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H11044_GEO_WGS84_ENHAN.TIF: Enhanced composite sidescan sonar mosaic of NOAA survey H11044 in West-Central Long Island Sound off Milford, Connecticut (geographic)

Metadata also available as: OUTLINE | TEXT

Frequently-anticipated questions:

What does this data set describe?

Title:
H11044_GEO_WGS84_ENHAN.TIF: Enhanced composite sidescan sonar mosaic of NOAA survey H11044 in West-Central Long Island Sound off Milford, Connecticut (geographic)
Abstract:
The U.S. Geological Survey (USGS), 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 a section of the sea floor in west-central Long Island Sound off Milford, 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, National Oceanic and Atmospheric Administration, and Connecticut Department of Environmental Protection, 200509, H11044_GEO_WGS84_ENHAN.TIF: Enhanced composite sidescan sonar mosaic of NOAA survey H11044 in West-Central Long Island Sound off Milford, Connecticut (geographic): 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., 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.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -72.869907
    East_Bounding_Coordinate: -72.775833
    North_Bounding_Coordinate: 41.237200
    South_Bounding_Coordinate: 41.151200

  3. What does it look like?

    <http://pubs.usgs.gov/of/2005/1018/data/sidescan/h1044/enhanced/h11044_geo_wgs84_enhan-thumb.gif> (GIF)
    Thumbnail overview image of the digital sidescan sonar mosaic.
    <http://pubs.usgs.gov/of/2005/1018/data/sidescan/h1044/enhanced/h11044_geo_wgs84_enhan.gif> (GIF)
    Overview image of the digital sidescan sonar mosaic.

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

    Calendar_Date: 2004
    Currentness_Reference: ground condition

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

    Geospatial_Data_Presentation_Form: remote-sensing image

  6. How does the data set represent geographic features?

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

      This is a Raster data set. It contains the following raster data types:

      • Dimensions 30189 x 26910 x 1, type Pixel

    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 0.000001. 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 6378137.000.
      The flattening of the ellipsoid used is 1/6356752.3142451793.

  7. How does the data set describe geographic features?

    Band_1

    ObjectID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Value

    Red

    Green

    Blue

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 NOAA Ship RUDE collected the sidescan data, LTJG Marc Moser (NOAA) and Mary DiGiacomo-Cohen (CT-DEP) processed the data, Larry Poppe (USGS) created the metadata.

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

    U.S. Geological Survey
    c/o Larry Poppe
    Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    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 NOAA Survey H11044, Long Island Sound, ArcView GIS database and contains the completed 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)
    Type_of_Source_Media: CD-ROM

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

    Date: 2002 (process 1 of 3)
    The sidescan sonar imagery contained in this report was produced from data collected during 2001-2002 as part of NOAA surveys H11043 and H11044 aboard the NOAA Ship RUDE. The data for these surveys were acquired in XTF (extended Triton data format) using an Edgetech (EG&G) 272T sidescan sonar tow fish set to sweep about 100 m to either side of the ship's track. The Edgetech model 272T tow fish emits two 50°-wide beams tilted down 20° from horizontal, and transmits at 100 kHz. All side-scan sonar data were recorded digitally through a Triton Elics International ISIS data acquisition system. The sidescan sonar data were multiplexed and filtered to convert the data into the desired processing format and to remove speckle noise and corrected for slant-range distortions. and imported into SonarWeb, an application that creates mosaics from raw XTF sidescan sonar data. The mosaic include the following standards: 1 meter resolution, image 'shine through', and auto contrast adjustment (with a 12.9% contrast increase). Originally produced aboard in UTM, the image was changed to geographic

    Person who carried out this activity:

    Marc Moser
    NOAA
    Field Support Liaison
    Hydrographic Systems and Technology Program
    Norfolk, VA 23510
    USA

    Data sources used in this process:
    • XTF sidescan sonar data

    Data sources produced in this process:

    • h11044100mosaic.tif
    • h11044100mosaic.tfw

    (process 2 of 3)
    The original image was converted to ArcGIS GRID format (imagegrid command) and then reprojected from UTM zone 18 to geographic. File (originally named h11044_geo.tif) was renamed to be more descriptive and include the ellipsoid name.

    Person who carried out this activity:

    Mary DiGiacomo-Cohen
    CT-DEP
    GIS Specialist

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

    Data sources used in this process:
    • h11044100mosaic.tif (h11044_utm18_wgs84.tif)

    Data sources produced in this process:

    • h11044_geo_wgs84.tif
    • h11044_geo_wgs84.tfw

    (process 3 of 3)
    The image in ArcGIS GRID format remapped (eitest.rmp) to produce an enhance image with more contrast (customized equal interval linear spread) and a white border collar. Grid was clipped to remove excessive border resulting from projection

    Person who carried out this activity:

    Connecticut DEP
    c/o Mary DiGiacomo-Cohen
    GIS Specialist

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

    Data sources used in this process:
    • h11044_geo_wgs84.tif

    Data sources produced in this process:

    • h11044_geo_wgs84_enhan.tif
    • h11044_geo_wgs84_enhan.tfw

  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?

  2. How accurate are the geographic locations?

    Navigation was by differential GPS; postional 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?

    All collected data were processed and used to generate the digital mosaic.

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

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) and the National Oceanic and Atmospheric Administration (NOAA) as the originators of this dataset.

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

    Larry Poppe
    U.S. Geological Survey
    Geologist
    U.S. Geological Survey
    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: h11044_geo_wgs84_enhan.tif

  3. What legal disclaimers am I supposed to read?

    Although this data set has been used by the U.S. Geological Survey (USGS), Connecticut Department of Environmental Protection (CT-DEP), and the National Oceanic and Atmospheric Administration (NOAA), no warranty, expressed or implied, is made by the USGS or NOAA 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, CT-DEP, or NOAA 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.

  4. How can I download or order the data?

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

    This image is available as a GEOTIFF image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image.

Who wrote the metadata?

Dates:
Last modified: 23-Aug-2005
Metadata author:
Larry Poppe
U.S. Geological Survey
Geologist
U.S. Geological Survey
Woods Hole, MA 02543-1598
USA

(508) 548-8700 x2314 (voice)
(508) 457-2310 (FAX)
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 Wed Aug 24 12:28:09 2005