MD02CHIRPLN.SHP - Tracklines for Chirp profiles collected during the 2002 MARION DUFRESNE cruise (02018) in the Gulf of Mexico

Metadata also available as - [Outline] - [Parseable text]

Frequently-anticipated questions:


What does this data set describe?

Title:
MD02CHIRPLN.SHP - Tracklines for Chirp profiles collected during the 2002 MARION DUFRESNE cruise (02018) in the Gulf of Mexico
Abstract:
Since 1982, the U.S. Geological Survey (USGS) has collected a large amount of surficial and shallow subsurface geologic information in the deep parts of the Gulf of Mexico. These data include digital sidescan sonar imagery, digital seismic-reflection data, and descriptions and analyses of piston and gravity cores. The data were collected during several different projects that addressed surficial and shallow subsurface geologic processes. Some of these data sets have already been published, but the growing interest in the occurrence and distribution of gas hydrates in the Gulf of Mexico warrants integrating these existing data and associated interpretations into a GIS to provide regional background information for ongoing and future gas hydrate research.
  1. How should this data set be cited?

    Hart, Patrick, 2005, MD02CHIRPLN.SHP - Tracklines for Chirp profiles collected during the 2002 MARION DUFRESNE cruise (02018) in the Gulf of Mexico: Open-File Report 2005-1071, 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.

    Twichell, D.C., Cross, V.A., Paskevich, V.F., Hutchinson, D.R., Winters, W.J., and Hart, P.E., 2005, GIS of selected geophysical and core data in the northern Gulf of Mexico continental slope collected by the U.S. Geological Survey: Open-File Report 2005-1071, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Science Center, Woods Hole, MA.

    Online Links:

    Other_Citation_Details: 1 DVD-ROM

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -92.268680
    East_Bounding_Coordinate: -88.894260
    North_Bounding_Coordinate: 28.292740
    South_Bounding_Coordinate: 27.167860

  3. What does it look like?

    <http://pubs.usgs.gov/of/2005/1071/data/seismic/2002/nav/md02chirpln-thumb.gif> (GIF)
    Thumbnail image showing the extent and coverage of the data layer.
    <http://pubs.usgs.gov/of/2005/1071/data/seismic/2002/nav/md02chirpln.gif> (GIF)
    Overview image showing the extent and coverage of the data layer.

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

    Beginning_Date: 01-Jul-2002
    Beginning_Time: 1812
    Ending_Date: 10-Jul-2002
    Ending_Time: 0250
    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):

      • String (41)

    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 North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

  7. How does the data set describe geographic features?

    md02chirpln
    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.

    ID
    Sequential number (Source: Software Computed)

    Range of values
    Minimum:1
    Maximum:41
    Units:integer count
    Resolution:1

    LINENUM
    Seismic line number (Source: USGS)

    Character string identifying the survey line.

    LENGTH
    Length of survey line in meters (Source: USGS)

    Range of values
    Minimum:237.737
    Maximum:31081.496
    Units:meters
    Resolution:.001

    IMAGES
    Relative path and name of image of seismic profile that is linked to this track line. (Source: USGS)

    Character string


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?

    David Twichell
    U.S. Geological Survey
    Oceanographer
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    USA

    (508) 548-8700 x2266 (voice)
    (508) 457-2310 (FAX)
    dtwichell@usgs.gov


Why was the data set created?

This GIS data layer shows the tracklines along which chirp seismic-reflection profiles were collected to aid in selecting coring sites during a cruise aboard the R/V MARION DUFRESNE in 2002. The cruise was conducted in the northern Gulf of Mexico (USGS Field Activity 02018) to recover cores for gas hydrate studies.


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 4)
    Data were received from the ship DGPS system and logged to a shipboard computer at a 5-sec interval.

    Person who carried out this activity:

    Patrick Hart
    U.S. Geological Survey
    Geophysicist
    345 Middlefield Road, MS999
    Menlo Park, CA 94025

    (650) 329-5160 (voice)
    (650) 329-5190 (FAX)
    hart@usgs.gov

    Data sources used in this process:
    • DGPS receiver

    Data sources produced in this process:

    • d-1-02-gm.060

    (process 2 of 4)
    The shipboard navigation file was edited with a field being added to include the line number for the time intervals when chirp seismic data were being collected.

    Person who carried out this activity:

    Patrick Hart
    U.S. Geological Survey
    Geophysicist
    345 Middlefield Road, MS 999
    Menlo Park, CA 94025
    USA

    650-329-5160 (voice)
    650-329-5190 (FAX)
    hart@usgs.gov

    Data sources used in this process:
    • d-1-02-gm.060

    Data sources produced in this process:

    • d-1-02-gm.063

    (process 3 of 4)
    The navigation file was edited to include only those sections along which seismic data were collected, and the resulting file was saved in ArcInfo E00 format.

    Person who carried out this activity:

    Patrick Hart
    U.S. Geological Survey
    Geophysicist
    345 Middlefield Road, MS 999
    Menlo Park, CA 94025
    USA

    650-329-5160 (voice)
    650-329-5190 (FAX)
    hart@usgs.gov

    Data sources used in this process:
    • d-1-02-gm.063

    Data sources produced in this process:

    • d-1-02-GM_NAV.E00

    (process 4 of 4)
    The ArcInfo E00 format file was opened in ArcView and saved as a shapefile.

    Person who carried out this activity:

    VeeAnn Cross
    U.S. Geological Survey
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x 2251 (voice)
    508-457-2310 (FAX)
    vatnipp@usgs.gov

    Data sources used in this process:
    • d-1-02-GM_NAV.E00

    Data sources produced in this process:

    • md02chirpln.shp

  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?

    Differential GPS navigation

  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 this data set. No duplicate features are present.


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)

    David Twichell
    U.S. Geological Survey
    Oceanographer
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    USA

    (508) 548-8700 x2266 (voice)
    (508) 457-2310 (FAX)
    dtwichell@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 (USGS), 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. 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?

    The 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 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: 12-Dec-2005
Metadata author:
David Twichell
U.S. Geological Survey
Oceanographer
384 Woods Hole Road
Woods Hole, MA 02543-1598
USA

(508) 548-8700 x2266 (voice)
(508) 457-2310 (FAX)
dtwichell@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 Dec 12 17:37:34 2005