Liquefaction Hazard Maps for Three Earthquake Scenarios for the Communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale: Northern Santa Clara County, California Metadata: * Identification_Information <#Identification_Information> * Data_Quality_Information <#Data_Quality_Information> * Spatial_Data_Organization_Information <#Spatial_Data_Organization_Information> * Spatial_Reference_Information <#Spatial_Reference_Information> * Entity_and_Attribute_Information <#Entity_and_Attribute_Information> * Distribution_Information <#158931456> * Metadata_Reference_Information <#Metadata_Reference_Information> ------------------------------------------------------------------------ /Identification_Information:/ /Citation:/ /Citation_Information:/ /Originator:/ Thomas L Holzer, Thomas E Noce, Michael J Bennett /Publication_Date:/ 9/12/2008 /Title:/ Liquefaction Hazard Maps for Three Earthquake Scenarios for the Communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale: Northern Santa Clara County, California /Edition:/ 1.0 /Geospatial_Data_Presentation_Form:/ maps and geospatial databases /Series_Information:/ /Series_Name:/ U.S. Geological Survey Open File Report /Issue_Identification:/ 2008-1270 /Publication_Information:/ /Publication_Place:/ Menlo Park, Calif. /Publisher:/ U.S. Geological Survey /Online_Linkage:/ http://pubs.usgs.gov/of/2008/1270/ /Description:/ /Abstract:/ Maps showing the probability of surface manifestations of liquefaction in the northern Santa Clara Valley were prepared with liquefaction probability curves. The area includes the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale. The probability curves were based on complementary cumulative frequency distributions of the liquefaction potential index (LPI) for surficial geologic units in the study area. LPI values were computed with extensive cone penetration test soundings. Maps were developed for three earthquake scenarios, an M7.8 on the San Andreas Fault comparable to the 1906 event, an M6.7 on the Hayward Fault comparable to the 1868 event, and an M6.9 on the Calaveras Fault. Ground motions were estimated with the Boore and Atkinson (2008) attenuation relation. Liquefaction is predicted for all three events in young Holocene levee deposits along the major creeks. Liquefaction probabilities are highest for the M7.8 earthquake, ranging from 0.33 to 0.37 if a 1.5-m deep water table is assumed, and 0.10 to 0.14 if a 5-m deep water table is assumed. Liquefaction probabilities of the other surficial geologic units are less than 0.05. Probabilities for the scenario earthquakes are generally consistent with observations during historical earthquakes. /Purpose:/ This report contains prototype liquefaction hazard maps. The purpose of this report is to illustrate the use of the liquefaction potential index for probabilistic liquefaction hazard 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 maps, geospatial data files, and text files of liquefaction hazard for the Northern portion of Santa Clara County. This report consists of (1) 12 shapefiles consisting of geology, faults, streets, highways, liquefaction probabilities, water bodies, and study area boundaries, and the associated layer files; (2) 3 small-scale colored maps of liquefaction probability), (3) the report text describing the methodologies used to determine liquefaction potential and to produce the liquefaction probability maps, and (4) the database description pamphlet (this document). See the revision list (of2008-1270_version_history.txt) or Open File report technical report (of2008-1270_technical_report.pdf) for further details. /Time_Period_of_Content:/ /Time_Period_Information:/ /Single_Date/Time:/ /Calendar_Date:/ 9/12/2008 /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:/ -122.206 /East_Bounding_Coordinate:/ -121.746 /North_Bounding_Coordinate:/ 37.487943 /South_Bounding_Coordinate:/ 37.246723 /Keywords:/ /Theme:/ /Theme_Keyword_Thesaurus:/ ISO 19115 Topic Categories /Theme_Keyword:/ Hazard Maps /Theme_Keyword:/ Probability /Theme_Keyword:/ LPI /Theme_Keyword:/ Digital database /Theme_Keyword:/ Geodatabase /Theme_Keyword:/ Liquefaction /Theme_Keyword:/ Earthquake /Place:/ /Place_Keyword_Thesaurus:/ GeoscientificInformation /Place_Keyword:/ San Jose /Place_Keyword:/ Campbell /Place_Keyword:/ Cupertino /Place_Keyword:/ Los Altos /Place_Keyword:/ Los Gatos /Place_Keyword:/ Milpitas /Place_Keyword:/ Mountain View /Place_Keyword:/ Palo Alto /Place_Keyword:/ Santa Clara /Place_Keyword:/ Saratoga /Place_Keyword:/ Sunnyvale /Place_Keyword:/ Santa Clara County /Place_Keyword:/ California /Place_Keyword:/ San Francisco Bay Area /Place_Keyword:/ USA /Stratum:/ /Stratum_Keyword:/ Levee deposits /Stratum_Keyword:/ Alluvial fan deposits /Stratum_Keyword:/ Channel deposits /Stratum_Keyword:/ Point bar deposits /Stratum_Keyword:/ Estuarine deposits /Temporal:/ /Temporal_Keyword:/ Holocene /Temporal_Keyword:/ Paleocene /Temporal_Keyword:/ Pleistocene /Temporal_Keyword:/ Quaternary /Access_Constraints:/ None /Use_Constraints:/ Use is limited by the 1:24,000 scale spatial resolution of the data. These data were created for the sole purpose of the Northern Santa Clara County liquefaction hazard study. The United States Geological Survey makes no expressed or implied warranty regarding the accuracy of these data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data on any other system. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. /Point_of_Contact:/ /Contact_Information:/ /Contact_Person_Primary:/ /Contact_Person:/ Thomas L Holzer /Contact_Organization:/ U.S. Geological Survey, Earthquake Hazards Team /Contact_Position:/ Geologist /Contact_Address:/ /Address_Type:/ mailing and physical address /Address:/ 345 Middlefield Rd MS 977 /City:/ Menlo Park /State_or_Province:/ CA /Postal_Code:/ 94025 /Country:/ USA /Contact_Electronic_Mail_Address:/ tholzer@usgs.gov /Data_Set_Credit:/ Liquefaction hazard probability scenarios by Thomas L. Holzer, Thomas E. Noce, and Michael J. Bennett Digital database by Thomas E Noce /Security_Information:/ /Security_Classification_System:/ none /Security_Classification:/ Unclassified /Security_Handling_Description:/ None /Native_Data_Set_Environment:/ Solaris 6 and 7, UNIX, Windows XP, Microsoft Word, Microsoft Excel, Acrobat Distiller, ARCMap version 9.x ------------------------------------------------------------------------ /Data_Quality_Information:/ /Attribute_Accuracy:/ /Attribute_Accuracy_Report:/ See Entity_Attribute_Information /Quantitative_Attribute_Accuracy_Assessment:/ /Attribute_Accuracy_Value:/ See explanation /Attribute_Accuracy_Explanation:/ Attribute accuracy is described, where present, with each attribute defined in the Entity and Attribute Section. /Logical_Consistency_Report:/ Polygon and chain-node topology present /Completeness_Report:/ The report describes the liquefaction probability of the map area at 1:24,000 scale; map graphics at 1:100,000 scale. See of2008-1270_technical_report.pdf ------------------------------------------------------------------------ /Spatial_Data_Organization_Information:/ /Direct_Spatial_Reference_Method:/ Vector ------------------------------------------------------------------------ /Spatial_Reference_Information:/ /Horizontal_Coordinate_System_Definition:/ /Planar:/ /Grid_Coordinate_System:/ /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_Coordinate_Information:/ /Planar_Coordinate_Encoding_Method:/ coordinate pair /Coordinate_Representation:/ /Abscissa_Resolution:/ 1.0 /Ordinate_Resolution:/ 1.0 /Planar_Distance_Units:/ meters /Geodetic_Model:/ /Horizontal_Datum_Name:/ North American Datum of 1927 /Ellipsoid_Name:/ Clarke 1866 /Semi-major_Axis:/ 6378206.4 /Denominator_of_Flattening_Ratio:/ 294.98 ------------------------------------------------------------------------ /Entity_and_Attribute_Information:/ /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Liquefaction_probability /Entity_Type_Definition:/ Probability of liquefaction /Attribute:/ /Attribute_Domain_Values:/ /Enumerated_Domain:/ /Enumerated_Domain_Value:/ 30 to 40% /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Enumerated_Domain_Value_Definition_Source:/ Liquefaction probabilities for all three scenarios were calculated in Arc ModelBuilder at nodes in a 50m grid with liquefaction probability curves appropriate to the geology at the node. See of2008-1270_technical_report.pdf for details. The resulting 50m probability grids were converted to polygons and clipped to fit the boundaries of the geologic units and the study area. Each of the three scenarios (for San Andreas, Hayward, and Calaveras earthquakes) share this common methodology and definition in this database. /Enumerated_Domain:/ /Enumerated_Domain_Value:/ 20 to 30% /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Enumerated_Domain:/ /Enumerated_Domain_Value:/ 10 to 20% /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Enumerated_Domain:/ /Enumerated_Domain_Value:/ 5 to 10% /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Enumerated_Domain:/ /Enumerated_Domain_Value:/ 0 to 5% /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Enumerated_Domain:/ /Enumerated_Domain_Value:/ Not assigned /Enumerated_Domain_Value_Definition:/ Probability of liquefaction or percent of the area predicted to liquefy /Attribute_Value_Accuracy_Information:/ /Attribute_Value_Accuracy:/ 5% /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Bedrock /Entity_Type_Definition:/ Geologic unit label /Attribute:/ /Attribute_Domain_Values:/ /Enumerated_Domain:/ /Enumerated_Domain_Value:/ br /Enumerated_Domain_Value_Definition:/ Areas of surficial bedrock /Enumerated_Domain_Value_Definition_Source:/ The bedrock was originally published in Witter, R.C., Knudsen, K.L., Sowers, J.M., Wentworth, C.M., Koehler, R.D., and Randolph, C.E., 2006, Maps of Quaternary deposits and liquefaction susceptibility in the central San Francisco Bay region, California: U.S. Geological Survey Open-file Report 06-1037, http://pubs.usgs.gov/of/2006/1037/of06-1037. It was extracted and dissolved for use in this publication. /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Calveras_Fault /Entity_Type_Definition:/ Fault /Attribute:/ /Attribute_Definition_Source:/ This file represents the northern and central segments of the Calaveras Fault as described in: WGCEP, 2003, Earthquake probabilities in the San Francisco Bay region 2002-2032: U.S. Geological Survey Open-file Report 03-214, http://pubs.usgs.gov/of/2003/of03-214/. /Attribute_Domain_Values:/ /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Hayward_Fault /Entity_Type_Definition:/ Fault /Attribute:/ /Attribute_Definition_Source:/ This file represents the Hayward Fault as described in: WGCEP, 2003, Earthquake probabilities in the San Francisco Bay region 2002-2032: U.S. Geological Survey Open-file Report 03-214, http://pubs.usgs.gov/of/2003/of03-214/. /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ San_Andreas_Fault /Entity_Type_Definition:/ Fault /Entity_Type_Definition_Source:/ This file represents the segments of the San Andreas Fault as described in: WGCEP, 2003, Earthquake probabilities in the San Francisco Bay region 2002-2032: U.S. Geological Survey Open-file Report 03-214, http://pubs.usgs.gov/of/2003/of03-214/. /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Major_Highways /Entity_Type_Definition:/ Interstate highways /Entity_Type_Definition_Source:/ ESRI Street Map (2001 edition) /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Streets /Entity_Type_Definition:/ Local streets /Entity_Type_Definition_Source:/ ESRI Street Map (2001 edition) /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Study_Area /Entity_Type_Definition:/ Boundary of study area /Entity_Type_Definition_Source:/ Extracted from ESRI Street Map (2001 edition) for the portion of the Santa Clara County boundary that coincides with the northern and western margin of the study area, and hand digitized along the southern and eastern margins of the study area /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Water /Entity_Type_Definition:/ Bodies of water contained within the study area /Entity_Type_Definition_Source:/ Originally published in Witter, R.C., Knudsen, K.L., Sowers, J.M., Wentworth, C.M., Koehler, R.D., and Randolph, C.E., 2006, Maps of Quaternary deposits and liquefaction susceptibility in the central San Francisco Bay region, California: U.S. Geological Survey Open-file Report 06-1037, http://pubs.usgs.gov/of/2006/1037/of06-1037. Subsequently dissolved and simplified for the purposes of this publication. /Attribute:/ /Attribute_Domain_Values:/ /Enumerated_Domain:/ /Enumerated_Domain_Value:/ H2O /Enumerated_Domain_Value_Definition:/ Water /Detailed_Description:/ /Entity_Type:/ /Entity_Type_Label:/ Not_studied /Entity_Type_Definition:/ Areas excluded from liquefaction study within the study area /Entity_Type_Definition_Source:/ Original extracted from Witter, R.C., Knudsen, K.L., Sowers, J.M., Wentworth, C.M., Koehler, R.D., and Randolph, C.E., 2006, Maps of Quaternary deposits and liquefaction susceptibility in the central San Francisco Bay region, California: U.S. Geological Survey Open-file Report 06-1037, http://pubs.usgs.gov/of/2006/1037/of06-1037. Subsequently dissolved and simplified for this publication. /Attribute:/ /Attribute_Domain_Values:/ /Enumerated_Domain:/ /Enumerated_Domain_Value:/ ns /Enumerated_Domain_Value_Definition:/ not studied /Overview_Description:/ /Entity_and_Attribute_Overview:/ The databases in this report were compiled in ARCMap, a commercial Geographic Information System (Environmental Systems Research Institute, Redlands, California). All of the attributes in the various attribute tables of the feature classes and shapefiles included in the report are set or calculated by ArcMap. /Entity_and_Attribute_Detail_Citation:/ This report combined with the explanatory readme file and Technical Report: of2008-1270_readme.txt and of2008-1270_technical_report.pdf. ------------------------------------------------------------------------ /Distribution_Information:/ /Distributor:/ /Contact_Information:/ /Contact_Address:/ /Address:/ http://pubs.usgs.gov/of/2008/1270/ /Contact Instructions:/ Please contact through http://pubs.usgs.gov/of/2008/1270/ ------------------------------------------------------------------------ /Metadata_Reference_Information:/ /Metadata_Date:/ 20080825 /Metadata_Contact:/ /Contact_Information:/ /Contact_Person_Primary:/ /Contact_Person:/ Thomas L. Holzer /Contact_Organization:/ U.S.Geological Survey /Contact_Position:/ Geologist /Contact_Address:/ /Address_Type:/ mailing address /Address:/ 345 Middlefield Rd MS 977 /City:/ Menlo Park /State_or_Province:/ CA /Postal_Code:/ 94025 /Country:/ USA /Contact_Electronic_Mail_Address:/ tholzer@usgs.gov /Metadata_Standard_Name:/ FGDC Content Standards for Digital Geospatial Metadata /Metadata_Time_Convention:/ local time /Metadata_Access_Constraints:/ None /Metadata_Use_Constraints:/ None /Metadata_Security_Information:/ /Metadata_Security_Classification:/ Unclassified /Metadata_Extensions:/ /Online_Linkage:/ of2008-1270_metadata.txt