Quaternary faults offshore of California

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What does this data set describe?

Title: Quaternary faults offshore of California
Abstract:
A comprehensive map of Quaternary faults has been generated for offshore of California. The Quaternary fault map includes mapped geometries and attribute information for offshore fault systems located in California State and Federal waters. The polyline shapefile has been compiled from previously published mapping where relatively dense, high-resolution marine geophysical data exist. The data are also available in kml format and are accompanied by a pdf containing citations for the compiled source data. In the last decade, a number of new marine geophysical datasets collected by the U.S. Geological Survey (USGS), the Ocean Exploration Trust, and other organizations has led to substantially improved high-resolution mapping of the seafloor in areas including California's mainland State waters and the southern California continental borderland. Data include comprehensive multibeam bathymetry, seismic-reflection, and marine magnetic data in numerous offshore areas. Most of these data have been processed, merged, and released by the USGS in maps, data releases, and journal publications in support of the California Seafloor Mapping Program and the U.S. West Coast and Alaska Marine Geohazards Project. Improved data coverage has allowed researchers to better map offshore faults in areas previously unmapped or covered only by low-resolution data. Additionally, subsurface imaging and seafloor sampling has led to better understanding of fault kinematics and recency of deformation, which are critical for accurately assessing California's seismic and coastal hazards.
Supplemental_Information:
Additional information about the field activities from which these interpreted data were derived is available in the data sources. See the table of attributes included in the data for specific fault source information, and the associated PDF for a comprehensive list of sources used to compile this dataset. 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 dataset 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?
    Walton, Maureen A.L., Papesh, Antoinette G., Johnson, Samuel Y., Conrad, James E., and Brothers, Daniel S., 20200430, Quaternary faults offshore of California: data release DOI:10.5066/P91RYEZ4, U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, CA.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -124.444403
    East_Bounding_Coordinate: -117.117080
    North_Bounding_Coordinate: 40.276898
    South_Bounding_Coordinate: 32.335489
  3. What does it look like?
    https://www.sciencebase.gov/catalog/file/get/5d38b842e4b01d82ce8b9b56?name=qFaults_offshore_california_2020_map.png&allowOpen=true (PNG)
    Map of qFaults Offshore 2020 coverage
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 1982
    Ending_Date: 2020
    Currentness_Reference:
    Published years of the compiled data. See PDF for comprehensive list of sources used to compile this dataset.
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: polyline shapefile, kml
  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 (1093)
    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 0.0001. Longitudes are given to the nearest 0.0001. 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 6378137.0.
      The flattening of the ellipsoid used is 1/298.257223563.
  7. How does the data set describe geographic features?
    qFaults_Offshore_California
    polylines representing mapped faults (Source: U.S. Geological Survey)
    FID
    internal feature number (Source: Esri) Sequential unique whole numbers that are automatically generated.
    Shape
    feature geometry (Source: Esri) feature type
    FAULT_NAME
    Name of the fault strand as commonly reported in peer-reviewed publications. (Source: U.S. Geological Survey and California Geological Survey) Entry appended with 'fault'. If there is no specific name for the fault strand, this entry is populated with the fault zone name; entry appended with 'fault zone'. If there is no specific fault zone name, this entry is populated with 'unspecified'.
    FAULT_ZONE
    Name of the fault zone as commonly reported in peer-reviewed publications. (Source: U.S. Geological Survey and California Geological Survey) Entry appended with 'fault zone'. If there is no specific fault zone name, this entry is populated with 'unspecified'.
    SECTION_NA
    Name of the section of the fault strand. (Source: U.S. Geological Survey and California Geological Survey) Sections can be differentiated based on slip rate changes, strike changes, or name changes; sections are not meant to represent rupture segments or barriers. If there is no specific section name of the fault strand, this entry is left blank.
    OTHER_NAME
    other names commonly used in the literature for the fault strand (Source: U.S. Geological Survey) If other names have been used for the fault strand, these other names are reported in this field. If no other names have been reported, this entry is left blank.
    FAULT_ID
    U.S. Geological Survey defined numerical fault identifier (Source: U.S. Geological Survey) Values are taken from U.S. Geological Survey Quaternary Fault and Fold Database reference ID attribute where the fault zone matches.
    FLT_AGE
    age category of the fault (Source: U.S. Geological Survey and California Geological Survey)
    ValueDefinition
    HISHistoric. To be classified as 'historic', faults need to have strong and confident evidence of historic rupture on the fault. Strong and confident evidence includes evidence of rupture greater than magnitude 6, or surface rupture of an adjacent onshore strand.
    HOLHolocene or younger. Faults in this dataset less than 15 Ka are considered to be Holocene.
    LTQTLate Quaternary. Faults in this dataset greater than 15 Ka and less than 130 Ka are considered to be Late Quaternary.
    QTQuaternary. Use if age is known to be Quaternary but there are no other age constraints.
    PREQTpre-Quaternary. Use pre-Quaternary for faults that have been previously mapped as Quaternary, and new mapping shows them as pre-Quaternary.
    SLIP_RATE
    Categorization of net slip including horizontal and vertical components. Use the same slip rate for all strands of a fault zone unless a specific strand is superseded by a different slip rate value from the literature. If a slip rate spans multiple categories, use the category of the preferred value. Categories are used to account for uncertainty and variations in slip rates. Category values are in millimeters per year. (Source: California Geological Survey)
    ValueDefinition
    <0.2Net slip is less than 0.2 millimeters per year.
    0.2-1.0Net slip is between 0.2 and 1.0 millimeters per year.
    1-5Net slip is between 1 and 5 millimeters per year.
    >5Net slip greater than 5 millimeters per year.
    unspecifiedUnspecified slip rate.
    SLIP_SENSE
    the sense of slip along the fault plane (Source: California Geological Survey) Descriptors are D, S, R, N and unspecified for dextral, sinistral, reverse, normal, and unspecified, respectively. Two letters are included where the motion is oblique, with the dominant motion as the first letter. The same slip sense is used for all strands of a fault zone unless a specific strand is superseded by a different slip sense value from the literature.
    SHAPE_LENG
    length of fault strand (Source: Esri) GIS calculated value of the length of the fault strand, reported in kilometers.
    MAPPED_SCA
    the scale of mapping or published map source (Source: U.S. Geological Survey) Scale of published map source where available; if mapping was completed in GIS, least precise scale used for mapping is reported.
    LINE_TYPE
    the categorization of mapping accuracy based on data coverage and scale of mapping of the fault, can be used as a representation rule in the GIS file to indicate symbology (Source: U.S. Geological Survey and California Geological Survey)
    ValueDefinition
    Accurately Locateddefined where mapped scale is less than or equal to 1:50,000, see MAPPED_SCA attribute
    Approximately Locateddefined where mapped scale is greater than 1:50,000, see MAPPED_SCA attribute
    Inferreddefined where data are sparse or faults are extrapolated
    unspecifieddata unspecified
    EXPRESSION
    brief description of constraining data (Source: U.S. Geological Survey) brief description of constraining data types, approximate spacing, and resolution where applicable
    FLT_SOURCE
    citation information for fault strand geometry and attributes (Source: U.S. Geological Survey and California Geological Survey) A list of citations of sources that were used to define fault geometry and attributes. See the accompanying references PDF (qFaults_offshore_california_ 2020_references.pdf) for a comprehensive list of references.
    Entity_and_Attribute_Overview:
    Polyline shapefile and kml containing geometries and attributes of faults offshore of California.
    Entity_and_Attribute_Detail_Citation: U.S. Geological Survey

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Maureen A.L. Walton
    • Antoinette G. Papesh
    • Samuel Y. Johnson
    • James E. Conrad
    • Daniel S. Brothers
  2. Who also contributed to the data set?
    California Geological Survey (CGS)
  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

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

Why was the data set created?

The geographic information systems (GIS) shapefile presented here contains offshore fault geometries, locations, ages, slip rates, and relevant published reference information (please refer to the rest of the metadata for detailed attribute information and references). This compilation represents a significant update to previous national and regional fault datasets, which have been developed without the benefit of new high-resolution datasets. The geodatabase has been designed for easy ingestion by partners including the California Geological Survey and the USGS Quaternary Fault and Fold Database, and to be used to improve seismic hazards products, especially the USGS National Seismic Hazard Maps, the Uniform California Earthquake Rupture Forecast, and the Southern California Earthquake Center Community Fault Model. Other stakeholders include academic scientists, consultants, community planners and managers, the risk assessment community, and the general public.

How was the data set created?

  1. From what previous works were the data drawn?
    REF (source 1 of 1)
    Papesh, Antoinette, 2020, qFaults_offshore_california_2020_references.pdf: U.S. Geological Survey, online.

    Online Links:

    Type_of_Source_Media: Digital Resource
    Source_Contribution:
    qFaults_offshore_california_2020_references.pdf is a comprehensive list of referenced sources for this fault dataset.
  2. How were the data generated, processed, and modified?
    Date: 22-Mar-2020 (process 1 of 4)
    Faults geometries offshore of central California were retrieved from publications listed in the accompanying references PDF (qFaults_offshore_california_2020_references.pdf). Faults offshore of central California were digitized in UTM 10, and then projected to WGS 1984 when incorporated into this dataset. Person who carried out this activity:
    Antoinette Papesh
    U.S. Geological Survey
    Contractor
    2885 Mission Street
    Santa Cruz, CA

    831-460-7532 (voice)
    apapesh@usgs.gov
    Data sources used in this process:
    • See the 'FLT_SOURCE' attribute within the shapefile, and the accompanying references PDF for details on where to find information on specific sources used.
    Date: 22-Mar-2020 (process 2 of 4)
    Faults geometries located in the Continental Borderland offshore southern California were retrieved from the California Seafloor Mapping Program data series 781 (Golden, compiler, 2013), from publications listed in the accompanying references PDF. Faults offshore of southern California were digitized in UTM 11, and then projected to WGS 1984 when incorporated into this dataset. Person who carried out this activity:
    Antoinette Papesh
    U.S. Geological Survey
    Contractor
    2885 Mission Street
    Santa Cruz, CA

    831-460-7532 (voice)
    apapesh@usgs.gov
    Data sources used in this process:
    • See the 'FLT_SOURCE' attribute within the shapefile, and the accompanying references PDF for details on where to find information on specific sources used.
    Date: 25-Mar-2020 (process 3 of 4)
    A KML file of the fault dataset was created using GIS software. Person who carried out this activity:
    Antoinette Papesh
    U.S. Geological Survey
    Contractor
    2885 Mission Street
    Santa Cruz, CA

    831-460-7532 (voice)
    apapesh@usgs.gov
    Data sources used in this process:
    • See the 'FLT_SOURCE' attribute within the shapefile, and the accompanying references PDF for details on where to find information on specific sources used.
    Date: 19-Oct-2020 (process 4 of 4)
    Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
    vatnipp@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?
    This data and associated attributes have been compiled from a variety of publications. See the 'FLT_SOURCE' attribute within the shapefile, and the accompanying references PDF for details on where to find specific attribute accuracy information.
  2. How accurate are the geographic locations?
    This data and associated attributes have been compiled from a variety of publications. See the 'FLT_SOURCE' attribute within the shapefile, and the accompanying references PDF for details on where to find specific horizontal position accuracy information.
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
    Some pre-Quaternary fault geometries were included to reflect new research updating these faults from Quaternary to pre-Quaternary.
  5. How consistent are the relationships among the observations, including topology?
    No formal logical accuracy tests were conducted.

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.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey - ScienceBase
    Denver Federal Center, Building 810, Mail Stop 302
    Denver, CO

    1-888-275-8747 (voice)
    sciencebase@usgs.gov
  2. What's the catalog number I need to order this data set? These data are available in shapefile format (qFaults_Offshore_California_2019.shp and associated files) contained in a single zip file (qFaults_Offshore_California_2019.zip), along with CSDGM FGDC-compliant metadata, and a thumbnail map of the faults contained in the dataset, and a list of sourced references.
  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?
  5. What hardware or software do I need in order to use the data set?
    These data can be viewed with GIS software.

Who wrote the metadata?

Dates:
Last modified: 19-Oct-2020
Metadata author:
U.S. Geological Survey, Pacific Coastal and Marine Science Center
Attn: PCMSC Science Data Coordinator
2885 Mission Street
Santa Cruz, CA

831-427-4747 (voice)
pcmsc_data@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/pcmsc/DataReleases/ScienceBase/DR_P91RYEZ4/qFaults_offshore_california_2020_metadata.faq.html>
Generated by mp version 2.9.50 on Tue Sep 21 18:17:22 2021