The Long Island Sound Study (LISS) compiled data from a number of different sources, integrated new data, and assembled a comprehensive spatial database for areas of the States of Connecticut, New York, and portions of Rhode Island which border Long Island Sound.

The Long Island Sound Study (LISS) compiled data from a number of different sources, integrated new data, and assembled a comprehensive spatial database for areas of the States of Connecticut, New York, and portions of Rhode Island which border Long Island Sound.

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, a major East Coast estuary surrounded by the most densely populated region of the United States. These studies have built upon cooperative research with the State of Connecticut that was initiated in 1982. The current phase of this research program is directed toward studies of sea-floor sediment distribution, processes that control sediment distribution, nearshore environmental concerns, and the relation of benthic community structures to the sea-floor geology. The bathymetry data in this data set were collected during 2001 for charting applications as part of NOAA project OPR-B340-RU, survey H11044 aboard the NOAA Ship RUDE. The RUDE, which supports NOAA's east-coast nautical charting mission, is outfitted to acquire single-beam bathymetry with an Odom Echotrac DF-3200 duel frequency echosounder and shallow water multibeam bathymetry with a Reson 8125 system. The Reson multibeam system operates at 455 KHz with a 120 degree across track swath and 240 beams along its swath.

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, a major East Coast estuary surrounded by the most densely populated region of the United States. These studies have built upon cooperative research with the State of Connecticut that was initiated in 1982. The current phase of this research program is directed toward studies of sea-floor sediment distribution, processes that control sediment distribution, nearshore environmental concerns, and the relation of benthic community structures to the sea-floor geology. The bathymetry data in this data set were collected during 2001 for charting applications as part of NOAA project OPR-B340-RU, survey H11044 aboard the NOAA Ship RUDE. The RUDE, which supports NOAA's east-coast nautical charting mission, is outfitted to acquire single-beam bathymetry with an Odom Echotrac DF-3200 duel frequency echosounder and shallow water multibeam bathymetry with a Reson 8125 system. The Reson multibeam system operates at 455 KHz with a 120 degree across track swath and 240 beams along its swath.

Digital terrain models (DTMs) produced from multibeam bathymetric data provide valuable base maps for marine geological interpretations. These maps help define the geological variability of the seafloor (one of the primary controls of benthic habitat diversity); improve our understanding of the processes that control the distribution and transport of bottom sediments, and the distribution of benthic habitats and associated infaunal community structures; and provide a detailed framework for future research, monitoring, and management activities. The bathymetric survey interpreted herein (National Oceanic and Atmospheric Administration (NOAA) survey H11255) covers roughly 95 km2 of seafloor in southeastern Long Island Sound. This bathymetry has been examined in relation to seismic reflection data collected concurrently, as well as archived seismic profiles acquired as part of a long-standing geologic mapping partnership between the State of Connecticut and the U.S. Geological Survey (USGS). The objective of this work was to use these acoustic data sets to interpret geomorphological attributes of the seafloor, and to use these interpretations to better understand the Quaternary geologic history and modern sedimentary processes.

Digital terrain models (DTMs) produced from multibeam bathymetric data provide valuable base maps for marine geological interpretations. These maps help define the geological variability of the seafloor (one of the primary controls of benthic habitat diversity); improve our understanding of the processes that control the distribution and transport of bottom sediments, and the distribution of benthic habitats and associated infaunal community structures; and provide a detailed framework for future research, monitoring, and management activities. The bathymetric survey interpreted herein (National Oceanic and Atmospheric Administration (NOAA) survey H11255) covers roughly 95 km2 of seafloor in southeastern Long Island Sound. This bathymetry has been examined in relation to seismic reflection data collected concurrently, as well as archived seismic profiles acquired as part of a long-standing geologic mapping partnership between the State of Connecticut and the U.S. Geological Survey (USGS). The objective of this work was to use these acoustic data sets to interpret geomorphological attributes of the seafloor, and to use these interpretations to better understand the Quaternary geologic history and modern sedimentary processes.

The United States Geological Survey (USGS) is working cooperatively with the National Oceanic and Atmospheric Association (NOAA) to interpret the surficial geology in estuaries along the coast of the northeastern United States. The purpose of our present study is to interpret the distributions of surficial sediments and sedimentary environments in an area of Narragansett Bay using sidescan sonar imagery, high-resolution bathymetry, and sediment data. The mosaic and bathymetry presented herein covers an area of the sea floor in central Narragansett Bay. The mosaic, bathymetry, and their interpretations serve many purposes, including: (1) defining the geological variability of the sea floor, which is one of the primary controls of benthic habitat diversity; (2) improving our understanding of the processes that control the distribution and transport of bottom sediments and the distribution of benthic habitats and associated infaunal community structures; and (3) providing a detailed framework for future research, monitoring, and management activities. The sidescan sonar mosaics and bathymetry images also serve as base maps for subsequent sedimentological, geochemical, and biological observations, because precise information on environmental setting is important for selection of sampling sites and for accurate interpretations of point measurements.

The United States Geological Survey (USGS) is working cooperatively with the National Oceanic and Atmospheric Association (NOAA) to interpret the surficial geology in estuaries along the coast of the northeastern United States. The purpose of our present study is to interpret the distributions of surficial sediments and sedimentary environments in an area of Narragansett Bay using sidescan sonar imagery, high-resolution bathymetry, and sediment data. The mosaic and bathymetry presented herein covers an area of the sea floor in central Narragansett Bay. The mosaic, bathymetry, and their interpretations serve many purposes, including: (1) defining the geological variability of the sea floor, which is one of the primary controls of benthic habitat diversity; (2) improving our understanding of the processes that control the distribution and transport of bottom sediments and the distribution of benthic habitats and associated infaunal community structures; and (3) providing a detailed framework for future research, monitoring, and management activities. The sidescan sonar mosaics and bathymetry images also serve as base maps for subsequent sedimentological, geochemical, and biological observations, because precise information on environmental setting is important for selection of sampling sites and for accurate interpretations of point measurements.

The Long Island Sound Study developed these digital data from 1:100,000-scale National Oceanic & Atmospheric Administration (NOAA) and United States Geological Survey (USGS) maps as a general reference to the depth of water in Long Island Sound. In 1996, these data were digitized from paper maps by the Long Island Sound Study (http://www.longislandsoundstudy.net) and incorporated into a Long Island Sound GIS database. Not intended for maps printed at map scales greater or more detailed than 1:100,000 scale (1 inch = 1,578 feet.) Dataset credit: Applied Geographics, Inc. of Boston, Massachussets was contracted by the Long Island Sound Study to automate and digitize these bathymetry data for Long Island Sound. Linda Bischoff, GIS Analyst, digitized the data and created the orginal metadata.

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 H11997 offshore in eastern Long Island Sound, and during May 2010 bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Two interpretive data layers were derived from the multibeam echo-sounder and the ground-truth data used to verify them. For more information on the ground-truth survey see http://quashnet.er.usgs.gov/data/2010/10015/