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. Bathymetric and sidescan-sonar data, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities along this part of Block Island Sound, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. During June 2012, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretations were derived from the multibeam-echosounder, sidescan-sonar, sedimentary, and photographic data collected in Block Island Sound. For more information on the ground-truth survey see .

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. Bathymetric and sidescan-sonar data, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities along this part of Block Island Sound, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. During June 2012, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretations were derived from the multibeam-echosounder, sidescan-sonar, sedimentary, and photographic data collected in Block Island Sound. For more information on the ground-truth survey see .

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. Bathymetric and sidescan-sonar data, originally collected by NOAA for charting purposes, provide a framework for research and management activities along western Block Island Sound, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. During June 2013, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretations were derived from the multibeam-echosounder, sidescan-sonar, sedimentary, and photographic data collected in Block Island Sound. For more information on the ground-truth survey see https://cmgds.marine.usgs.gov/fan_info.php?fan=2013-005-FA.

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. Bathymetric data, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities along this part of Block Island Sound, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. During June 2013, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretations were derived from the multibeam-echosounder, sedimentary, and photographic data collected in Block Island Sound. For more information on the ground-truth survey see https://cmgds.marine.usgs.gov/fan_info.php?fan=2013-005-FA.

The USGS, in cooperation with NOAA, is producing detailed maps of the seafloor off southern New England. The current phase of this cooperative research program is directed toward analyzing how bathymetric relief relates to the distribution of sedimentary environments and benthic communities. As part of this program, digital terrain models (DTMs) from bathymetry collected as part of NOAA's hydrographic charting activities are converted into ESRI raster grids and imagery, verified with bottom sampling and photography, and used to produce interpretations of seabed geology and hydrodynamic processes. Although each of the 7 continuous-coverage, completed surveys individually provides important benthic environmental information, many applications require a geographically broader perspective. For example, the usefulness of individual surveys is limited for the planning and construction of cross-Sound infrastructure, such as cables and pipelines, or for the testing of regional circulation models. To address this need, we integrated the 7 contiguous multibeam bathymetric DTMs into one dataset that covers much of Block Island Sound. The new dataset is adjusted to mean lower low water, is provided in UTM Zone 19 NAD83 and geographic WGS84 projections, and is gridded to 4-m resolution. This resolution is adequate for seafloor-feature and process interpretation, but small enough to be queried and manipulated with standard GIS programs and to allow for future growth. Natural features visible in the grid include boulder lag deposits of submerged moraines, sand-wave fields, and scour depressions that reflect the strength of the oscillating tidal currents. Bedform asymmetry allows interpretations of net sediment transport. Together the merged data reveal a larger, more continuous perspective of bathymetric topography than previously available, providing a fundamental framework for research and resource management activities off this portion of the Rhode Island coast. Interpretations were derived from the multibeam echo-sounder data and the ground-truth data used to verify them. For more information on the ground-truth surveys see http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2011-006-FA

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. Bathymetric data, originally collected by NOAA for charting purposes, provide a framework for research and management activities along southern Narragansett Bay, show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. During September 2014, bottom photographs and surficial sediment data were acquired as part of a ground-truth reconnaissance survey of this area. Interpretations were derived from the multibeam-echosounder, sedimentary, and photographic data collected in Narragansett Bay. For more information on the ground-truth survey see https://cmgds.marine.usgs.gov/fan_info.php?fan=2014-046-FA.

Many scientific questions and policy issues related to sediments in Long Island Sound require data of historical, regional and interdisciplinary scope. Existent data is often geographically clustered and its references are widely dispersed and not always accessible. Acquisition of new data is expensive and may duplicate previous efforts if a full interpretation of existent data has not occurred. Consequently, the body of existing data needs to be utilized to its maximum so that it can serve as a foundation, baseline, and starting point for further work. An accessible, documented, and simple-to-use compilation of existing data on sediment properties is essential for environmental managers, policy-makers, scientific researchers, and interested members of the public. To this end, we have compiled, edited, and integrated all of the available data on sediment texture and bottom descriptions throughout the Sound in order to produce a regional dataset which will be available to a wide variety of current and potential users. The significant feature of this textural dataset is that it comprehensively contains original data from many heterogeneous sources.

Many scientific questions and policy issues related to sediments in Long Island Sound require data of historical, regional and interdisciplinary scope. Existent data is often geographically clustered and its references are widely dispersed and not always accessible. Acquisition of new data is expensive and may duplicate previous efforts if a full interpretation of existent data has not occurred. Consequently, the body of existing data needs to be utilized to its maximum so that it can serve as a foundation, baseline, and starting point for further work. An accessible, documented, and simple-to-use compilation of existing data on sediment properties is essential for environmental managers, policy-makers, scientific researchers, and interested members of the public. To this end, we have compiled, edited, and integrated all of the available data on sediment texture and bottom descriptions throughout the Sound in order to produce a regional dataset which will be available to a wide variety of current and potential users. The significant feature of this textural dataset is that it comprehensively contains original data from many heterogeneous sources.