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H11044SEDENV: Sedimentary Environments of NOAA H11044 Sidescan Sonar Mosaic in West-Central Long Island Sound

Metadata also available as: OUTLINE | TEXT

Frequently-anticipated questions:

What does this data set describe?

Title:
H11044SEDENV: Sedimentary Environments of NOAA H11044 Sidescan Sonar Mosaic in West-Central Long Island Sound
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. The mosaic presented herein covers almost 300 km square area of the sea floor in west-central Long Island Sound off Milford, Connecticut. The mosaics and their interpretations (represented in part by this data layer) 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, and Long Island Sound Resource Center, 2004, H11044SEDENV: Sedimentary Environments of NOAA H11044 Sidescan Sonar Mosaic in 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.

    Online Links:

    This is part of the following larger work.

    McMullen, K.Y., Poppe, L.J., Paskevich, V.F., Doran, E.F., Moser, M.S., Christman, E.B., Beaver, A.L, Christman, E.B., and Beaver, A.L., 2005, Surficial Geologic Interpretation and Sidescan Sonar Imagery of the Sea Floor in 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 02543.

    Online Links:

    Other_Citation_Details: 1 DVD-ROM

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -73.131256
    East_Bounding_Coordinate: -72.936531
    North_Bounding_Coordinate: 41.242020
    South_Bounding_Coordinate: 41.023193

  3. What does it look like?

    <http://pubs.usgs.gov/of/2005/1018/data/interp/sedenviron/h11044sedenv-thumb.gif> (GIF)
    Thumbnail image showing the interpretation of the sedimentary environment of NOAA H11044 sidescan sonar mosaic.
    <http://pubs.usgs.gov/of/2005/1018/data/interp/sedenviron/h11044sedenv.gif> (GIF)
    Overview image showing the interpretation of the sedimentary environment of NOAA H11044 sidescan sonar mosaic.

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

    Calendar_Date: 2001
    Currentness_Reference: ground condition

  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 (40)

    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?

    h11044sedenv
    Shapefile Attribute Table (Source: ESRI)

    FID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    AREA
    Area of feature in internal units squared. (Source: ESRI)

    Positive real numbers that are automatically generated.

    PERIMETER
    Perimeter of feature in internal units. (Source: ESRI)

    Positive real numbers that are automatically generated.

    H11044SED_
    ArcInfo internal feature id. Field has no applicable relevance to the data. (Source: USGS)

    H11044SED1
    ArcInfo internal feature id. Field has no applicable relevance to the data. (Source: USGS)

    SEDENVIRON
    interpretation of sidescan sonar mosaic's sedimentary environments (Source: compiler)

    ValueDefinition
    erosion or nondeposition 
    coarse-grained sediment transport 
    sorting and reworking 
    deposition 

    Character String

    Entity_and_Attribute_Overview:
    Polygons are attributed as features based on the interpretation of the sidescan sonar mosaic's sedimentary environments (erosion or nondeposition, coarse-grained transport, sorting and reworking, and deposition).

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?

    The U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), and Long Island Sound Resource Center must be acknowledged as the originators of this data set.

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

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

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

Why was the data set created?

This data layer is a component of the Milford / West-Central Survey, Long Island Sound, GIS database and represents an interpretation of the sidescan sonar mosaic for the study area. The interpretation can be used as an overlay for the mosaic image and shows the sedimentary environments of the study area such as erosion or nondeposition, coarse-grained transport, sorting and reworking, and deposition. This layer can be used in conjunction with layers: h11044seddist.shp, h11044int.shp, and images h11044_geo_wgs84_enhan.tif and h11044_geo_wgs84.tif.

How was the data set created?

  1. From what previous works were the data drawn?

    h11044_geo.tif (source 1 of 1)
    U.S. Geological Survey, National Oceanic and Atmospheric Administration, and Long Island Sound Resource Center, 2004, h11044_geo.tif.

    Type_of_Source_Media: CD-ROM
    Source_Scale_Denominator: 1 meter resolution
    Source_Contribution:
    Modified sidescan sonar mosaic (originally created by National Oceanic and Atmospheric Administration (NOAA). The sonar image was visually interpreted to create this data layer.

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

    Date: 2004 (process 1 of 2)
    The sidescan sonar imagery was interpreted to create the shapefiles representing the sedimentary environments (erosion or nondeposition, coarse-grained transport, sorting and reworking, and deposition).

    Person who carried out this activity:

    Kate McMullen
    USGS
    U.S. Geological Survey
    Woods Hole, MA 02543
    USA

    Data sources used in this process:
    • h11044_geo.tif

    Data sources produced in this process:

    • rework.shp
    • nondeposition.shp
    • deposition.shp
    • cgbt.shp

    Date: 2004 (process 2 of 2)
    The shapefiles were converted to ArcGIS coverage format, combined, edited, and cleaned (for content and consistent topology). A single study area boundary was edited and used for all associated data layers. Polygons and arcs were attributed.

    Person who carried out this activity:

    Mary DiGiacomo-Cohen
    Long Island Sound Resource Center
    Geologist / GIS Analyst
    Long Island Sound Resource Center
    Groton, CT 06340
    USA

    (860) 405-9015 (voice)
    lisrc@uconnvm.uconn.edu

    Data sources used in this process:
    • shapefiles listed in previous step

    Data sources produced in this process:

    • h11044sedenv.shp

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

    McMullen, K.Y., Poppe, L.J., DiGiacomo-Cohen, M.L., Moser, M.S., and Christman, E.B., 2005, Surficial Geology of the Sea Floor in West-Central Long Island Sound as shown by Sidescan Sonar Imagery: Northeastern Geology and Environmental Sciences v. 27, no. 1, p. 60-70, Allen Press, Lawrence, Kansas.

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

  1. How well have the observations been checked?

    Attributes have been visually checked by the compilers.

  2. How accurate are the geographic locations?

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

  3. How accurate are the heights or depths?

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

    Layer is complete as interpreted for these features.

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

    Several shapefiles representing various features identified on the mosaic were combined to create this data layer. The layers were edited and processed in a consistent manner.

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), the National Oceanic and Atmospheric Administration, and Long Island Sound Resource Center as the originators of this dataset.

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

    Lawrence J. Poppe
    U.S. Geological Survey
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    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 these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

  4. How can I download or order the data?

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

    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 the importing data. A free data viewer, arcexplorer, capable of displaying the data is available from ESRI at www.esri.com.

Who wrote the metadata?

Dates:
Last modified: 05-Aug-2005
Metadata author:
U.S. Geological Survey
c/o L.J. Poppe
Geologist
U.S. Geological Survey
Woods Hole, MA 02543
USA

(508) 548-8700 x2314 (voice)
lpoppe@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 Fri Aug 05 09:20:00 2005