Webservice of Fault Traces Associated with Alquist-Priolo Fault Zones

Tags
Fault traces, faults, AP Zones


Summary

This data set contains the Alquist-Priolo Earthquake fault traces as shown on the Official Alquist-Priolo Earthquake Fault Zones Map of California. The dataset is comprised of lines that show identified fault traces.These features delineate areas where surface fault rupture previously has occurred, or where local topographic, geological, and geotechnical conditions indicate a potential for permanent ground displacements such that mitigation by avoidance as stated in Public Resources Code Section 2621.5 would be required.

Description

This map will assist cities and counties in fulfilling their responsibility to prohibit the location of developments and structures for human occupancy across the trace of active faults as required by the Alquist-Priolo Earthquake Fault Zoning Act (Public Resources Code, Division 2, Chapter 7.5, Sections 2621-2630). Local governments can withhold development permits until geologic investigations are conducted for specific sites and mitigation measures are incorporated into development plans. Sellers of property use the maps to check the location of their specific site and, if applicable, disclose to the buyer that the property lies within an earthquake fault zone as required by the Alquist-Priolo Earthquake Fault Zoning Act (PRC Section 2621.9). For information regarding the scope and recommended methods to be used in conducting the required site investigations, see California Geological Survey Special Publication 42, Fault-Rupture Hazard Zones in California.

Credits

Use limitations

LICENSE AGREEMENT: (c) 2018 California Department of Conservation, California Geological Survey. All rights reserved. No part of these data may be reproduced, transmitted, or distributed in any form or by any means, electronic or mechanical for any purpose, without the express written permission of the California Geological Survey except under the following conditions: 1) Personal use; 2) For publication in a report, in unmodified form, cite on figure or in text as "Reproduced with permission, California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones 2018"; and (3) for publication in a report in modified form; cite on figure or in text as "Modified from California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones, 2018.

Extent

West -124.215430   East -115.357743
North 41.999888   South 32.628487

Scale Range
Maximum (zoomed in) 1:5,000
Minimum (zoomed out) 1:150,000,000

ArcGIS Metadata 

Topics and Keywords 

*Content type  Downloadable Data
Export to FGDC CSDGM XML format as Resource Description No

Place keywords  City, County, California, USA

Theme keywords  Earthquake Fault Zone Map, earthquake hazard identification and mitigation, surface fault rupture, active fault, fault map, Alquist-Priolo

Citation 

Title Fault Traces
Alternate titles  GIS files of Official Maps of Alquist-Priolo Earthquake Fault Zones
Publication date 2017-06-28 00:00:00


Presentation formats* digital map


Series
Name Official Maps of Earthquake Fault Zones

Other citation details
Suggested_Citation: California Geological Survey. 2018, Official Maps of Earthquake Fault Zones: GIS files of Official Maps of Alquist-Priolo Earthquake Fault Zones of California, Sacramento, CA. Department of Conservation, California Geological Survey. http://maps.conservation.ca.gov/cgs/informationwarehouse/. Accessed {Day} {Month} {Year}



Citation Contacts 

Responsible party
Individual's name Senior Engineering Geologist, Earthquake Fault Zoning Unit
Organization's name California Geological Survey, Seismic Hazards Program
Contact's position Project Manager


Contact information
Phone
Voice (916) 322-1019
Fax (916) 445-3334

Address
Type
Delivery point 801 K Street, MS 12-31
City Sacramento
Administrative area California
Postal code 95814-3532
e-mail addressSHMP@conservation.ca.gov

Contact instructions
Online_Source: http://maps.conservation.ca.gov/cgs/informationwarehouse/



Resource Details 

Dataset languages* English (UNITED STATES)
Dataset character set  utf8 - 8 bit UCS Transfer Format


Spatial representation type* vector


Supplemental information
Supplemental_Information: Faults shown are the basis for establishing the boundaries of the Earthquake Fault Zones. This database may not show all faults that have the potential for surface fault rupture, either within the Earthquake Fault Zones or outside their boundaries.  The identification and location of these faults are based on the best available data. However, the quality of data used is varied. Fault traces have been drawn as accurately as possible at the map scale (1:24,000).

These data do not include Seismic Hazard Zones, if any, that may exist in this area. Please refer to the latest Official Maps of Seismic Hazard Zones for disclosures and other actions that are required by the Seismic Hazards Mapping Act. For more information on this subject see California Geological Survey Special Publication 117A.

Fault information on this map is not sufficient to serve as a substitute for the geologic site investigations required under Chapter 7.5 of Division 2 of the California Public Resources Code.

The original mapping was conducted on an earlier version of the USGS 7.5-minute topographic quadrangle map, utilizing California State Plane (Lambert Conformal Conic) projection (feet) and North American Datum of 1927. These data are currently maintained and distributed in a California Albers projection (meters) and North American Datum of 1983 [EPSG:3310]. It should be noted that the same geographic coordinate (e.g., -120.00 degrees longitude; 39.00 degrees latitude) will fall in a different location on the earth's surface when datums are changed.

*Processing environment  Version 6.2 (Build 9200) ; Esri ArcGIS 10.4.1.5686


ArcGIS item properties
*Name CGS_Work.CGSUSER.SHP_Fault_Traces_20170623
*Location Server=docsqlbiz; Service=sde:sqlserver:docsqlbiz; Database=CGS_Work; User=CGSuser; Version=sde.DEFAULT
*Access protocol ArcSDE Connection

Extents 

Extent
Geographic extent
Bounding rectangle
Extent type  Extent used for searching
*West longitude -124.215430
*East longitude -115.357743
*North latitude 41.999888
*South latitude 32.628487
*Extent contains the resource Yes

Extent in the item's coordinate system
*West longitude -13827598.384400
*East longitude -12841565.262200
*South latitude 3846094.955800
*North latitude 5160962.703200
*Extent contains the resource Yes

Resource Maintenance 

Resource maintenance
Update frequency  unknown


Resource Constraints 

Constraints
Limitations of use

LICENSE AGREEMENT: (c) 2018 California Department of Conservation, California Geological Survey. All rights reserved. No part of these data may be reproduced, transmitted, or distributed in any form or by any means, electronic or mechanical for any purpose, without the express written permission of the California Geological Survey except under the following conditions: 1) Personal use; 2) For publication in a report, in unmodified form, cite on figure or in text as "Reproduced with permission, California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones 2018"; and (3) for publication in a report in modified form; cite on figure or in text as "Modified from California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones, 2018.


Constraints
Limitations of use

Access_Constraints: Because digital data are easily altered, cities, counties, and others who use this file in their permit review and approval processes, or for other actions mandated by law (e.g., real estate disclosure at time of transfer) are advised to obtain the file directly from the Department of Conservation, California Geological Survey.


Constraints
Limitations of use

Distribution_Liability: These data are provided by the California Department of Conservation, California Geological Survey, as is. Any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the California Department of Conservation, California Geological Survey, or its associated contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) that arise in any way out of the use of these data and software, even if advised of the possibility of such damage.

The California Department of Conservation, California Geological Survey, makes no warranty, express or implied, regarding the data or its use. It is recommended that careful attention be paid to the contents of any metadata associated with a specific file, and that the originator of the data be contacted with any questions regarding appropriate use. The California Department of Conservation, California Geological Survey, shall not be held liable for improper or incorrect use of the data described and/or contained herein.


Constraints
Limitations of use

Fault traces shown on this map were interpreted at the time the Earthquake Fault Zones were prepared and may be superseded by newer fault maps.


Hide Resource Constraints ▲

Spatial Reference 

ArcGIS coordinate system
*Type Projected
*Geographic coordinate reference GCS_WGS_1984
*Projection WGS_1984_Web_Mercator_Auxiliary_Sphere
*Coordinate reference details
Projected coordinate system
Well-known identifier 102100
X origin -20037700
Y origin -30241100
XY scale 10000
Z origin 0
Z scale 1
M origin 0
M scale 1
XY tolerance 0.001
Z tolerance 2
M tolerance 2
High precision true
Latest well-known identifier 3857
Well-known text PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_Auxiliary_Sphere"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0],AUTHORITY["EPSG",3857]]

Reference system identifier
*Value 3857
*Codespace EPSG
*Version 8.8(9.3.1.2)


Hide Spatial Reference ▲

Spatial Data Properties 

Vector
*Level of topology for this dataset  geometry only


Geometric objects
Feature class name CGS_Work.CGSUSER.SHP_Fault_Traces_20170623
*Object type  composite
*Object count 35501



ArcGIS Feature Class Properties
Feature class name CGS_Work.CGSUSER.SHP_Fault_Traces_20170623
*Feature type Simple
*Geometry type Polyline
*Has topology FALSE
*Feature count 35501
*Spatial index TRUE
*Linear referencing FALSE



Hide Spatial Data Properties ▲

Data Quality 

Data quality report - Quantitative attribute accuracy
Measure description
Attribute_Accuracy_Report: Prior to 2016 digital GIS files delivered did not contain any entity attributes other than a unique identifier. As of 2016 the format of the digital GIS files has been changed and there are now four feature classes, each with associated attributes. For the most part, the attribute values were automatically generated and populated via Python scripts. The date values in FAULT_ZONE.RELEASED and FAULT_ZONE.PREV_DATES were verified against Table 3, Official Maps of Earthquake Fault Zones issues 1974 through August 2007, in Special Publication 42, Interim Revision 2007, Fault-Rupture Hazard Zones in California.  



Evaluation method
Quantitative_Attribute_Accuracy_Assessment:

   FAULT_TRACE—Geometry validation and topological checks were performed and duplicate trace segments and near-duplicate trace segments were deleted. Any multipart geometries were expanded into their respective components and kinks/kickbacks were corrected. This feature class contains occurrences of unbroken intersecting geometry, (i.e. fault traces that overlap but the overlapping traces do not share a vertex/node at the point of intersection), which have not been corrected.  





Data quality report - Completeness omission
Measure description
Completeness_Report: The dataset contains Alquist-Priolo Earthquake Fault Zones and faults as shown on the 2018 Official Map of Alquist-Priolo Earthquake Fault Zones for California. The topographic base map, which was included on the published map, is not included.





Data quality report - Absolute external positional accuracy
Measure description
Horizontal_Positional_Accuracy
Horizontal_Positional_Accuracy_Report: No systematic control surveys have been conducted to characterize the positional accuracy of the fault traces and earthquake fault zones. The mapping of fault traces and earthquake fault zone boundaries began in the early 1970’s and has continued into the present. The processes used to generate these data span a wide range of techniques from hand drawn maps on 7.5’ topographic sheets to heads up digitizing on LiDAR derived shaded relief base maps. The data have been interpreted and mapped as accurately as possible given the type of source data, and the time, staff and technology available at the time of mapping. More detailed information on mapping processes and base maps used may be available in the Fault Evaluation Report or for older maps, in the references used to compile the fault data.





Hide Data Quality ▲

Lineage 

Process step
Description
Process_Description: For maps released from 1974 – 1995 the following processes were completed to convert the clear film overlays into digital format.

 The original hardcopy maps (clear film overlays) used to reproduce Official Maps of Earthquake Fault Zones were the basis for developing the original GIS files. Each hardcopy map was scanned at full scale using an Anatech large-format scanner. The scanned image was translated to cit file format, geo-referenced (California State Plane Coordinate System (feet), North American Datum 1927), and digitized using Microstation v5.0 software to create vector files in dgn format. The digital files were printed at 1:24,000 scale and compared with the original clear-film overlay for completeness and accuracy. Digital files were then converted to dxf format, using individual layers to display specific line-styles as follows:

    Layer 1: Corner registration tics for individual quadrangle map and most text data
    Layer 3: Corner registration tics for oversized quadrangle maps (not present for most maps)
    Layer 7: EFZ boundary polygons
    Layer 8: Solid lines (accurately located fault traces)
    Layer 9: Long dashed lines (approximately located fault traces)
    Layer 10: Short-dashed lines (inferred fault traces)
    Layer 11: Dotted lines (concealed fault traces)
    Layer 12: Thin dashed and dotted lines (aerial photo lineament)





Process step
Description
Process_Description: In 2016 CGS updated the existing digital GIS data to meet the following goals: 1) a consistent projection and datum for all quadrangles, 2) uniform attribution, and 3) updated metadata. This process step included all GIS data released prior to July 1, 2016.
   
   Four ArcSDE feature classes and the necessary supporting domain tables were defined and created in an ArcGIS 10.3 enterprise geodatabase. The individual shapefiles for each quadrangle were then processed using Python scripts to 1) reproject from California State Plane Zone (feet), NAD 27 to California Albers (meters), NAD 83, 2) add attributes as needed depending on the target feature class, and 3) load the reprojected, attributed data into the appropriate ArcSDE enterprise feature class. Forty three of the 556 quadrangles were loaded using FME Workbench due to data that would not load via Python script or to deal with formatting differences.

   The data layers previously created were loaded to the four feature classes as follows:

    Layers 1&3    FAULT_LEADERLINE
    Layer 7     FAULT_ZONE
    Layers 8-12, polyline geometry  FAULT_TRACE
    Layers 8-12, text annotation  FAULT_LABEL
    
   Once loaded into the enterprise feature classes, QA/QC procedures were run to identify any geometry errors and standardize attributes. See Logical_Consistency_Report. For the FAULT_TRACES feature, the FAULT_NAME and FAULT_ZONE fields were updated by CGS staff by comparing the FAULT_TRACE faults with the CGS Quaternary Fault & Fold database. Where fault traces matched between the two databases, the fault name and fault zone name values from the Quaternary Fault & Fold database were copied to FAULT_TRACE features. Data values for FAULT_NAME and FAULT_ZONE were then updated to use proper case and faults previously named “unnamed” were updated to Null. In addition, inconsistent naming styles for some traces were standardized.
   
   When QA/QC and all updates were complete, Python scripts were used to extract the data from the enterprise ArcSDE feature classes by quad tile, generating potentially four shapefiles per quad. Metadata templates were created and Python scripts used to generate & customize the metadata for each quad. The updated GIS data and metadata for each quad were bundled and zipped via Python scripts and then posted to CGS’s Information Warehouse web site.





Hide Lineage ▲

Distribution 

Distribution format
*Name SDE Feature Class


Hide Distribution ▲

Fields 

Details for object Fault_Traces 
Field FAULT_NAME
 
Field description
Name of the fault



Field FAULT_ZONE
 
Field description
Name of the fault zone



Field LINE_TYPE
 
Field description
Description of the fault type
   Accurately Located
   Approximately Located
   Approximately Located, Queried
   Inferred
   Inferred, Queried
   Concealed
   Concealed, Queried
   Aerial Photo Lineament (generally not used after 1981)



Field LINE_STYLE
 
Field description
Description of the line style used for symbolizing the fault trace
   Solid Line (Accurately Located)
   Long Dashed (Approximately Located)
   Long Dashed with ? (Approximately Located, Queried)
   Short Dash (Inferred)
   Short Dashed with ? (Inferred, Queried)
   Dotted (Concealed)
   Dotted with ? (Concealed, Queried)
   Thin Dashed and Dotted (Aerial Photo Lineament; generally not used after 1981)



Field COMMENTS
 
Field description
Comments



Field QUAD_NAME
 
Field description
USGS 7.5 minute quadrangle official name





Hide Fields ▲

Metadata Details 

Metadata language English (UNITED STATES)
Metadata character set  utf8 - 8 bit UCS Transfer Format


Scope of the data described by the metadata  dataset
Scope name* dataset


*Last update 2017-06-28


ArcGIS metadata properties
Metadata format ArcGIS 1.0
Metadata style FGDC CSDGM Metadata
Standard or profile used to edit metadata FGDC


Created in ArcGIS for the item 2017-06-23 10:11:17
Last modified in ArcGIS for the item 2017-06-28 12:36:50


Automatic updates
Have been performed Yes
Last update 2017-06-28 09:25:51


Hide Metadata Details ▲

Metadata Maintenance 

Maintenance
Update frequency  unknown


Hide Metadata Maintenance ▲

Metadata Constraints 

Legal constraints
Other constraints
Access_Constraints: Because digital data are easily altered, cities, counties, and others who use this file in their permit review and approval processes, or for other actions mandated by law (e.g., real estate disclosure at time of transfer) are advised to obtain the file directly from the Department of Conservation, California Geological Survey. 

Other constraints
Use_Constraints: LICENSE AGREEMENT: (c) 2018 California Department of Conservation, California Geological Survey. All rights reserved. No part of these data may be reproduced, transmitted, or distributed in any form or by any means, electronic or mechanical for any purpose, without the express written permission of the California Geological Survey except under the following conditions: 1) Personal use; 2) For publication in a report, in unmodified form, cite on figure or in text as "Reproduced with permission, California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones, 2018"; and (3) for publication in a report in modified form; cite on figure or in text as "Modified from California Geological Survey, Official Map of Alquist-Priolo Earthquake Fault Zones, 2018

Hide Metadata Constraints ▲

FGDC Metadata (read-only) 

Entities and Attributes