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This data set is a series of polylines denoting fault lines mapped in USGS Publication MF-1790, "Geologic Map of the Late Cenozoic Deposits of the Sacramento Valley and Northern Sierran Foothills, California" (Helley and Harwood,1985). This data set was created by scanning the five- original sheets from USGS Publication MF-1790 (Helley and Harwood, 1985), the five sheets were georeferenced individually and the geologic information was digitized using AutoCAD 2006. The accuracy of the digitized lines was deemed to be within acceptable error tolerances, with the digitized lines accurately matching the original drafted lines in USGS Publication MF-1790 (Helley and Harwood, 1985). In general, the width of the contact lines on the paper copy, accounting for scale, ranged up to about 20 meters (66 feet). During the original digitization, minor topological mistakes (such as identical rock units on both sides of a lithologic contact or unclosed polygons) and omissions (such as unidentified lithologic units) were applied according to the best available knowledge. Comparisons were made between the original mylar and colorized field sheets (as available), in addition to the Geologic Map of the Battle Creek Fault Zone, Northern Sacramento Valley, California (USGS Map MF-1298, 1981), the Geologic Map of the Chico Monocline and Northeastern Part of the Sacramento Valley, California (USGS Miscellaneous Investigations Series Map I-1238, 1981), and the Geologic Map of the Red Bluff 30' X 60' Quadrangle, California (USGS Geologic Investigation Series Map I-2542, 1995). The correlation and description of geologic units were excerpted from USGS Publication MF-1790m (Helley and Harwood, 1985).

This data set is a series of polylines denoting fault lines mapped in USGS Publication MF-1790, "Geologic Map of the Late Cenozoic Deposits of the Sacramento Valley and Northern Sierran Foothills, California" (Helley and Harwood,1985). This data set was created by scanning the five- original sheets from USGS Publication MF-1790 (Helley and Harwood, 1985), the five sheets were georeferenced individually and the geologic information was digitized using AutoCAD 2006. The accuracy of the digitized lines was deemed to be within acceptable error tolerances, with the digitized lines accurately matching the original drafted lines in USGS Publication MF-1790 (Helley and Harwood, 1985). In general, the width of the contact lines on the paper copy, accounting for scale, ranged up to about 20 meters (66 feet). During the original digitization, minor topological mistakes (such as identical rock units on both sides of a lithologic contact or unclosed polygons) and omissions (such as unidentified lithologic units) were applied according to the best available knowledge. Comparisons were made between the original mylar and colorized field sheets (as available), in addition to the Geologic Map of the Battle Creek Fault Zone, Northern Sacramento Valley, California (USGS Map MF-1298, 1981), the Geologic Map of the Chico Monocline and Northeastern Part of the Sacramento Valley, California (USGS Miscellaneous Investigations Series Map I-1238, 1981), and the Geologic Map of the Red Bluff 30' X 60' Quadrangle, California (USGS Geologic Investigation Series Map I-2542, 1995). The correlation and description of geologic units were excerpted from USGS Publication MF-1790m (Helley and Harwood, 1985).

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This data set contains the Alquist-Priolo Earthquake Fault Zones and fault traces as shown on the Official Alquist-Priolo Earthquake Fault Zones Map of the {quadName} quadrangle. The dataset is comprised of polygons that form regulatory zone boundaries (Alquist-Priolo Earthquake Fault Zones), lines that show identified fault traces, and label points and leaderlines for fault trace annotation. 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.

This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore San Francisco map area, California. The vector data file is included in "Faults_OffshoreSanFrancisco.zip," which is accessible from https://pubs.usgs.gov/ds/781/OffshoreSanFrancisco/data_catalog_OffshoreSanFrancisco.html. These data accompany the pamphlet and map sheets of Cochrane, G.R., Johnson, S.Y., Dartnell, P., Greene, H.G., Erdey, M.D., Golden, N.E., Hartwell, S.R., Endris, C.A., Manson, M.W., Sliter, R.W., Kvitek, R.G., Watt, J.T., Ross, S.L., and Bruns, T.R. (G.R. Cochrane and S.A. Cochran, eds.), 2015, California State Waters Map Series—Offshore of San Francisco, California (ver. 1.1, June 2015): U.S. Geological Survey Open-File Report 2015–1068, pamphlet 39 p., 10 sheets, scale 1:24,000, https://dx.doi.org/10.3133/ofr20151068. Faults in the Offshore of San Francisco map area are identified on seismic-reflection data based on abrupt truncation or warping of reflections and (or) juxtaposition of reflection panels with different seismic parameters such as reflection presence, amplitude, frequency, geometry, continuity, and vertical sequence. Faults were primarily mapped by interpretation of seismic reflection profile data (see field activities S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010.

This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore San Francisco map area, California. The vector data file is included in "Faults_OffshoreSanFrancisco.zip," which is accessible from https://pubs.usgs.gov/ds/781/OffshoreSanFrancisco/data_catalog_OffshoreSanFrancisco.html. These data accompany the pamphlet and map sheets of Cochrane, G.R., Johnson, S.Y., Dartnell, P., Greene, H.G., Erdey, M.D., Golden, N.E., Hartwell, S.R., Endris, C.A., Manson, M.W., Sliter, R.W., Kvitek, R.G., Watt, J.T., Ross, S.L., and Bruns, T.R. (G.R. Cochrane and S.A. Cochran, eds.), 2015, California State Waters Map Series—Offshore of San Francisco, California (ver. 1.1, June 2015): U.S. Geological Survey Open-File Report 2015–1068, pamphlet 39 p., 10 sheets, scale 1:24,000, https://dx.doi.org/10.3133/ofr20151068. Faults in the Offshore of San Francisco map area are identified on seismic-reflection data based on abrupt truncation or warping of reflections and (or) juxtaposition of reflection panels with different seismic parameters such as reflection presence, amplitude, frequency, geometry, continuity, and vertical sequence. Faults were primarily mapped by interpretation of seismic reflection profile data (see field activities S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010.

Data show fault-based seismic sources used in the time-independent component of the Uniform California Earthquake Rupture Forecast, Version 3 (UCERF3), which provides authoritative estimates of the magnitude, location, and time-averaged frequency of potentially damaging earthquakes in California. Fault model slip rates are given in millimeters per year. The shapefile depicts the surface traces of modeled faults, which are simplified from the CGS – USGS Quaternary Fault and Fold database (https://earthquake.usgs.gov/hazards/qfaults/). For modeled blind fault seismic sources, the traces represent the map-view fault tip projection of the subsurface fault. For additional information regarding modeled faults in UCERF3 please refer to Appendix A of the UCERF3 report (https://pubs.usgs.gov/of/2013/1165/). For additional information about UCERF3 please see http://www.conservation.ca.gov/cgs/rghm/psha/Pages/sr_228.aspx for the full UCERF3 publication and supporting products.