Isopachs--Bolinas to Pescadero, California

Frequently anticipated questions:


What does this data set describe?

Title: Isopachs--Bolinas to Pescadero, California
Abstract:
This part of DS 781 presents data for the isopachs for the Bolinas to Pescadero, California, region. The vector data file is included in "Isopachs_BolinastoPescadero.zip," which is accessible from https://pubs.usgs.gov/ds/781/BolinasToPescadero/data_catalog_BolinasToPescadero.html.
As part of the USGS's California Seafloor Mapping Program, a 50-m grid of sediment thickness for the seafloor within the 3-nautical-mile limit of California's State Waters between offshore Offshore Bolinas and offshore Pescadero was generated from seismic-reflection data collected between 2006 and 2010, supplemented with outcrop and geologic structure (fault) information following the methodology of Wong (2012).
Reference Cited: Wong, F. L., Phillips, E.L., Johnson, S.Y., and Sliter, R.W., 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 2012-1161, 16 p. (available at https://pubs.usgs.gov/of/2012/1161/)
Supplemental_Information:
Additional information about the field activities from which this data set was derived are available online at
https://cmgds.er.usgs.gov/fan_info.php?fan=F207NC https://cmgds.er.usgs.gov/fan_info.php?fan=L106SF https://cmgds.er.usgs.gov/fan_info.php?fan=S809NC https://cmgds.er.usgs.gov/fan_info.php?fan=S1510NC https://cmgds.er.usgs.gov/fan_info.php?fan=S1610NC
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 Esri format, this metadata file may include some Esri-specific terminology.
  1. How might this data set be cited?
    Watt, Janet T., Hartwell, Stephen R., Johnson, Samuel Y., Sliter, Ray W., Phillips, Eleyne L., Ross, Stephanie L., and Chin, John L., 2014, Isopachs--Bolinas to Pescadero, California: Data Series DS 781, U.S. Geological Survey, Reston, VA.

    Online Links:

    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: -122.784697
    East_Bounding_Coordinate: -122.407086
    North_Bounding_Coordinate: 37.946123
    South_Bounding_Coordinate: 37.229799
  3. What does it look like?
    https://pubs.usgs.gov/ds/781/BolinasToPescadero/images/Isopachs_BolinasToPescadero.jpg (JPEG)
    map of sediment thickness contours
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 2007
    Ending_Date: 2010
    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 (483)
    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 50.000000
      Ordinates (y-coordinates) are specified to the nearest 50.000000
      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.
  7. How does the data set describe geographic features?
    isopachs
    lines of equal thickness (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: Esri) sequential feature numbers
    CONTOUR
    line of equal thickness (Source: U.S. Geological Survey) thickness measure
    Type
    Type of contour (Source: U.S. Geological Survey)
    ValueDefinition
    IndexContour at 10m interval
    IntermediateContours at 2.5m interval

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, Pacific Coastal and Marine Science Center
    Attn: PCMSC Science Data Coordinator
    2885 Mission Street
    Santa Cruz, CA
    US

    831-427-4747 (voice)
    pcmsc_data@usgs.gov

Why was the data set created?

These data are intended for science researchers, students, policy makers, and the general public. This information is not intended for navigational purposes. 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-15-10-NC (source 1 of 15)
    U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), 2011, Geophysical data from field activity S-15-10-NC: 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
    F-2-07-NC (source 2 of 15)
    U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), 2011, Geophysical data from field activity F-2-07-NC: 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
    L-1-06-NC (source 3 of 15)
    U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), 2011, Geophysical data from field activity L-1-06-NC: 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
    S-16-10-NC (source 4 of 15)
    U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), 2011, Geophysical data from field activity S-16-10-NC: 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
    S-8-09-NC (source 5 of 15)
    U.S. Geological Survey (USGS), Coastal and Marine Geology Program (CMGP), 2011, Geophysical data from field activity S-8-09-NC: 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
    BolinasGeology (source 6 of 15)
    Johnson, S.Y., Greene, H.G., Manson, M.W., Hartwell, S.R., Endris, C.A., and Watt, J.T., 2014, Geology and geomorphology—Offshore of Bolinas Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: used to determine bedrock outcrops
    BolinasFaults (source 7 of 15)
    Johnson, S.Y., Greene, H.G., Manson, M.W., Hartwell, S.R., Endris, C.A., and Watt, J.T., 2014, Faults—Offshore of Bolinas Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: faults were used to interpret subsurface geologic structure
    SanFranGeology (source 8 of 15)
    Greene, H.G., Johnson, S.Y., Manson, M.W., Hartwell, S.R., Endris, C.A., and Bruns, T.R., 2014, Geology and geomorphology—Offshore of San Francisco Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: used to determine bedrock outcrops
    SanFranFaults (source 9 of 15)
    Greene, H.G., Johnson, S.Y., Manson, M.W., Hartwell, S.R., Endris, C.A., and Bruns, T.R., 2014, Faults—Offshore of San Francisco Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: faults were used to interpret subsurface geologic structure
    PacificaGeology (source 10 of 15)
    Greene, H.G., Hartwell, S.R., Manson, M.W., Johnson, S.Y., Dieter, B.E., Phillips, E.L., and Watt, J.T., 2014, Geology and geomorphology—Offshore of Pacifica Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: used to determine bedrock outcrops
    PacificaFaults (source 11 of 15)
    Greene, H.G., Hartwell, S.R., Manson, M.W., Johnson, S.Y., Dieter, B.E., Phillips, E.L., and Watt, J.T., 2014, Faults—Offshore of Pacifica Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: faults were used to interpret subsurface geologic structure
    HalfMoonBayGeology (source 12 of 15)
    Greene, H.G., Manson, M.W., Dieter, B.E., Ross, S.L., Hartwell, S.R., Johnson, S.Y., and Watt, J.T., 2014, Geology and geomorphology—Offshore of Half Moon Bay Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: used to determine bedrock outcrops
    HalfMoonBayFaults (source 13 of 15)
    Greene, H.G., Manson, M.W., Dieter, B.E., Ross, S.L., Hartwell, S.R., Johnson, S.Y., and Watt, J.T., 2014, Faults—Offshore of Half Moon Bay Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: faults were used to interpret subsurface geologic structure
    SanGregorioGeology (source 14 of 15)
    Watt, J.T., Greene, H.G., Hartwell, S.R., Endris, C.A., Ross, S.L., Phillips, E.L., and Dieter, B.E., 2013, Geology and geomorphology—Offshore of San Gregorio Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: used to determine bedrock outcrops
    SanGregorioFaults (source 15 of 15)
    Greene, H.G., Manson, M.W., Dieter, B.E., Ross, S.L., Hartwell, S.R., Johnson, S.Y., and Watt, J.T., 2013, Faults—Offshore of San Gregorio Map Area, California: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: shapefile
    Source_Contribution: faults were used to interpret subsurface geologic structure
  2. How were the data generated, processed, and modified?
    Date: 2011 (process 1 of 5)
    Water bottom (seabed) and depth to base of the Last Glacial Maximum (LGM) horizons were digitized from seismic-reflection data using Seisworks software. The difference between the two horizons was exported from Seisworks for every shot point as XY coordinates (UTM Zone 10) and two-way travel time (TWT). The thickness was determined by applying a sound velocity to the TWT of 1,500 m/sec in water and 1,600 m/sec velocity in sediment, resulting in sediment thickness values. Data sources used in this process:
    • S-8-09-NC, L-1-06-NC, S-16-10-NC, F-2-07-NC, S-15-10-NC
    Date: 2012 (process 2 of 5)
    XY locations and sediment thickness values Z were imported to ArcGIS format as points and interpolated to a preliminary surface with TopoRaster from which isopachs (thickness contours) were extracted at 2.5 m intervals. Further refinement of the sediment thickness map (see https://pubs.usgs.gov/ds/781/BolinasToPescadero/data/SedimentThickness_BolinasToPescadero.zip) and the isopach shapefile was accomplished through several iterations of manual editing to incorporate geology and fault information following the methodology of Wong (2012; see http://pubs.usgs.gov/of/2012/1161/). Data sources used in this process:
    • S-8-09-NC, L-1-06-NC, S-16-10-NC, F-2-07-NC, S-15-10-NC, BolinasFaults, SanFranFaults, PacificaFaults, HalfMoonBayFaults, SanGregorioFaults, BolinasGeology, SanFranGeology, PacificaGeology, HalfMoonBayGeology, SanGregorioGeology
    Date: 05-Oct-2017 (process 3 of 5)
    Modified Distribution_Information section in metadata to facilitate data download. Person who carried out this activity:
    U.S. Geological Survey
    Attn: Alan O. Allwardt
    Contractor -- Information Specialist
    2885 Mission Street
    Santa Cruz, CA

    831-460-7551 (voice)
    831-427-4748 (FAX)
    aallwardt@usgs.gov
    Date: 07-May-2018 (process 4 of 5)
    Metadata was modified to bring up to current USGS PCMSC standards. USGS Thesaurus and keywords were added, and Process Steps were refined. Minor typos were corrected. No data information was changed. Person who carried out this activity:
    Susan A Cochran
    U.S. Geological Survey, Pacific Coastal and Marine Science Center
    Geologist
    2885 Mission Street
    Santa Cruz, CA
    USA

    (831) 460-7545 (voice)
    scochran@usgs.gov
    Date: 12-Sep-2018 (process 5 of 5)
    Minor typos were corrected. No data information was changed. Person who carried out this activity:
    Susan A Cochran
    U.S. Geological Survey, Pacific Coastal and Marine Science Center
    Geologist
    2885 Mission Street
    Santa Cruz, CA
    USA

    (831) 460-7545 (voice)
    scochran@usgs.gov
  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?
  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: none
Use_Constraints:
USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey
    345 Middlefield Rd
    Menlo Park, CA
    USA

    (650) 329-4309 (voice)
  2. What's the catalog number I need to order this data set? The .zip file (Isopachs_BolinasToPescadero.zip) includes the .aux, .dbf, .shp, .shx, .sbx, and .sbn files, as well as FGDC-compliant metadata for the Isopach data layer of Bolinas to Pescadero, California.
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by 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.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 12-September-2018
Metadata author:
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Attn: PCMSC Science Data Coordinator
2885 Mission Street
Santa Cruz, CA
US

831-427-4747 (voice)
pcmsc_data@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)

Generated by mp version 2.9.49 on Wed Sep 12 10:15:07 2018