Citation:
Citation_Information:
Originator: Knudsen, K.L.
Originator: Sowers, J.M.
Originator: Witter, R.C.
Originator: Wentworth, C.M.
Originator: Helley, E.J.
Originator: Nicholson, R.S.
Originator: Wright, H.M.
Originator: Brown, K.M.
Publication_Date: 2000
Title:
Preliminary maps of Quaternary deposits and liquefaction
susceptibility, nine-county San Francisco Bay region,
California: a digital database
Edition: 1.0
Geospatial_Data_Presentation_Form: maps and spatial databases
Series_Information:
Series_Name: U.S. Geological Survey Open-File Report
Issue_Identification: 00-444
Publication_Information:
Publication_Place: Menlo Park, CA
Publisher: U.S. Geological Survey
Online_Linkage: http://pubs.usgs.gov/of/2000/of00-444/
Description:
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.
Purpose:
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.
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.
Data_Set_Structure:
Data_Set_Part:
Part_Name: of00-444_9a.tar.gz
Part_Type: Database package for Arc/Info users
Part_Description:
Data arranged for use with Arc/Info or other software
capable of reading the ESRI export format (.e00). Geographic
features are projected using UTM zone 10, with datum NAD27.
Data_Set_Part:
Part_Name: sf-quat
Part_Type: Arc/Info coverage
Part_Description: Quaternary Map (stored in export file of00-444_4a.e00)
Data_Set_Part:
Part_Name: sf-qanno
Part_Type: Arc/Info coverage
Part_Description: Annotation (stored in export file of00-444_4b.e00)
Data_Set_Part:
Part_Name: sf-effects
Part_Type: Arc/Info coverage
Part_Description: Effects points/lines (stored in export file of00-444_5a1.e00)
Data_Set_Part:
Part_Name: sf-efhspys
Part_Type: Arc/Info coverage
Part_Description: Historic polygons (stored in export file of00-444_5a2.e00)
Data_Set_Part:
Part_Name: sf-eflppys
Part_Type: Arc/Info coverage
Part_Description: Loma Prieta polygons (stored in export file of00-444_5a3.e00)
Data_Set_Part:
Part_Name: sf-eanno
Part_Type: Arc/Info coverage
Part_Description: Effects Annotation (stored in export file of00-444_5a4.e00)
Data_Set_Part:
Part_Name: sf-qdgrid
Part_Type: Arc/Info coverage
Part_Description: Quad Index (stored in export file of00-444_6a.e00)
Data_Set_Part:
Part_Name: of00-444_9b.tar.gz
Part_Type: Database package for ArcView users
Part_Description:
Data arranged for use with ArcView or other software
capable of reading the ESRI shapefile format. Geographic
features are expressed in latitude and longitude.
Data_Set_Part:
Part_Name: sf-elns
Part_Type: ArcView shapefile
Part_Description: Ground effects (line features)
Data_Set_Part:
Part_Name: sf-epts
Part_Type: ArcView shapefile
Part_Description: Ground effects (point features)
Data_Set_Part:
Part_Name: sf-hpys
Part_Type: ArcView shapefile
Part_Description: Ground effects (polygon featues)
Data_Set_Part:
Part_Name: sf-ipys
Part_Type: ArcView shapefile
Part_Description: 1:24k quadrangles as polygons
Data_Set_Part:
Part_Name: sf-ilns
Part_Type: ArcView shapefile
Part_Description: 1:24k quadrangle boundaries as lines
Data_Set_Part:
Part_Name: sf-qlns
Part_Type: ArcView shapefile
Part_Description: Line features of quaternary geology
Data_Set_Part:
Part_Name: sf-qpys
Part_Type: ArcView shapefile
Part_Description: Polygonal features of quaternary geology
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20001201
Currentness_Reference:
The date given is the publication date. The information in the report was current at the time of publication.
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -121.125
East_Bounding_Coordinate: -123.625
North_Bounding_Coordinate: 38.866667
South_Bounding_Coordinate: 36.866667
Keywords:
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: Quaternary
Theme_Keyword: surficial geologic units
Theme_Keyword: liquefaction
Theme_Keyword: engineering geology
Theme_Keyword: earthquake preparedness
Theme_Keyword: geospatial datasets
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: Quaternary surficial deposits
Theme_Keyword: Liquefaction susceptibility
Theme_Keyword: Liquefaction
Theme_Keyword: Earthquake ground effects
Theme_Keyword: Earthquake ground failures
Theme_Keyword: Digital spatial database
Theme_Keyword: Vector data
Theme_Keyword: Soils
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: geoscientificInformation
Place:
Place_Keyword_Thesaurus: none
Place_Keyword: United States of America
Place_Keyword: California
Place_Keyword: Solano County
Place_Keyword: San Francisco County
Place_Keyword: Sonoma County
Place_Keyword: Marin County
Place_Keyword: Napa County
Place_Keyword: Contra Costa County
Place_Keyword: Alameda County
Place_Keyword: San Mateo County
Place_Keyword: Santa Clara County
Place_Keyword: San Francisco Bay Region
Place_Keyword: San Francisco Bay Area
Place:
Place_Keyword_Thesaurus: Augmented FIPS 10-4 and FIPS 6-4
Place_Keyword: f06001 = Alameda
Place_Keyword: f06013 = Contra Costa
Place_Keyword: f06095 = Solano
Place_Keyword: f06075 = San Francisco
Place_Keyword: f06097 = Sonoma
Place_Keyword: f06041 = Marin
Place_Keyword: f06055 = Napa
Place_Keyword: f06081 = San Mateo
Place_Keyword: f06085 = Santa Clara
Stratum:
Stratum_Keyword_Thesaurus: ARC/INFO file SF_QUAT.UN
Stratum_Keyword: Artificial fill
Stratum_Keyword: Artificial fill over San Francisco Bay Mud
Stratum_Keyword: Dredge spoils
Stratum_Keyword: Gravel quarry
Stratum_Keyword: Artificial stream channel
Stratum_Keyword: Modern stream channel deposits
Stratum_Keyword: Alluvial fan deposits
Stratum_Keyword: Alluvial fan levee deposits
Stratum_Keyword: Stream terrace deposits
Stratum_Keyword: Alluvial deposits
Stratum_Keyword: Alluvial floodplain deposits
Stratum_Keyword: Flood basin deposits
Stratum_Keyword: Dune sand
Stratum_Keyword: Beach sand
Stratum_Keyword: San Francisco Bay Mud
Stratum_Keyword: Basin deposits
Stratum_Keyword: Alluvial fan-estuarine complex deposits
Stratum_Keyword: Alluvial fan deposits, fine facies
Stratum_Keyword: Alluvium, undifferentiated
Stratum_Keyword: Marine terrace deposits
Stratum_Keyword: Pediment deposits
Stratum_Keyword: Bedrock
Temporal:
Temporal_Keyword_Thesaurus: None
Temporal_Keyword: Quaternary
Temporal_Keyword: Pleistocene
Temporal_Keyword: Holocene
Access_Constraints: None
Use_Constraints:
Use is limited by the 1:24,000 - 1:100,000 scale spatial resolution of the data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USGS Earthquake Hazards Team
Contact_Person: Steve Walter
Contact_Address:
Address_Type: mailing address
Address: 345 Middlefield Road, MS 977
City: Menlo Park
State_or_Province: CA
Postal_Code: 94025
Country: USA
Browse_Graphic:
Browse_Graphic:
Data_Set_Credit:
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
Native_Data_Set_Environment:
Solaris 6 and 7, UNIX, Microsoft Word, Microsoft Excel, Acrobat Distiller, ARC/INFO version 7.x, UNIX texteditor