TEXTURE: surficial sediment distribution interpretation of the sidescan sonar mosaic of NOAA survey H11043 off Branford, Connecticut

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• 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?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
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  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

Title:

TEXTURE: surficial sediment distribution interpretation of the sidescan sonar mosaic of NOAA survey H11043 off Branford, Connecticut

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 41.1 km square area of the sea floor in north-central Long Island Sound off Branford, 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?

   Poppe, Lawrence J. , 2004, TEXTURE: surficial sediment distribution interpretation of the sidescan sonar mosaic of NOAA survey H11043 off Branford, Connecticut: U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

   Online Links:

   • <http://pubs.usgs.gov/of/2004/1003/data/interp/sedimentinterp/texture.zip>

   Other_Citation_Details: Data are released via CD-ROM media.

   This is part of the following larger work.

   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:

   • <http://pubs.usgs.gov/of/2004/1003>
   • <http://woodshole.er.usgs.gov/openfile/of2004-1003>

   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: -72.869918

   East_Bounding_Coordinate: -72.776520

   North_Bounding_Coordinate: 41.236011

   South_Bounding_Coordinate: 41.151390

3. What does it look like?

   texture (GIF)

   Overview showing the coverage and extent of the sediment texture interpretation data layer for the H11043 NOAA sidescan sonar mosaic.

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

   Calendar_Date: 2004

   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 (92)

   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?

   texture

   FID

   Internal feature number. (Source: ESRI)

   Sequential unique whole numbers that are automatically generated.

   Shape

   Feature geometry. (Source: ESRI)

   Coordinates defining the features.

   ID

   Generated number (Source: ArcView)

   Range of values
   Minimum:	0
   Maximum:	0

   SEDCLASS

   Textural classification according to Shepard (1954) (Source: Scientist)

   Value	Definition
   Gravel	Sediment grain size greater than 2 mm
   Gravelly sediment	Sediment greater than 10 percent gravel
   Sand	Sediment mostly greater than 0.062 mm, but less than 2 mm
   Silty Sand	Sand with significant (greater than 20 percent) silt
   Sand Silt Clay	Sediment with significant sand, silt, and clay
   Clayey silt	Silt with significant clay

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

2. Who also contributed to the data set?

   Lawrence J. Poppe, U.S. Geological Survey, must be referenced as the originator of the dataset in any future products or research derived from these data.

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

This GIS overlay is a component of the Branford Survey, Long Island Sound, ArcView GIS database and shows the surficial sediment distribution within the study area.

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: 31-Oct-2003 (process 1 of 1)

   The surficial sediment distribution across 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
   U.S. Geological Survey
   Woods Hole, MA 02543
   USA
   

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

   Data sources used in this process:

   • lisseddata.shp
   • h11043_geo.tif

   Data sources produced in this process:

   • texture.shp
   • texture.dbf
   • texture.avl
   • texture.shx

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

1. How well have the observations been checked?

2. How accurate are the geographic locations?

   Interpretations based on tonal changes in the osaic whose 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 of the sediment distribution across the sidescan sonar mosaic were completed using tonal changes and all available textural data.

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.

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

   508-454-8700 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 USGS, NOAA, and the State of Connecticut, no warranty, expressed or implied, is made by the USGS, NOAA, or the State of Connecticut 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, NOAA, or the State of Connecticut in the use of these data or related materials.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	Six files (texture.shp, texture.shx, texture.dbf, texture.sbn, texture.sbx, texture.avl) in format ArcView (version 3.3) ESRI shapefile Size: 0.258
     Media you can order:	CD-ROM (Density 650 Mbytes) (format ISO9660) Note: The user must have a CD-ROM capable of reading an ISO9660 standard CD-ROM

   • Cost to order the data: None

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

   Access to the data and information contained on this CD-ROM was developed using the HyperText Markup Language (HTML) utilized by the World Wide Web (WWW) project. Development of the CD-ROM documentation and user interface in HTML allows a user to access the information by using a variety of WWW information browsers to facilitate browsing and locating information and data. To access the information contained on this disk with a WWW client browser, open the file 'index.htm' at the top level directory of this CD-ROM with your selected browser.

   This CD-ROM should be readable by a variety of operating systems including Windows 95/98/NT, Macintosh and UNIX.

Dates:

Last modified: 19-Feb-2004

Metadata author:

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