathymetry and sidescan-sonar imagery, originally collected by NOAA for charting purposes, provides a fundamental framework for research and management activities in Long Island Sound, shows the composition and terrain of the seabed, and provides information on sediment transport and benthic habitat. During October 2008 NOAA completed hydrographic survey H11251 offshore of Rocky Point, New York and during November 2009, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretive data layers were derived from the multibeam echo-sounder and sidescan-sonar data and the ground-truth data used to verify them. For more information on the ground-truth survey see https://cmgds.marine.usgs.gov/fan_info.php?fan=2009-059-FA

The U.S. Geological Survey, in cooperation with the National Oceanic and Atmospheric Administration and the Connecticut Department of Environmental Protection, has produced detailed geologic maps of the sea floor in Long Island Sound. These studies have built upon cooperative research with the State of Connecticut that was initiated in 1982. This research program is currently studying sea-floor sediment distribution, processes that control sediment distribution, nearshore environmental concerns, and the relation of benthic community structures to the sea-floor geology. Detailed maps of the sea floor are needed to aid in interpretation of the sea-floor geology. Therefore, sidescan-sonar data have been collected in areas of interest. Although these mosaics from NOAA surveys H11043, H11044, and H11045 in north-central Long Island Sound have been interpreted in prior reports, we have enhanced these three mosaics in order to minimize tonal artifacts created by the mismatching of backscatter in adjacent track lines. The enhanced mosaics provide a clearer image of the sea-floor geology.

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Massachusetts Office of Coastal Zone Management (MA CZM), is producing detailed geologic maps of the coastal sea floor. Sidescan-sonar imagery, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities along this part of the Massachusetts coastline, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. While acceptable for charting purposes, the original data contained numerous tonal artifacts due to environmental conditions (such as sea state), variable system settings (such as gain changes), attitude variations in the flight path of the towfish, or processing (such as lack of line to line normalization). Many of these artifacts have now been removed by enhancing the imagery to provide a more continuous grayscale GeoTIFF that enhances the true backscatter character and trends of the sea floor.

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Massachusetts Office of Coastal Zone Management (MA CZM), is producing detailed geologic maps of the coastal sea floor. Imagery, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities along this part of the Massachusetts coastline, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. Interpretive data layers were derived from multibeam echo-sounder and sidescan sonar data collected in Great Round Shoal Channel, a passage through the shoals at the eastern entrance to Nantucket Sound, off Cape Cod, Massachusetts. In June 2006, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconaissance survey.