2010-012-FA_SeismicTrackline.shp - Survey lines along which EdgeTech SB-512i chirp seismic-reflection data were collected by the U.S. Geological Survey - Woods Hole Coastal and Marine Science Center offshore of the Gulf Islands, MS, 2010 (ESRI polyline shapefile)

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

Frequently-anticipated questions:

What does this data set describe?

Title:
2010-012-FA_SeismicTrackline.shp - Survey lines along which EdgeTech SB-512i chirp seismic-reflection data were collected by the U.S. Geological Survey - Woods Hole Coastal and Marine Science Center offshore of the Gulf Islands, MS, 2010 (ESRI polyline shapefile)
Abstract:
In 2010, the U.S. Geological Survey in Woods Hole, MA and St. Petersburg, FL, in partnership with the U.S. Army Corps of Engineers, Mobile District conducted geologic mapping to characterize the seafloor and shallow subsurface stratigraphy offshore of the Gulf Islands of Mississippi. The mapping was carried out during two cruises in March, 2010 on the R/V Tommy Munro of Biloxi, MS. Data were acquired with the following equipment: an SEA Ltd SwathPlus interferometric sonar (both 234 kHz and 468 kHz systems), a Klein 3000 and a Klein 3900 dual frequency sidescan-sonar, and an Edgetech 512i chirp subbottom profiling system. The long-term goal of this mapping effort is to produce high-quality, high-resolution geologic maps and geophysical interpretations that can be utilized to identify sand resources within the region and better understand the Holocene evolution and anticipate future changes in this coastal system. More information on the field work can be accessed from the Woods Hole Coastal and Marine Science Center Field Activity webpage <http://quashnet.er.usgs.gov/data/2010/10012/> or the St. Petersburg Coastal and Marine Geology InfoBank <http://walrus.wr.usgs.gov/infobank/m/m210gm/html/m-2-10-gm.meta.html>.
  1. How should this data set be cited?

    U.S. Geological Survey, 2011, 2010-012-FA_SeismicTrackline.shp - Survey lines along which EdgeTech SB-512i chirp seismic-reflection data were collected by the U.S. Geological Survey - Woods Hole Coastal and Marine Science Center offshore of the Gulf Islands, MS, 2010 (ESRI polyline shapefile): Open-File Report 2010-1178, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Pendleton, Elizabeth A. , Baldwin, Wayne E. , Danforth, William W. , Dewitt, Nancy T. , Forde, Arnell S. , Foster, David S. , Kelso, Kyle W. , Pfeiffer, William R. , Turecek, Aaron M. , Flocks, James G. , and Twichell, David C. , 2011, Geophysical Data from offshore of the Gulf Islands National Seashore, Cat Island to Western Horn Island, Mississippi: Open-File Report 2010-1178, U.S. Geological Survey, Coastal and Marine Geology Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -89.082139
    East_Bounding_Coordinate: -88.710194
    North_Bounding_Coordinate: 30.229300
    South_Bounding_Coordinate: 30.092922

  3. What does it look like?

    <https://pubs.usgs.gov/of/2010/1178/GIS_catalog/Tracklines/2010-012-FA_seistrks.png> (PNG)
    Woods Hole Coastal and Marine Science Center EdgeTech SB-512i trackline navigation offshore of the Gulf Islands, MS

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

    Beginning_Date: 04-Mar-2010
    Ending_Date: 17-Mar-2010
    Currentness_Reference:
    Data were not collected on 20100310, and 20100312-20100314 due to weather conditions, crew changes, or survey location.

  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 (240)

    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 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?

    2010-012-FA_SeismicTrackline
    Trackline for seismic profiles (Source: USGS)

    FID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    FileName
    Name of seismic data file (Source: USGS)

    Sequential line and file numbers used to distinguish tracklines

    ImageName
    Name of seismic profile PNG image used as hyperlink (Source: USGS)

    Sequential line and file numbers used to distinguish tracklines

    Shot
    Initial shot number in the profile (Source: USGS)

    Range of values
    Minimum:1
    Maximum:1
    Units:shot number
    Resolution:1

    Year
    Calendar year data were collected (Source: USGS)

    ValueDefinition
    2010year

    JulDay
    Julian day data were collected (Julian day is the integer number representing the interval of time in days since January 1 of the year) (Source: USGS)

    Range of values
    Minimum:63
    Maximum:76
    Units:day

    Shot_end
    Final shot number in the profile (Source: USGS)

    Range of values
    Minimum:174
    Maximum:12478
    Units:shot number
    Resolution:1

    Length
    Length of profile in kilometers (UTM Zone 16N, WGS84) (Source: USGS)

    Range of values
    Minimum:0.21
    Maximum:13.33
    Units:kilometer

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 C. Twichell
    U.S. Geological Survey
    Oceanographer
    384 Woods Hole Rd.
    Woods Hole, MA 02543-1598

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

Why was the data set created?

This dataset contains trackline navigation for approximately 1523 km of EdgeTech SB-512i chirp seismic-reflection data collected by the U.S. Geological Survey - Woods Hole Coastal and Marine Science Center in 2010. The seismic-reflection data are used to define sub-surface stratigraphy offshore of the Gulf Islands in Mississippi, and these navigation data can help spatially correlate the seismic-reflection profiles with other data in the GIS.

How was the data set created?

  1. From what previous works were the data drawn?

    (source 1 of 1)
    Type_of_Source_Media: disc
    Source_Contribution:
    High-resolution chirp seismic-reflection profiles were collected using an EdgeTech Geo-Star Full Spectrum Sub-bottom (FSSB) system and SB-512i towfish (0.5-12 kHz) (EdgeTech, 2008). SonarWiz.MAP +SBP acquisition software (Chesapeake Technology Inc., 2009) was used to control the Geo-Star topside unit and digitally log trace data in the Society of Exploration Geophysicists Y (SEG-Y), revision 1, standard format (Norris and Faichney, 2002). The SB-512i towfish was mounted on a catamaran and towed astern of the starboard side of the vessel. Navigation coordinates (in arc-seconds) were obtained from a DGPS antenna mounted on the catamaran and logged to the SEG-Y trace headers. Data were acquired using a 0.5 to 8 kHz frequency sweep, a 5 millisecond pulse length, a 0.25 second shot rate, a 46 microsecond sample interval, and a 100 millisecond record length. A total of 1523 km of seismic data were collected.

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

    Date: Mar-2010 (process 1 of 4)
    An executable C-shell script called on SIOSEIS (version 10.2.25) to: 1) read the raw SEG-Y data and create shot gathers containing two consecutive traces; 2) create a stacked trace from the two trace gathers while maintaining the navigation coordinates from the header of the first trace in each; and 3) write the stacked traces to new SEG-Y files. This stacking flow ensured that the resulting traces were spaced greater than 0.5 m apart along the trackline, which is a prerequisite for the traces to be loaded into GeoGraphix SeisVision (version R5000) for digital interpretation.

    Person who carried out this activity:

    Wayne Baldwin
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2226 (voice)
    508-457-2310 (FAX)
    wbaldwin@usgs.gov

    Date: Mar-2010 (process 2 of 4)
    An executable C-shell script called on Seismic Unix (version 4.1) to read the stacked SEG-Y files, write a Seismic Unix file, and extract SEG-Y trace header information, including shot number, longitude, latitude, year, Julian day, and time of day (UTC) to ASCII text files for each survey line. The data were filtered using AWK (no version) to save records for the first and last shots, and shots at unique longitude/latitude positions in between. Geographic coordinates (WGS84) were converted to UTM zone 16 coordinates (WGS84) using Proj (version 4.6.0), and added to the text files in two new columns.

    Person who carried out this activity:

    Wayne Baldwin
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2226 (voice)
    508-457-2310 (FAX)
    wbaldwin@usgs.gov

    Date: Mar-2010 (process 3 of 4)
    Text files created in the previous step were concatenated into a comma-delimited text file, then imported into ArcMap (version 9.2) using 'Add XY data' and saved as points (Geographic, WGS84) in the ESRI shapefile format.

    Person who carried out this activity:

    Wayne Baldwin
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2226 (voice)
    508-457-2310 (FAX)
    wbaldwin@usgs.gov

    Date: Mar-2010 (process 4 of 4)
    The shapefile created in the previous step was used as an input for VACExtras (version 1.97), a VB collection of tools developed by VeeAnn Cross (USGS-WHCMSC), which converts point data to a new polyline shapefile ('WHCMSC_SeismicTrackline.shp'), based on record order. The 'FileName' field was used to define which points were used to generate each polyline feature. Using XTools Pro (version 5.2.0) for ArcGIS desktop, the length of each polyline segment was calculated and included in the attribute field 'Length', specifying UTM, Zone 16, WGS84, and kilometers. The "find and replace" option in the ArcMap attribute table viewer was used to modify the 'ImageName' attribute to correctly reflect the relative path of the directory containing the seismic-reflection profile portable network graphic (PNG) images ('GIS_catalog\Seisimage\2010-012-FA\') by replacing the 'l', 'transit', or 'tieline' preceeding each image name with 'pathname' + the preceding characters.

    Person who carried out this activity:

    Wayne Baldwin
    U.S. Geological Survey
    Geologist
    384 Woods Hole Rd
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2226 (voice)
    508-457-2310 (FAX)
    wbaldwin@usgs.gov

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

    Stockwell, John, 2008, CWP/SU: Seismic Uni*x: Center for Wave Phenomena - Colorado School of Mines, Golden, CO.

    Online Links:

    Henkart, Paul, 2007, SIOSEIS: Scripps Institution of Oceanography, University of California - San Diego, LaJolla, CA.

    Online Links:

    Norris, Michael W. , and Faichney, Alan K. , 2002, SEGY Rev.1 Data Exchange Format1: Society of Exploration Geophysicists, Tulsa, OK.

    Online Links:

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

  1. How well have the observations been checked?

    All attributes were checked in a consistent manner.

  2. How accurate are the geographic locations?

    The SB-512i was mounted on a catamaran and towed at the sea surface approximately 50 m astern of the R/V Tommy Munro. Position data were provided by a Differential Global Positioning System (DGPS) navigation receiver mounted on the catamaran, and data were transmitted to the acquisition computer on the vessel via a 2.4 GHz radio link. The SonarWiz.MAP +SBP acquisition software logged the navigation coordinates (in arc-seconds) to individual trace headers. Positional accuracy is assumed to be better than 10 m.

  3. How accurate are the heights or depths?

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

    Sections of tracklines where navigation was recorded but no seismic data were logged are not included.

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

    Any spurious data points were removed during processing. For each seismic trackline there is one seismic-profile image that is hyperlinked by the field 'ImageName'. No duplicates exist.

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:
The Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.

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

    Elizabeth A. Pendleton
    U.S. Geological Survey
    Geologist
    384 Woods Hole Road
    Woods Hole, MA 02543-1598
    USA

    508-548-8700 x2259 (voice)
    (508)-457-2310 (FAX)
    ependleton@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?

    Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. 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?

    This zip file contains data available in Environmental Systems Research Institute (ESRI) point 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 the 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: 29-Apr-2011
Metadata author:
Elizabeth A. Pendleton
U.S. Geological Survey
Geologist
384 Woods Hole Road
Woods Hole, MA 02543-1598
USA

508-548-8700 x2259 (voice)
(508)-457-2310 (FAX)
ependleton@usgs.gov

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:

Generated by mp version 2.8.14 on Fri Apr 29 12:17:26 2011