bedrock.shp: Digital polygons of bedrock outcrops on the sea floor of the Stellwagen Bank National Marine Sanctuary region.

Metadata also available as

Frequently-anticipated questions:


What does this data set describe?

Title:
bedrock.shp: Digital polygons of bedrock outcrops on the sea floor of the Stellwagen Bank National Marine Sanctuary region.
Abstract:
This data set contains the locations of exposed bedrock outcrops in the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts, an area of approximately 1100 nautical square miles. The Stellwagen Bank NMS Mapping Project is designed to provide detailed maps of the Stellwagen Bank region's environments and habitats and the first complete multibeam topographic and sea floor characterization maps of a significant region of the shallow EEZ. The bedrock outcrops were identified using multibeam topographic imagery and backscatter intensity of the seabed and video and photographic images collected from 1994 to 2003.
  1. How should this data set be cited?

    Valentine, Page C. , Scully, Lian A. , and Fuller, Sarah J. , 2005, bedrock.shp: Digital polygons of bedrock outcrops on the sea floor of the Stellwagen Bank National Marine Sanctuary region.: Scientific Investigations Map 2840, 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.

    Page C. Valentine, editor, 2005, Sea floor image maps showing topography, sun-illuminated topography, backscatter intensity, ruggedness, slope, and the distribution of boulder ridges and bedrock outcrops in the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts: Scientific Investigations Map 2840, 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: -70.599892
    East_Bounding_Coordinate: -70.176779
    North_Bounding_Coordinate: 42.779711
    South_Bounding_Coordinate: 42.587985

  3. What does it look like?

  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 (21)

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

      The map projection used is Mercator.

      Projection parameters:
      Standard_Parallel: 41.650000
      Longitude_of_Central_Meridian: -70.316700
      False_Easting: 0.000000
      False_Northing: 0.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.000064
      Ordinates (y-coordinates) are specified to the nearest 0.000064
      Planar coordinates are specified in meters

      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?

    bedrock
    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 (square meters) covered by each bedrock outcrop. (Source: USGS)

    Range of values
    Minimum:10482.241726
    Maximum:5710745.45447
    Units:square meters
    Resolution:.00001

    Perimeter
    Perimeter (meters) of each bedrock outcrop. (Source: USGS)

    Range of values
    Minimum:461.663868
    Maximum:32650.982681
    Units:meters
    Resolution:.000001

    Hectares
    Hectares covered by each bedrock outcrop. (Source: USGS)

    Range of values
    Minimum:1.048224
    Maximum:571.074545
    Units:hectares
    Resolution:.000001


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?

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

    Page C. Valentine
    U.S. Geological Survey
    Research Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    (508) 548-8700 x2239 (voice)
    (508) 457-2310 (FAX)
    pvalentine@usgs.gov


Why was the data set created?

Development of interpretive seabed maps, sea floor imagery, and a GIS database that are accessible to scientists, policymakers, managers, and the general public.


How was the data set created?

  1. From what previous works were the data drawn?

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

    (process 1 of 1)
    Bedrock outcrops were visually identified using the Stellwagen Bank sun-illuminated multibeam sonar image combined with backscatter intensity images, and where available, video and/or photographic imagery from the region and then digitized using the Editor toolbar in ArcMap.

    Data sources produced in this process:

    • bedrock.shp
    • bedrock.dbf
    • bedrock.shx

  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 observations, including topology?

    No additional checks for topological consistency were performed on the 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 from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information.

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

    Page C. Valentine
    U.S. Geological Survey
    Research Geologist
    U.S. Geological Survey
    Woods Hole, MA 02543-1598
    USA

    (508) 548-8700 x2239 (voice)
    (508) 457-2310 (FAX)
    pvalentine@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: 22-Aug-2005
Last Reviewed: 22-Aug-2005
Metadata author:
U.S. Geological Survey
c/o Page C. Valentine
Research Geologist
U.S. Geological Survey
Woods Hole, MA 02543-1598
USA

(508) 548-8700 x2239 (voice)
(508) 457-2310 (FAX)
pvalentine@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 Aug 22 09:32:31 2005