Offshore sediment thickness data in California State Waters between Refugio and Hueneme Canyon, California (sbsedthkpt).

Frequently anticipated questions:

What does this data set describe?

Title:
Offshore sediment thickness data in California State Waters between Refugio and Hueneme Canyon, California (sbsedthkpt).
Abstract:
As part of the USGS's California State Waters Mapping Project, sediment thickness for the seafloor within the 3-nautical mile limit between Gaviota and Hueneme Canyon was extracted from seismic-reflection data collected in 2007 (USGS activity (Z-3-07-SC) and 2008 (S-7-08-SC). Sediment thickness ranges from 0 to 65 m with a mean of 12 m and a standard deviation of 15 m.
Supplemental_Information:
Additional information about the field activities from which this data set was derived are available online at 
 <http://walrus.wr.usgs.gov/infobank/z/z307sc/html/z-3-07-sc.meta.html>
 <http://walrus.wr.usgs.gov/infobank/s/s708sc/html/s-7-08-sc.meta.html>
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology.
  1. How should this data set be cited?

    Wong, Florence L. , Phillips, Eleyne L. , Johnson, Samuel Y. , and Sliter, Ray W. , 2012, Offshore sediment thickness data in California State Waters between Refugio and Hueneme Canyon, California (sbsedthkpt).: U.S. Geological Survey Open-File Report OF 2012-1161, U.S. Geological Survey, Menlo Park, California.

    Online Links:

    This is part of the following larger work.

    Florence L. Wong, Eleyne L. Phillips, Samuel Y. Johnson, and Ray W. Sliter, 2012, Modeling of depth to base of Last Glacial Maximum and seafloor sediment thickness for the California State Waters Map Series, eastern Santa Barbara Channel, California: U.S. Geological Survey Open-File Report OF 2012-1161, U.S. Geological Survey, Menlo Park, California.

    Online Links:

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -120.206232
    East_Bounding_Coordinate: -119.123028
    North_Bounding_Coordinate: 34.492447
    South_Bounding_Coordinate: 34.027787

  3. What does it look like?

    sbsedthkpt.jpg (JPEG)
    map of sediment thickness points rendered by color

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

    Beginning_Date: 2007
    Ending_Date: 2009
    Currentness_Reference: ground condition

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

    Geospatial_Data_Presentation_Form: map

  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):

      • Entity point (924661)

    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?

    sbsedthkpt
    sediment thickness at point locations (Source: this study)

    FID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    SEDTHKPTLL
    line number in Seisworks export file (Source: none)

    line numbers in file

    X_UTM1184
    X-coordinate in UTM zone 11 coordinates (Source: standard usage)

    Coordinates defining the features.

    Y_UTM1184
    Y-coordinate in UTM zone 11 coordinates (Source: standard usage)

    Coordinates defining the features.

    THK_M
    sediment thickness THK_M0 <= 0.1 increased to 0.1 (Source: this study)

    sediment thickness value

    THK_M0
    sediment thickness in meters as exported from Seisworks (Source: ESRI)

    sediment thickness value

    LONG84
    x-coordinate (longitude) in geographic coordinates, WGS84 (Source: standard usage)

    Coordinates defining the features.

    LAT84
    Y-coordinate (latitude) in geographic coordinates, WGS84 (Source: standard usage)

    Coordinates defining the features.

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?

    U.S. Geological Survey
    Attn: Florence L. Wong
    Geologist
    345 Middlefield Road, MS 999
    Menlo Park, CA 94025
    USA

    650-329-5327 (voice)
    fwong@usgs.gov

Why was the data set created?

These data are intended for science researchers, students, policy makers, and the general public. The data can be used with geographic information systems (GIS) software to display geologic and oceanographic information.

How was the data set created?

  1. From what previous works were the data drawn?

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

    Date: 2011 (process 1 of 6)
    Chirp and sparker seismic-reflection data from USGS field activity Z-3-07-SC and chirp data from field activity S-7-08-SC were imported to SEISWORKS. (Ray Sliter, rsliter@usgs.gov)

    Date: 2011 (process 2 of 6)
    Seabed and depth to Last Glacial Maximum horizons digitized in Seisworks (S.Y. Johnson, sjohnson@usgs.gov)

    Date: 2011 (process 3 of 6)
    Data exported and converted with 1500m/sec velocity in water and 1600 m/sec velocity in sediment. (Ray Sliter, rsliter@usgs.gov).

    Date: 2011 (process 4 of 6)
    X, Y locations and sediment thickness value Z imported to ArcGIS format as points (Florence Wong, fwong@usgs.gov)

    Date: 09-Jun-2011 (process 5 of 6)
    Metadata imported.

    Data sources used in this process:

    • Q:\sbsedthk\metadata\covsfinal\sedthick\metadata.xml

    Date: 09-Jun-2011 (process 6 of 6)
    Metadata imported.

    Data sources used in this process:

    • d:\TEMP\xml257.tmp

  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?

    Data points are approximately 1 m apart along tracklines and 1000-2000 m apart between tracks.

  2. How accurate are the geographic locations?

    The chirp sonar instrument is deployed under the research vessel with about 10m of variation in position. The sparker position may vary as much as 20m from the navigation reference on the vessel.

  3. How accurate are the heights or depths?

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

    All points exported from Seisworks present

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

    Point features 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: Not to be used for navigation.

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

    United States Geological Survey (USGS) Coastal and Marine Geology (CMG)
    Attn: Florence L. Wong
    Geologist, GIS Coordinator
    USGS, MailStop 999, 345 Middlefield Road
    Menlo Park, CA 94025-3561
    USA

    (650) 329-5327 (voice)
    (650) 329-5190 (FAX)
    fwong@usgs.gov

  2. What's the catalog number I need to order this data set?

    Downloadable Data. USGS OF 2012-1161

  3. What legal disclaimers am I supposed to read?

    Please recognize the U.S. Geological Survey (USGS) as the source of this information.
    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.
    The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials.

  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 12-May-2011
Last Reviewed: 19-Oct-2011
Metadata author:
U.S. Geological Survey
Attn: Florence L. Wong
Geologist
345 Middlefield Road, MS 999
Menlo Park, California 94025
USA

650-329-5327 (voice)
fwong@usgs.gov

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

Generated by mp version 2.9.15 on Thu Aug 2 12:54:37 2012