Transgressive Contours--Salt Point to Drakes Bay, California

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What does this data set describe?

Title: Transgressive Contours--Salt Point to Drakes Bay, California
Abstract:
This part of DS 781 presents data for the transgressive contours for the Salt Point to Drakes Bay, California, region. The vector file is included in "TransgressiveContours_SaltPointToDrakesBay.zip," which is accessible from http://pubs.usgs.gov/ds/781/SaltPointToDrakesBay/data_catalog_SaltPointToDrakesBay.html.
As part of the USGS's California State Waters Mapping Project, a 20-m grid of depth to the transgressive surface of the last glacial maximum was generated for the areas within the 3-nautical mile limit between Salt Point and Drakes Bay was generated from seismic-reflection data collected in 2009 (USGS activity (S-8-09-NC) supplemented with outcrop and geologic structure from DS 781. The resulting grid covers an area of approximately 550 sq km. The depth to the transgressive surface of the Last Glacial Maximum ranges between 0 and 102 meters.
Supplemental_Information:
Sediment thickness and volume within each of the map areas
 Salt Point    38.639622 38.479620 -123.482704 -123.278809
 Fort Ross     38.556494 38.396794 -123.305678 -123.102404
 Bodega Bay    38.411542 38.252067 -123.172536 -122.969899
 Tomales Point 38.255180 38.095716 -123.097226 -122.895023
 Point Reyes   38.098263 37.938810 -123.094511 -122.892742
 Drakes Bay    38.038192 37.878737 -122.966411 -122.764735
     depth to transgressive surface
                  Area
  Map block      (sq km)  MIN    MAX    MEAN    STD
  Salt Point      117    -110.0  -0.2  -82.8   21.7
  Fort Ross       100    -102.1   0.0  -65.6   26.0
  Bodega Bay      128    -100.7   2.2  -52.2   28.3
  Tomales Point   108    -86.5   -4.4  -49.2   19.5
  Point Reyes     175    -89.5   -0.1  -52.1   22.7
  Drakes Bay       89    -75.8   -1.1  -38.0   12.2
Additional information about the field activities from which this data set was derived are available online at
 http://walrus.wr.usgs.gov/infobank/s/s809nc/html/s-8-09-nc.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 might this data set be cited?
    Johnson, Samuel Y., Hartwell, Stephen R., Watt, Janet T., and Sliter, Ray W., 2014, Transgressive Contours--Salt Point to Drakes Bay, California:.

    This is part of the following larger work.

    Golden, Nadine E., 2013, California State Waters Map Series Data Catalog: Data Series DS 781, U.S. Geological Survey, Reston, VA.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -123.473993
    East_Bounding_Coordinate: -122.762732
    North_Bounding_Coordinate: 38.640196
    South_Bounding_Coordinate: 37.868433
  3. What does it look like?
    http://pubs.usgs.gov/ds/781/SaltPointToDrakesBay/images/TransgressiveContours_SaltPointToDrakesBay.jpg (JPEG)
    map of sediment thickness contours
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 2009
    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 (779)
    2. What coordinate system is used to represent geographic features?
      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 10
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -117.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000
      Planar coordinates are encoded using row and column
      Abscissae (x-coordinates) are specified to the nearest 20.000000
      Ordinates (y-coordinates) are specified to the nearest 20.000000
      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.
      Vertical_Coordinate_System_Definition:
      Depth_System_Definition:
      Depth_Datum_Name: NAVD88
      Depth_Resolution: 20.0
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Implicit coordinate
  7. How does the data set describe geographic features?
    Transgressive_contours
    lines of equal depth to transgressive surface (Source: standard sedimentology)
    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 feature number (Source: this study) sequential feature numbers
    CONTOUR
    Lines of equal depth to transgressive surface (Source: this study) depth to transgressive surface using a 5 meter contour interval
    Type
    Type of contour (Source: This report)
    ValueDefinition
    IndexContour at 10m interval
    IntermediateContours at 5m interval

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Samuel Y. Johnson
    • Stephen R. Hartwell
    • Janet T. Watt
    • Ray W. Sliter
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    U.S. Geological Survey, Coastal and Marine Geology Program
    Attn: Stephen Hartwell
    Geologist
    400 Natural Bridges Drive
    Santa Cruz, CA
    USA

    (831) 460-7814 (voice)
    (831) 427-4748 (FAX)
    shartwell@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?
    S-8-09-NC (source 1 of 1)
    U.S. Geological Survey (USGS) , Coastal and Marine Geology Program (CMGP), 2013, Seismic-reflection data acquisition data of field activity S-8-09-NC Stinson Beach to point Arena 09/08/2009 to 09/30/2009: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG), Menlo Park, CA.

    Online Links:

    Type_of_Source_Media: ASCII lat/long shot point files
    Source_Contribution:
    Digital seismic data used to interpret subsurface geologic structure
  2. How were the data generated, processed, and modified?
    Date: 2013 (process 1 of 4)
    Chirp and sparker seismic-reflection data from USGS field activity S-8-09-NC were imported to SEISWORKS.
    Date: 2013 (process 2 of 4)
    Seabed and depth to Last Glacial Maximum horizons digitized in Seisworks.
    Date: 2013 (process 3 of 4)
    Data exported and converted with 1500m/sec velocity in water and 1600 m/sec velocity in sediment.
    Date: 2013 (process 4 of 4)
    X, Y locations and sediment thickness value Z imported to ArcGIS format as points, interpolated to preliminary surface with TopoRaster. Because processing of the related sediment thickness map resulted in an interpolated surface that diverged from the data exported from Seisworks, the final transgressive surface was calculated by subtracting sediment thickness from multibeam bathymetry.
  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. 50-m cell size for interpolation is better supported along track than between.
  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?
    Estimated to be approximately 1 m, along the track lines where data is well constrained, but may be much greater in areas where interpolation occurred.
  4. Where are the gaps in the data? What is missing?
    Sediment thickness data points exported from Seisworks profiling software were processed within the California 3-nmi limit.
  5. How consistent are the relationships among the observations, including topology?
    All vector geometry and attributes present.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints:
If physical samples or materials are available, constraints on their on-site access are described in "WR CMG Sample Distribution Policy" at URL: http://walrus.wr.usgs.gov/infobank/programs/html/main/sample-dist-policy.html
Use_Constraints:
This information is not intended for navigational purposes.
Read and fully comprehend the metadata prior to data use. Uses of these data should not violate the spatial resolution of the data. Where these data are used in combination with other data of different resolution, the resolution of the combined output will be limited by the lowest resolution of all the data.
Acknowledge the U.S. Geological Survey in products derived from these data. Share data products developed using these data with the U.S. Geological Survey.
This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.
Although this Federal Geographic Data Committee-compliant metadata file is intended to document these data in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey, Coastal and Marine Geology Program
    Attn: Stephen Hartwell
    Geologist
    400 Natural Bridges Drive
    Santa Cruz, CA
    USA

    (831) 460-7814 (voice)
    (831) 427-4748 (FAX)
    shartwell@usgs.gov
  2. What's the catalog number I need to order this data set? TransgressiveContours_SaltPointToDrakesBay.zip
  3. What legal disclaimers am I supposed to read?
    These databases, identified as transgressive contours for the Salt Point to Drakes Bay Region, California have been approved for release and publication by the U.S. Geological Survey (USGS). Although these databases have been subjected to rigorous review and are substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.
    Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein.
    Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
    These data are not intended for navigational use.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 2013
Last Reviewed: 2013
Metadata author:
U.S. Geological Survey, Coastal and Marine Geology Program
Attn: Stephen Hartwell
Geologist
400 Natural Bridges Drive
Santa Cruz, CA
USA

(831) 460-7814 (voice)
(831) 427-4748 (FAX)
shartwell@usgs.gov
Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)

This page is <https://cmgds.marine.usgs.gov/catalog/pcmsc/cal_state_waters/TransgressiveContours_SaltPointToDrakesBay_metadata.faq.html>
Generated by mp version 2.9.49 on Fri Sep 13 15:01:02 2019