Preliminary maps of Quaternary deposits and liquefaction susceptibility, nine-county San Francisco Bay region, California: a digital database

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What does this data set describe?

Title:
Preliminary maps of Quaternary deposits and liquefaction susceptibility, nine-county San Francisco Bay region, California: a digital database
Abstract:
This report presents a preliminary map and database of Quaternary deposits and liquefaction susceptibility for the nine-county San Francisco Bay region, together with a digital compendium of ground effects associated with past earthquakes in the region. The report consists of (1) a spatial database of fivedata layers (Quaternary deposits, quadrangle index, and three ground effects layers) and two text layers (a labels and leaders layer for Quaternary deposits and for ground effects), (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map, liquefaction interpretation, and the ground effects compendium, and (4) the databse description pamphlet.
The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment.
This new map provides a modern and regionally consistent treatment of Quaternary surficial deposits that builds on the pioneering mapping of Helley and Lajoie (Helley and others, 1979) and such intervening work as Atwater (1982), Helley and others (1994), and Helley and Graymer (1997a and b). Like these earlier studies, the current mapping uses geomorphic expression, pedogenic soils, and inferred depositional environments to define and distinguish the map units. In contrast to the twelve map units of Helley and Lajoie, however, this new map uses a complex stratigraphy of some forty units, which permits a more realistic portrayal of the Quaternary depositional system. The two colored maps provide a regional summary of the new mapping at a scale of 1:275,000, a scale that is sufficient to show the general distribution and relationships of the map units but cannot distinguish the more detailed elements that are present in the database.
The report is the product of years of cooperative work by the USGS National Earthquake Hazards Reduction Program (NEHRP) and National Cooperative Geologic Mapping Program, William Lettis and & Associates, Inc. (WLA) and, more recently, by the California Division of Mines and Geology as well. An earlier version was submitted to the Geological Survey by WLA as a final report for a NEHRP grant (Knudsen and others, 2000). The mapping has been carried out by WLA geologists under contract to the NEHRP Earthquake Program (Grants #14-08-0001-G2129, 1434-94-G-2499, 1434-HQ-97-GR-03121, and 99-HQ-GR-0095) and with other limited support from the County of Napa, and recently also by the California Division of Mines and Geology. The current map consists of this new mapping and revisions of previous USGS mapping.
Supplemental_Information:
This report has undergone two scientific peer reviews, one digital database review, and review of the digital files for functionality.
This report presents a preliminary map and database of Quaternary deposits and liquefaction susceptibility for the nine-county San Francisco Bay region, together with a digital compendium of ground effects associated with past earthquakes in the region. The report consists of (1) a spatial database of five data layers (Quaternary deposits, quadrangle index, and three ground effects layers) and two text layers (a labels and leaders layer for Quaternary deposits and for ground effects), (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map, liquefaction interpretation, and the ground effects compendium, and (4) the database description pamphlet. See the revision list (of00-444_2x) or Open-File pamphlet (of00-444_1x) for further details.
  1. How might this data set be cited?
    Knudsen, K.L., Sowers, J.M., Witter, R.C., Wentworth, C.M., Helley, E.J., Nicholson, R.S., Wright, H.M., and Brown, K.M., 2000, Preliminary maps of Quaternary deposits and liquefaction susceptibility, nine-county San Francisco Bay region, California: a digital database: U.S. Geological Survey Open-File Report 00-444, U.S. Geological Survey, Menlo Park, CA.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -121.125
    East_Bounding_Coordinate: -123.625
    North_Bounding_Coordinate: 38.866667
    South_Bounding_Coordinate: 36.866667
  3. What does it look like?
    http://pubs.usgs.gov/of/2000/of00-444/of00-444_7b.pdf (PDF)
    Quaternary Deposits Map (5.4MB)
    http://pubs.usgs.gov/of/2000/of00-444/of00-444_8b.pdf (PDF)
    Liquefaction Susceptibility Map (5.7MB)
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 01-Dec-2000
    Currentness_Reference:
    The date given is the publication date. The information in the report was current at the time of publication.
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: maps and spatial databases
  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):
      • Point
      • String
      • GT-polygon composed of chains
    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: 0.9996
      Longitude_of_Central_Meridian: -123
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 1.0
      Ordinates (y-coordinates) are specified to the nearest 1.0
      Planar coordinates are specified in METERS
      The horizontal datum used is NAD27.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.4.
      The flattening of the ellipsoid used is 1/294.98.
  7. How does the data set describe geographic features?
    SF-QUAT.PAT
    Attribute table of SF-QUAT.PAT.
    PTYPE
    Geologic unit label
    ValueDefinition
    H2Owater
    QaLatest Pleistocene to Holocene alluvium, undifferentiated
    QbLatest Pleistocene to Holocene basin deposits
    QdsLatest Pleistocene to Holocene dune sand
    QfLatest Pleistocene to Holocene alluvial fan deposits
    QhaHolocene alluvium, undifferentiated
    QhayLatest Holocene alluvial deposits, undifferentiated
    QhbHolocene basin deposits
    QhbmHolocene San Francisco Bay mud
    QhbsHolocene beach sand
    QhcModern stream channel deposits
    QhdmHolocene San Joaquin/Sacramento Delta mud and peat
    QhdsHolocene dune sand
    QhfHolocene alluvial fan deposits
    Qhf1Younger Holocene alluvial fan deposits
    Qhf2Older Holocene alluvial fan deposits
    QhfbLatest Holocene flood basin deposits
    QhfeHolocene alluvial fan-estuarine complex deposits
    QhffFine-grained Holocene alluvial fan deposits
    QhfpLatest Holocene alluvial floodplain deposits, undivided
    QhfyLatest Holocene alluvial fan deposits
    QhlHolocene alluvial fan levee deposits
    Qhl1Younger Holocene alluvial fan levee deposits
    Qhl2Older Holocene alluvial fan levee deposits
    QhlyLatest Holocene alluvial fan levee deposits
    QhtHolocene stream terrace deposits
    Qht1Younger Holocene stream terrace deposits
    Qht2Older Holocene stream terrace deposits
    QhtyLatest Holocene stream terrace deposits
    Qhty1Younger latest Holocene stream terrace deposits
    Qhty2Older latest Holocene stream terrace deposits
    QlLatest Pleistocene to Holocene alluvial fan levee deposits
    QmtPleistocene marine terrace deposits
    Qmt1Youngest (of 4) Pleistocene marine terrace deposits
    Qmt2Second youngest (of 4) Pleistocene marine terrace deposits
    Qmt3Third youngest (of 4) Pleistocene marine terrace deposits
    Qmt4Oldest (of 4) Pleistocene marine terrace deposits
    QoaEarly to late Pleistocene undifferentiated alluvial deposits
    Qoa1Younger early to late Pleistocene undifferentiated alluvial deposits
    Qoa2Older early to late Pleistocene undifferentiated alluvial deposits
    QofEarly to late Pleistocene alluvial fan deposits
    Qof1Younger Early to late Pleistocene alluvial fan deposits
    Qof2Older Early to late Pleistocene alluvial fan deposits
    QopEarly to late Pleistocene pediment deposits
    QotEarly to late Pleistocene stream terrace deposits
    QpaLatest Pleistocene alluvium, undifferentiated
    QpbLatest Pleistocene basin deposits
    QpfLatest Pleistocene alluvial fan deposits
    QptLatest Pleistocene stream terrace deposit
    QtLatest Pleistocene to Holocene stream terrace deposits
    acArtificial stream channel
    adsDredge spoils
    afArtificial fill
    afbmArtificail fill over San Francisco Bay mud
    alfArtificial fill, levee
    brbedrock
    gqGravel quarry
    nmnot mapped
    LIQ
    Liquefaction susceptibility
    ValueDefinition
    HHigh Susceptibility
    LLow Susceptibility
    MModerate Susceptibility
    NMNot mapped
    VHVery High Susceptibility
    VLVery Low Susceptibility
    Wwater
    LIQ-SOURCE
    whether a custom LIQ value was assigned
    ValueDefinition
    1custom LIQ value assigned
    SF-QUAT.AAT
    Attribute table of SF-QUAT.
    LTYPE
    Type of geologic or geographic feature denoted by a line in the database.
    ValueDefinition
    contact, approx. locateddepositional contact, location uncertainty greater than about +/- 100 m
    contact, well locateddepositional contact, location uncertainty less than about +/- 100 m
    contact, concealeddepositional contact concealed beaneath water, fill, or levee
    county lineBoundary of nine-county region, from 1:24,000 USGS DLGs and published paper topographic maps
    map boundaryExterior boundary of 1:24,000 quadrangles composing the map area
    scratch boundaryBoundary without geologic attribute, here connecting mismatch of contacts or units at 7.5-minute quadrangle boundary
    water boundaryBoundary of open water from 1:24,000 USGS DLGs and published paper topographic maps
    water boundary, 1800sLandward margin of tidal marsh bordering San Francisco Bay in the late 19th century, mainly from Nichols and Wright, 1971
    Entity_and_Attribute_Overview:
    Attribute file sf-elns.dbf
      Number of fields: 28
      Number of records: 76
    FNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    TNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    RPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LENGTH is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    EFFECTS_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    EFFECTS_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    STA is a String of width 5.
      Documented as an Enumerated_Domain
      There are 47 distinct values.
      10 values occur more than once in the data.
    EQK is a String of width 10.
      Documented as an Enumerated_Domain
      There are 9 distinct values.
      2 values occur more than once in the data.
    SRC is a String of width 30.
      Documented as an Enumerated_Domain
      There are 2 distinct values.
      2 values occur more than once in the data.
    KIND is a String of width 12.
      Documented as an Enumerated_Domain
      There are 2 distinct values.
      2 values occur more than once in the data.
    ACC is a String of width 5.
      Documented as an Enumerated_Domain
      There are 26 distinct values.
      13 values occur more than once in the data.
    EXT is a String of width 10.
      Documented as an Enumerated_Domain
      There are 4 distinct values.
      1 values occur more than once in the data.
    COMM is a String of width 50.
      Documented as an Enumerated_Domain
      There are 5 distinct values.
      1 values occur more than once in the data.
    FIELD is a String of width 50.
      Documented as an Enumerated_Domain
      There are 5 distinct values.
      1 values occur more than once in the data.
    LS_H is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    LS_S is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    LATSP is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    SETL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    CRK_ST is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    CRK_GND is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    PIPE is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    BOIL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    WELL is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    MISC is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    ABS is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    EFFECTS is a String of width 35.
      Documented as an Enumerated_Domain
      There are 19 distinct values.
      11 values occur more than once in the data.
    SF is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    Attribute file sf-epts.dbf
      Number of fields: 25
      Number of records: 401
    AREA is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    PERIMETER is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    EFFECTS_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    EFFECTS_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    STA is a String of width 5.
      Documented as an Enumerated_Domain
      There are 257 distinct values.
      64 values occur more than once in the data.
    EQK is a String of width 10.
      Documented as an Enumerated_Domain
      There are 18 distinct values.
      9 values occur more than once in the data.
    SRC is a String of width 30.
      Documented as an Enumerated_Domain
      There are 2 distinct values.
      2 values occur more than once in the data.
    KIND is a String of width 12.
      Documented as an Enumerated_Domain
      There are 4 distinct values.
      3 values occur more than once in the data.
    ACC is a String of width 5.
      Documented as an Enumerated_Domain
      There are 19 distinct values.
      17 values occur more than once in the data.
    EXT is a String of width 10.
      Documented as an Enumerated_Domain
      There are 2 distinct values.
      1 values occur more than once in the data.
    COMM is a String of width 50.
      Documented as an Enumerated_Domain
      There are 18 distinct values.
      2 values occur more than once in the data.
    FIELD is a String of width 50.
      Documented as an Enumerated_Domain
      There are 18 distinct values.
      6 values occur more than once in the data.
    LS_H is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    LS_S is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    LATSP is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    SETL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    CRK_ST is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    CRK_GND is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    PIPE is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    BOIL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    WELL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    MISC is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    ABS is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    EFFECTS is a String of width 35.
      Documented as an Enumerated_Domain
      There are 50 distinct values.
      24 values occur more than once in the data.
    SF is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    Attribute file sf-hpys.dbf
      Number of fields: 25
      Number of records: 7
    AREA is a Double of width 20 and precision 5.
      Intrinsic to ArcInfo, not documented here.
    PERIMETER is a Double of width 20 and precision 5.
      Intrinsic to ArcInfo, not documented here.
    EFHSPYS_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    EFHSPYS_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    STA is a String of width 5.
      Documented as an Enumerated_Domain
      There are 7 distinct values.
      Each value occurs only once in the data.
    EQK is a String of width 10.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "1906".
    SRC is a String of width 30.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "Youd and Hoose, 1978".
    KIND is a String of width 12.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "area".
    ACC is a String of width 5.
      Documented as an Enumerated_Domain
      There are 6 distinct values.
      1 values occur more than once in the data.
    EXT is a String of width 10.
      Documented as an Enumerated_Domain
      For all records in the file this field is empty.
    COMM is a String of width 50.
      Documented as an Enumerated_Domain
      There are 4 distinct values.
      2 values occur more than once in the data.
    FIELD is a String of width 50.
      Documented as an Enumerated_Domain
      For all records in the file this field is empty.
    LS_H is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    LS_S is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    LATSP is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    SETL is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    CRK_ST is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    CRK_GND is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    PIPE is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    BOIL is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    WELL is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    MISC is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    ABS is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    EFFECTS is a String of width 35.
      Documented as an Enumerated_Domain
      There are 5 distinct values.
      1 values occur more than once in the data.
    SF is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    Attribute file sf-ilns.dbf
      Number of fields: 9
      Number of records: 1555
    FNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    TNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    RPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LENGTH is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    QDGRID_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    QDGRID_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LTYPE is a String of width 35.
      Documented as an Enumerated_Domain
      There are 4 distinct values.
      3 values occur more than once in the data.
    TICS is a String of width 4.
      Documented as an Enumerated_Domain
      There are 3 distinct values.
      3 values occur more than once in the data.
    Attribute file sf-ipys.dbf
      Number of fields: 9
      Number of records: 240
    AREA is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    PERIMETER is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    QDGRID_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    QDGRID_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    NAME is a String of width 35.
      Documented as an Enumerated_Domain
      There are 197 distinct values.
      1 values occur more than once in the data.
    SHEET is a String of width 35.
      Documented as an Enumerated_Domain
      There are 13 distinct values.
      12 values occur more than once in the data.
    COMPIL is a String of width 7.
      Documented as an Enumerated_Domain
      There are 27 distinct values.
      15 values occur more than once in the data.
    PERCENT is an Integer of width 3.
      0 negative, 10 positive, 1 zero values
      Documented as Enumerated_Domain
      10 values occur more than once in the data.
    SCALE is an Integer of width 4.
      0 negative, 2 positive, 1 zero values
      Documented as Enumerated_Domain
      3 values occur more than once in the data.
    Attribute file sf-lpys.dbf
      Number of fields: 25
      Number of records: 6
    AREA is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    PERIMETER is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    EFLPPYS_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    EFLPPYS_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    STA is a String of width 5.
      Documented as an Enumerated_Domain
      There are 6 distinct values.
      Each value occurs only once in the data.
    EQK is a String of width 10.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "1989".
    SRC is a String of width 30.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "Tinsley and others, 1998".
    KIND is a String of width 12.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "area".
    ACC is a String of width 5.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "P".
    EXT is a String of width 10.
      Documented as an Enumerated_Domain
      For all records in the file this field is empty.
    COMM is a String of width 50.
      Documented as an Enumerated_Domain
      All records have the same value for this field.
      The value is "bndy drawn around dot pattern on source map".
    FIELD is a String of width 50.
      Documented as an Enumerated_Domain
      There are 6 distinct values.
      Each value occurs only once in the data.
    LS_H is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    LS_S is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    LATSP is an Integer of width 2.
      0 negative, 1 positive, 0 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    SETL is an Integer of width 2.
      0 negative, 1 positive, 0 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    CRK_ST is an Integer of width 2.
      0 negative, 1 positive, 0 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    CRK_GND is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    PIPE is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    BOIL is an Integer of width 2.
      0 negative, 1 positive, 0 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    WELL is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    MISC is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    ABS is an Integer of width 2.
      0 negative, 0 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    EFFECTS is a String of width 35.
      Documented as an Enumerated_Domain
      There are 2 distinct values.
      2 values occur more than once in the data.
    SF is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      1 values occur more than once in the data.
    Attribute file sf-qlns.dbf
      Number of fields: 8
      Number of records: 30849
    FNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    TNODE_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    RPOLY_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LENGTH is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    QUAT_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    QUAT_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    LTYPE is a String of width 35.
      Documented as an Enumerated_Domain
      There are 8 distinct values.
      8 values occur more than once in the data.
    Attribute file sf-qpys.dbf
      Number of fields: 7
      Number of records: 13827
    AREA is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    PERIMETER is a Double of width 13 and precision 3.
      Intrinsic to ArcInfo, not documented here.
    QUAT_ is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    QUAT_ID is an Integer of width 11.
      Intrinsic to ArcInfo, not documented here.
    PTYPE is a String of width 35.
      Documented as an Enumerated_Domain
      There are 68 distinct values.
      64 values occur more than once in the data.
    LIQ is a String of width 8.
      Documented as an Enumerated_Domain
      There are 8 distinct values.
      8 values occur more than once in the data.
    LIQ_SOURCE is an Integer of width 2.
      0 negative, 1 positive, 1 zero values
      Documented as Enumerated_Domain
      2 values occur more than once in the data.
    
    Entity_and_Attribute_Detail_Citation: http://pubs.usgs.gov/of/2000/of00-444/of00-444_1a.txt

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Knudsen, K.L.
    • Sowers, J.M.
    • Witter, R.C.
    • Wentworth, C.M.
    • Helley, E.J.
    • Nicholson, R.S.
    • Wright, H.M.
    • Brown, K.M.
  2. Who also contributed to the data set?
    Geology by Keith L. Knudsen, Janet M. Sowers, Robert C. Witter, Carl M. Wentworth and Edward J. Helley. Digital database by Carl M. Wentworth, Robert S. Nicholson, Heather M. Wright, and Katherine M. Brown
  3. To whom should users address questions about the data?
    USGS Earthquake Hazards Team
    Attn: Steve Walter
    345 Middlefield Road, MS 977
    Menlo Park, CA
    USA


Why was the data set created?

Map delineation of the different types and ages of Quaternary deposits supports evaluation of susceptibility to liquefaction, the immediate application of the work, but serves many other purposes as well. It provides a framework for interpreting the architecture and history of the Quaternary sedimentary basins, which is used in estimating earthquake shaking and modeling the groundwater system. The mapping is also useful in constraining the ages and histories of offsetting faults, in guiding geotechnical investigations, and in other engineering, geologic, and archeological applications.

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: 1999 (process 1 of 2)
    The Quaternary deposits database was compiled digitally in vector form in ARC/INFO as individual 7.5-minute (126) and 0. 5x1.0-degree (2) quadrangles at scales of 1:24,000 and 1:100,000, respectively. The 1:100,000 materials were modified from previously released spatial databases for the San Francisco and Napa 0.5x1.0-degree quadrangles (Knudsen and others, 1997, and Sowers and others, 1998, respectively), and the 1:24,000 materials were variously modified from previous work or newly digitized, depending on the degree of remapping involved (see part 3, Description of Mapping). These many individual pieces were converted to UTM projection and assembled into a single regional layer. Remaining quadrangle boundary problems were resolved where possible, although some remain where the status of mapping differs across the boundary. The resulting spatial database retains the resolution of the input parts, some at 1:24,000, some at 1:100,000. Much of the fine detail in the spatial database is too small for legible portrayal at the regional scale of the colored maps (1:275,000).
    The ground-effects database was compiled digitally in vector form from 1:100,000 and 1:24,000 materials, including relocation at 1:24,000 of 1:250,000-scale map features based on text descriptions of historic effects (see Appendix C of part 3, Description of Mapping). The Loma Prieta dataset was digitized directly in ARC/INFO, whereas the historic dataset was digitized in MapInfo and subsequently converted to ARC/ INFO. Points and lines for the historic and Loma Prieta datasets were combined into a single vector layer, but the polygons could not be (some polygons overlap), and these remain separate.
    The vector lines in the quadrangle database were generated automatically with high precision in ARC/INFO as a latitude/ longitude grid, densified to a vertex spacing of 0.005 degrees along all the lines, and reprojected to UTM .
    The ARC layers (coverages) are stored in UTM projection, but the shape files are in decimal degrees of longitude and latitude, prepared by projecting and converting the primary UTM coverages.
    Digital compilation of the many 7.5-minute quadrangles involved was carried out over a period of several years, during which one or more quadrangles each were digitized by Andrew Barron, Gregg Beukelman, Joe Colgan, Jennifer Davis, Scott Graham, Marjorie Lucks, Tom May, David Ramsey, Carrie Randolph, Joel Robinson, Adam Soule, and Jim Thordsen. Digital compilation of the 0.5° x 1° quadrangles was done separately for the reports by Knudsen and others (1997) and Sowers and others (1998).
    Date: 26-Jan-2001 (process 2 of 2)
    Creation of original metadata record Person who carried out this activity:
    C.M. Wentworth
    U.S. Geological Survey
    345 Middlefield Rd., MS 977
    Menlo Park, CA
    USA

  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?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
    The report describes the Quaternary geology of the map area at 1:24,000 - 1:100,000 scale; map graphics at 1:275,000 scale. See Open-File pamphlet of00-444_1x.
  5. How consistent are the relationships among the observations, including topology?
    Polygon and chain-node topology 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:
Use is limited by the 1:24,000 - 1:100,000 scale spatial resolution of the data.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey
    345 Middlefield Road
    Menlo Park, CA
    USA

  2. What's the catalog number I need to order this data set? USGS Open-File Report 00-444
  3. What legal disclaimers am I supposed to read?
    This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. 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?
    • Availability in digital form:
      Data format: 4 PostScript plotfiles, one each for the Quaternary geology map, the liquefaction map, the Open-File pamphlet, and the Description of Mapping. in format PostScript (EPSF) (version 2.0 (EPSF-1.2)) PostScript files generated by Arc/Info 8.0 Size: 11.6
      Network links: http://pubs.usgs.gov/of/2000/of00-444/of00-444_10a.tar.gz
      Data format: 4 PDF (Adobe Acrobat) plotfiles, one each for the Quaternary geology map, the liquefaction map, the Open-File pamphlet, and the Description of Mapping. in format PDF (version 1.3) PDF created by Acrobat Distiller 4.0 for Windows from PostScript files generated by Arc/Info 8.0 Size: 11.2
      Network links: http://pubs.usgs.gov/of/2000/of00-444/of00-444_10b.tar
      Data format: 18 Arc/Info export (.e00) files, along with supporting pamphlet plotfiles, revisions list, and import AML. See the Open-File pamphlet (of00-444_1a.txt) for more information about the content of the digital database. in format ARCE (version 7.2.1) Size: 1.3
      Network links: http://pubs.usgs.gov/of/2000/of00-444/of00-444_9a.tar.gz
      Data format: 18 ArcView shape files, along with supporting pamphlet plotfiles, and revisions list. See the Open-File pamphlet (of00-444_1a.txt) for more information about the content of the digital database. in format Shapefile (version 1.0) Size: 21.5
      Network links: http://pubs.usgs.gov/of/2000/of00-444/of00-444_9b.tar.gz
    • Cost to order the data: none


Who wrote the metadata?

Dates:
Last modified: 13-Jun-2016
Metadata author:
Peter N Schweitzer
USGS Midwest Area
Collection manager, USGS Geoscience Data Clearinghouse, http://geo-nsdi.er.usgs.gov/
Mail Stop 954
12201 Sunrise Valley Dr
Reston, VA
USA

703-648-6533 (voice)
703-648-6252 (FAX)
pschweitzer@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:

This page is <https://geo-nsdi.er.usgs.gov/metadata/open-file/00-444/metadata.faq.html>
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