Mosaicinterp: Geologic Interpretation of the Sidescan Sonar Mosaic of NOAA survey H11045 off Bridgeport, CT

Metadata also available as OUTLINE | TEXT

Frequently-anticipated questions:

What does this data set describe?

Title:
Mosaicinterp: Geologic Interpretation of the Sidescan Sonar Mosaic of NOAA survey H11045 off Bridgeport, CT
Abstract:
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.

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 sidescan sonar mosaics (complete-coverage acoustic images of the sea floor) within specific areas of special interest (Poppe and Polloni, 1998; fig. 1). The mosaic presented herein covers a 190.3 km square area of the sea floor in west-central Long Island Sound off Bridgeport, Connecticut.

The mosaics 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 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.

  1. How should this data set be cited?

    U.S. Geological Survey, 2005, Mosaicinterp: Geologic Interpretation of the Sidescan Sonar Mosaic of NOAA survey H11045 off Bridgeport, CT: Open File Report 2005-1162, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Beaulieu, E., Poppe, L.J., Paskevich, V.F., Doran, E.F., Chauveau, B.E., Crocker, J.M., Beaver, A.L., and Schattgen, P.T., 2005, Sidescan Sonar Imagery and Surficial Geologic Interpretation of the Sea Floor off Bridgeport, Connecticut: Open-File Report 2005-1162, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

    Online Links:

    Other_Citation_Details:
    This digital publication may also be available via the web at pubs.usgs.gov

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -73.306786
    East_Bounding_Coordinate: -73.106895
    North_Bounding_Coordinate: 41.153685
    South_Bounding_Coordinate: 41.018163

  3. What does it look like?

    <http://pubs.usgs.gov/of/2005/1162/graphics/f6_interpretation.jpg> (JPEG)
    Overview showing the coverage and extent of the mosaic interpretation data layer for the H11045 NOAA sidescan sonar mosaic.

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: 2005
    Currentness_Reference: publication date

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):

      • G-polygon (19)

    2. What coordinate system is used to represent geographic features?

      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000000. Longitudes are given to the nearest 0.000000. Latitude and longitude values are specified in Decimal degrees.

      The horizontal datum used is D_WGS_1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257224.

  7. How does the data set describe geographic features?

    mosaicinterp
    Interpreted features visible on the sidescan sonar mosaic from survey H11045 (Source: USGS)

    FID
    Internal feature number. (Source: ESRI)

    Coordinates defining the features.

    Shape
    Feature geometry. (Source: ESRI)

    ID
    Number (Source: ESRI)

    MOSAICINTE
    Interpreted features visible on the sidescan sonar mosaic from survey H11045 (Source: USGS)

    Value Definition
    Pipeline Submarine pipeline
    Dredge Spoils Areas of the sea floor characterized by dumped materials
    Trawl Marks Areas of the sea floor characterized by trawl marks
    Shipwreck Shipwreck characterized by sedimentation surrounding wreck
    Sand waves Areas of the sea floor characterized by sand waves

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

    Please credit Elizabeth Beaulieu, U.S. Geological Survey, for completing the interpretation.

  3. To whom should users address questions about the data?

    U.S. Geological Survey
    c/o Larry Poppe
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543
    USA

    (508) 548-8700 x2314 (voice)
    (508) 457-2310 (FAX)
    lpoppe@usgs.gov

Why was the data set created?

This GIS overlay is a component of the Bridgeport Survey, Long Island Sound, GIS database and contains the geologic interpretion of the sidescan sonar mosaic for the study area.

How was the data set created?

  1. From what previous works were the data drawn?

    (source 1 of 1)

  2. How were the data generated, processed, and modified?

    Date: 2005 (process 1 of 1)
    The mosaic was interpreted and polygons for each type of feature were produced in ArcView as shapefiles. The shapefiles were then combined using GeoProcessing Wizard.

    Person who carried out this activity:

    U.S. Geological Survey
    c/o Lawrence J. Poppe
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543
    USA

    (508) 548-8700 x2314 (voice)
    (508) 457-2310 (FAX)
    lpoppe@usgs.gov

    Data sources used in this process:
    • h11045_geo1m_wgs84_enhn.tif

    Data sources produced in this process:

    • mosaicinterpret.shp
    • mosaicinterpret.dbf
    • mosaicinterpret.avl
    • mosaicinterp.shx

  3. What similar or related data should the user be aware of?

    (editor), V.F. Paskevich , and (editor), L.J. Poppe , 2000, Georeferenced Mapping and Bottom Photography in Long Island Sound: Open-File Report 00-304, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

    Poppe, L.J., Paskevich, V.F., Moser, M.S., DiGiacomo-Cohen, M.L., and Christman, E.B., 2004, Sidescan Sonar Imagery and Surficial Geologic Interpretation of the Sea Floor off Branford, Connecticut: Open-File Report 2004-1003, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

    Online Links:

    Other_Citation_Details:
    Data is released via CD-ROM media. This digital publication may also be available via the web at pubs.usgs.gov.
    McMullen, K.Y., Poppe, L.J., Paskevich, V.F., Doran, E.F., Moser, M.S., Christman, E.B., and Beaver, A.L., 2005, Suficial Geologic Interpretation and Sidescan Sonar Imagery of the Sea Floor off West-Central Long Island Sound: Open-File Report 2005-1018, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

    Navigation was by differential GPS, positional accuracy to less than 10 .

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Interpretations were completed on all identifiable features on the sidescan sonar masaic

  5. How consistent are the relationships among the observations, including topology?

    All polygons were constructed in a consistent manner. No additional checks for topological consistency were performed on this data.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: None
Use_Constraints:
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 dataset.

  1. Who distributes the data set? (Distributor 1 of 1)

    U.S. Geological Survey
    c/o Larry Poppe
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543
    USA

    (508) 548-8700 x2314 (voice)
    (508) 457-2310 (FAX)
    lpoppe@usgs.gov

  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

    Although this data set has been used by the U.S. Geological Survey 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.

  4. How can I download or order the data?

  5. What hardware or software do I need in order to use the data set?

    The data are available in the ESRI shapefile format. The user must have Environmental Systems Research Institute's (ESRI) ArcView 3.0 or greater or ArcGIS software to read and process the data file. In lieu of Arcview, the user may utilize another GIS application package capable of importing the data. A free GIS data viewer, ArcExplorer, is available from the ESRI website at www.esri.com/software/arcexplorer/download4.html

Who wrote the metadata?

Dates:
Last modified: 2005
Metadata author:
U.S. Geological Survey
c/o Elizabeth Beaulieu
Physical Science Lab Technician
384 Woods Hole Road
Woods Hole, MA 02543
USA

(508) 548-8700 x2277 (voice)
(508) 457-2310 (FAX)
ebeaulieu@usgs.gov

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:

Generated by mp version 2.8.6 on Mon Nov 07 10:08:41 2005