Anthropogenic wastes, toxic chemicals, and changes in land-use patterns resulting from residential, commercial, and recreational development have stressed the environment of the Sound, causing degradation and potential loss of benthic habitats (Koppelman and others, 1976; Long Island Sound Study, 1994). Detailed maps of the sea floor are needed to help evaluate the extent of adverse impacts and to help manage resources wisely in the future. Therefore, in a continuing effort to better understand Long Island Sound, we have constructed and interpreted multibeam bathymetric data within specific areas of special interest. The outline of the composite acoustic data from surveys H11252 and H11361 in Geographic presented herein covers a roughly 156 km square area of the sea floor in the area just west of Six Mile Reef, eastern Long Island Sound. The original multibeam bathymetric data were collected during 2004 as part of charting applications aboard the NOAA Survey Vessel Thomas Jefferson. A Simrad EM1002 multibeam system mounted on the hull of this vessel was used to acquire data along survey lines from the deeper water (>20 m) parts of the study area. Two 29-foot launches with hull-mounted Reson systems were deployed from the ship and were used to acquire data along survey lines from the shallower areas.
Detailed bathymetric data 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 bathymetric data models 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 interpretation of point measurements.
U.S. Geological Survey, 2007, SMR_COMP_OUTLINE.SHP: Outline of the Composite Acoustic Data Collected During National Oceanic and Atmospheric Administration (NOAA) Surveys H11252 and H11361 (Geographic): Open-File Report 2007-1191, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.This is part of the following larger work.
Poppe, L.J., Denny, J.F., Williams, S.J., Moser, M.S., Forfinski, N.A., Stewart, H.F., and Doran, E.F., 2007, The Geology of Six Mile Reef, Eastern Long Island Sound: Open-File Report 2007-1191, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.
This is a Vector data set. It contains the following vector data types (SDTS terminology):
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees.
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is WGS84.
The semi-major axis of the ellipsoid used is 6378137.000000.
The flattening of the ellipsoid used is 1/298.257224.
Sequential unique whole numbers that are automatically generated.
Coordinates defining the features.
508-548-8700 x2314 (voice)
To release an outline of the composite multibeam bathymetric data acquired during NOAA surveys H11252 and H11361, eastern Long Island Sound, in geographic.
Person who carried out this activity:
508-548-8700 (x2314) (voice)
Data sources produced in this process:
Poppe, L.J., Williams, S.J., Moser, M.S., Forfinski, N.A., Stewart, H.F., and Doran, E.F., 2007, Quaternary geology and sedimentary processes in the vicinity of Six Mile Reef, eastern Long Island Sound: Journal of Coastal Research v. 23, no. 6.
Navigation was by differential GPS
This data layer shows the extent and locations of the areas surveyed during NOAA surveys H11252 and H11361.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Public domain data are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the originator of this information.
508-548-8700 x2314 (voice)
Although this data set has been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and/or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
|Data format:||The shapefile (smp_comp_outline.shp, smr_comp_outline.shx, smr_comp_outline.dbf) and browse graphic. in format SHP (version 3.3) ESRI polygon shapefile Size: 0.011|
|Media you can order:||DVD-ROM (Density 4.75 Gbytes) (format UDF)|
These data are available in Environmental Systems Research Institute (ESRI) shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing data. A free data viewer, ArcExplorer, capable of displaying the data is available from ESRI at www.esri.com.
508-548-8700 x2314 (voice)