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Journal Article

Detailed Mapping and Rupture Implications of the 1 km Releasing Bend in the Rodgers Creek Fault at Santa Rosa, Northern California

S. Hecker, V. E. Langenheim, R. A. Williams, C. S. Hitchcock, S. B. DeLong
Published: 01 March 2016
Bulletin of the Seismological Society of America (2016) 106 (2): 575–594.
DOI: https://doi.org/10.1785/0120150152
...S. Hecker; V. E. Langenheim; R. A. Williams; C. S. Hitchcock; S. B. DeLong Abstract Airborne light detection and ranging (lidar) topography reveals for the first time the trace of the Rodgers Creek fault ( RCF ) through the center of Santa Rosa, the largest city in the northern San Francisco Bay...
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View PDF for article title, Detailed Mapping and Rupture Implications of the 1 km Releasing Bend in the <span class="search-highlight">Rodgers</span> <span class="search-highlight">Creek</span> <span class="search-highlight">Fault</span> at Santa Rosa, Northern California
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Journal Article

The Most Recent Large Earthquake on the Rodgers Creek Fault, San Francisco Bay Area

Suzanne Hecker, Daniela Pantosti, David P. Schwartz, John C. Hamilton, Liam M. Reidy, Thomas J. Powers
Published: 01 June 2005
Bulletin of the Seismological Society of America (2005) 95 (3): 844–860.
DOI: https://doi.org/10.1785/0120040134
...Suzanne Hecker; Daniela Pantosti; David P. Schwartz; John C. Hamilton; Liam M. Reidy; Thomas J. Powers Abstract The Rodgers Creek fault ( rcf ) is a principal component of the San Andreas fault system north of San Francisco. No evidence appears in the historical record of a large earthquake...
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View PDF for article title, The Most Recent Large Earthquake on the <span class="search-highlight">Rodgers</span> <span class="search-highlight">Creek</span> <span class="search-highlight">Fault</span>, San Francisco Bay Area
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Journal Article

Structure and Mechanics of the Hayward–Rodgers Creek Fault Step-Over, San Francisco Bay, California

Tom Parsons, Ray Sliter, Eric L. Geist, Robert C. Jachens, Bruce E. Jaffe, Amy Foxgrover, Patrick E. Hart, Jill McCarthy
Published: 01 October 2003
Bulletin of the Seismological Society of America (2003) 93 (5): 2187–2200.
DOI: https://doi.org/10.1785/0120020228
...Tom Parsons; Ray Sliter; Eric L. Geist; Robert C. Jachens; Bruce E. Jaffe; Amy Foxgrover; Patrick E. Hart; Jill McCarthy Abstract A dilatational step-over between the right-lateral Hayward and Rodgers Creek faults lies beneath San Pablo Bay in the San Francisco Bay area. A key seismic hazard issue...
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View PDF for article title, Structure and Mechanics of the Hayward–<span class="search-highlight">Rodgers</span> <span class="search-highlight">Creek</span> <span class="search-highlight">Fault</span> Step-Over, San Francisco Bay, California
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Journal Article

Evolution of the Rodgers Creek–Maacama right-lateral fault system and associated basins east of the northward-migrating Mendocino Triple Junction, northern California

Robert J. McLaughlin, Andrei M. Sarna-Wojcicki, David L. Wagner, Robert J. Fleck, Victoria E. Langenheim, Robert C. Jachens, Kevin Clahan, James R. Allen
Journal: Geosphere
Published: 01 April 2012
Geosphere (2012) 8 (2): 342–373.
DOI: https://doi.org/10.1130/GES00682.1
...Robert J. McLaughlin; Andrei M. Sarna-Wojcicki; David L. Wagner; Robert J. Fleck; Victoria E. Langenheim; Robert C. Jachens; Kevin Clahan; James R. Allen Abstract The Rodgers Creek–Maacama fault system in the northern California Coast Ranges (United States) takes up substantial right-lateral motion...
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View PDF for article title, Evolution of the <span class="search-highlight">Rodgers</span> <span class="search-highlight">Creek</span>–Maacama right-lateral <span class="search-highlight">fault</span> system and associated basins east of the northward-migrating Mendocino Triple Junction, northern California
Add to Citation Manager for Evolution of the <span class="search-highlight">Rodgers</span> <span class="search-highlight">Creek</span>–Maacama right-lateral <span class="search-highlight">fault</span> system and associated basins east of the northward-migrating Mendocino Triple Junction, northern California
Image
Restoration of 28 km of long-term offset on Rodgers Creek fault zone based on correlation of fault scarp breccias and antiformal axes (in turquoise) at Taylor Mountain (TM) and Sears Point (SP), which may indicate minimum displacement since ca. 7 Ma. Gravity contours (in green) show restored basin geometry that does not completely align the gravity lows (hachures) beneath the Santa Rosa Plain with those beneath San Pablo Bay and Sonoma Valley. Compression marked by structural highs such as Trenton Ridge and the high between Cotati and Sonoma basins is not removed for this reconstruction, accounting for some of the mismatch of gravity lows. Present position of San Pablo Bay on east side of Rodgers Creek fault zone is shown in light blue for reference. Latitude and longitude grid is displaced with restoration of respective blocks on either side of Rodgers Creek fault zone. Other abbreviations: TMFZ—Taylor Mountain fault zone; CPFZ—Cooks Peak fault zone.

Restoration of 28 km of long-term offset on Rodgers Creek fault zone based ...

Published: 01 April 2012
Figure 11. Restoration of 28 km of long-term offset on Rodgers Creek fault zone based on correlation of fault scarp breccias and antiformal axes (in turquoise) at Taylor Mountain (TM) and Sears Point (SP), which may indicate minimum displacement since ca. 7 Ma. Gravity contours (in green) show
Image
(a) Seismicity around Rodgers Creek fault (1969–2003) showing earthquakes greater than magnitude 2. Data source: Northern California Earthquake Data Center; data contributed by Northern California Seismic Network, U.S. Geological Survey, Menlo Park, and Berkeley Seismological Laboratory, University of California, Berkeley. Locations of the 1969 magnitude 5.6 and 5.7 Santa Rosa events, which are highlighted, are from table 2 of Wong and Bott (1995). (b) Cross section shows seismicity within 5 km on either side of AA′.

(a) Seismicity around Rodgers Creek fault (1969–2003) showing earthquakes g...

Published: 01 June 2005
Figure 2. (a) Seismicity around Rodgers Creek fault (1969–2003) showing earthquakes greater than magnitude 2. Data source: Northern California Earthquake Data Center; data contributed by Northern California Seismic Network, U.S. Geological Survey, Menlo Park, and Berkeley Seismological Laboratory
Image
Earthquake ages and rupture scenarios for the Hayward–Rodgers Creek fault system. (a) Shaded rectangles represent the 95-percentile range and darker ellipses represent the 68-percentile range for preferred ages of the most recent event on the Rodgers Creek and north Hayward faults and the penultimate event on the south Hayward fault. Note that we use 1776 as a nominal cutoff for the age of paleoearthquakes along the fault zone, although Lienkaemper et al. (2002) incorporate the uncertainty in this historical constraint to obtain a modeled age for the event on the south Hayward fault that extends to 1790 (at 95-percentile confidence). The bar indicates the 1868 earthquake on the south Hayward fault. Not shown is the prepenultimate event on the south Hayward fault, which has a modeled age of a.d. 1530–1740. (b) Rupture scenarios proposed by W02. Small solid rectangles represent segment boundaries, or rupture end points, between the Rodgers Creek (RC), north Hayward (NH), and south Hayward (SH) faults (modified from Working Group on California Earthquake Probabilities, 2003, figure 3.2). The correspondence in earthquake ages shown in (a) supports the possibility of simultaneous rupture of the RC and NH (scenario 2), the NH and SH (scenario 3), or the RC, NH, and SH (scenario 4).

Earthquake ages and rupture scenarios for the Hayward–Rodgers Creek fault s...

Published: 01 June 2005
Figure 11. Earthquake ages and rupture scenarios for the Hayward–Rodgers Creek fault system. (a) Shaded rectangles represent the 95-percentile range and darker ellipses represent the 68-percentile range for preferred ages of the most recent event on the Rodgers Creek and north Hayward faults
Image
Predicted differential stress after 20 k.y. of Hayward–Rodgers Creek fault slip from finite-element modeling. Strong extensional stresses build in the crust between the strike-slip faults. Gray lines show the orientations of horizontal least principal stress (extension direction). If normal faults were to develop within the step-over, their expected orientation is perpendicular to the least-principal-stress directions.

Predicted differential stress after 20 k.y. of Hayward–Rodgers Creek fault ...

Published: 01 October 2003
Figure 8. Predicted differential stress after 20 k.y. of Hayward–Rodgers Creek fault slip from finite-element modeling. Strong extensional stresses build in the crust between the strike-slip faults. Gray lines show the orientations of horizontal least principal stress (extension direction
Journal Article

A new look back at the 1969 Santa Rosa, California, earthquakes

Ivan G. Wong, Jacqueline D. J. Bott
Published: 01 February 1995
Bulletin of the Seismological Society of America (1995) 85 (1): 334–341.
DOI: https://doi.org/10.1785/BSSA0850010334
... the great 1906 San Francisco earthquake and its aftershocks. The epicentral area coincides with a 1-km right step-over from the northwest-striking Rodgers Creek fault to the Healdsburg fault zone and a 6-km right step-over to the Maacama fault. The 1969 sequence and its relationship to the Healdsburg...
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Journal Article

Ground-Motion Modeling of Hayward Fault Scenario Earthquakes, Part I: Construction of the Suite of Scenarios

Brad T. Aagaard, Robert W. Graves, David P. Schwartz, David A. Ponce, Russell W. Graymer
Published: 01 December 2010
Bulletin of the Seismological Society of America (2010) 100 (6): 2927–2944.
DOI: https://doi.org/10.1785/0120090324
...Brad T. Aagaard; Robert W. Graves; David P. Schwartz; David A. Ponce; Russell W. Graymer Abstract We construct kinematic earthquake rupture models for a suite of 39 M w 6.6–7.2 scenario earthquakes involving the Hayward, Calaveras, and Rodgers Creek faults. We use these rupture models in 3D ground...
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View PDF for article title, Ground-Motion Modeling of Hayward <span class="search-highlight">Fault</span> Scenario Earthquakes, Part I: Construction of the Suite of Scenarios
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Journal Article

Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California

David L. Wagner, George J. Saucedo, Kevin B. Clahan, Robert J. Fleck, Victoria E. Langenheim, Robert J. McLaughlin, Andrei M. Sarna-Wojcicki, James R. Allen, Alan L. Deino
Journal: Geosphere
Published: 01 June 2011
Geosphere (2011) 7 (3): 658–683.
DOI: https://doi.org/10.1130/GES00626.1
... Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the Rodgers Creek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek–Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa...
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View PDF for article title, Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California
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Book Chapter

History and pre-history of earthquakes in wine and redwood country, Sonoma and Mendocino counties, California

Author(s)
Suzanne Hecker, Harvey Kelsey
... and on the Rodgers Creek fault in Sonoma County; the second part (Day 2) will go to stops in the town of Willits, on the northern Maacama fault, in Mendocino County. The Rodgers Creek and Maacama faults are major strands of the San Andreas fault system in northern California. The two faults are separated by a right...
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Abstract
View PDF for content titled, History and pre-history of earthquakes in wine and redwood country, Sonoma and Mendocino counties, California
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Abstract Contributors: Hans AbramsonWard, Geomatrix Consultants, Inc., 2101 Webster St., Suite 1200, Oakland, California 94612, USA; Julie Bawcom, California Geological Survey, 17501 North Highway 101, Willits, California 95490, USA; John Boatwright, U.S. Geological Survey, 345 Middlefield Rd., M.S. 977, Menlo Park, California 94025, USA; Todd Crampton, Geomatrix Consultants, Inc., 2101 Webster St., Suite 1200, Oakland, California 94612, USA; Wayne Goldberg, City Manager's Office, 100 Santa Rosa Ave., Rm. 10, Santa Rosa, California 95404, USA; Kathryn L.Hanson, Geomatrix Consultants, Inc., 2101 Webster St., Suite 1200, Oakland, California 94612, USA; Victoria E.Langenheim, U.S. Geological Survey, 345 Middlefield Rd., M.S. 989, Menlo Park, California 94025, USA; MortLarsen, Department of Geology, Humboldt State University, 1 Harpst St., Arcata, Cali-fornia 95521, USA; Gaye LeBaron, Press Democrat, P.O. Box 569, Santa Rosa, California 95402, USA; Darcy K.McPhee, U.S. Geological Survey, 345 Middlefield Rd., M.S. 989, Menlo Park, California 94025, USA; William V. McCormick, Kleinfelder, 2240 Northpoint Parkway, Santa Rosa, California 95407, USA; Robert J. McLaughlin, U.S. Geological Survey, 345 Middlefield Rd., M.S. 973, Menlo Park, California 94025, USA; Craig A.McCabe, U.S. Geological Survey, 345 Middlefield Rd., M.S. 973, Menlo Park, California 94025, USA; David P.Schwartz, U.S. Geological Survey, 345 Middlefield Rd., M.S. 977, Menlo Park, California 94025, USA; GarySimpson, SHN Consulting Engineers and Geologists, 812 W. Wabash Ave., Eureka, California 95501, USA; Frank H. (Bert)Swan, Consulting Geologist, 240 Laidley Street, San Francisco, California 94131, USA This guidebook is for a two-day trip: the first part (Day 1) takes place in and near the city of Santa Rosa and on the Rodgers Creek fault in Sonoma County; the second part (Day 2) will go to stops in the town of Willits, on the northern Maacama fault, in Mendocino County. The Rodgers Creek and Maacama faults are major strands of the San Andreas fault system in northern California. The two faults are separated by a right step and may be considered the northern extension of the Hayward and Calaveras faults, which branch from the San Andreas fault south of the San Francisco Bay area (Fig. 1 A). This system of faults accommodates almost a quarter of the total right-slip motion between the Pacific and North American tectonic plates. Slip is released in large, episodic earthquakes and, on some faults, such as the northern Maacama fault, by slow, steady creep.

Journal Article

Late Holocene Slip Rate and Ages of Prehistoric Earthquakes along the Maacama Fault Near Willits, Mendocino County, Northern California

Carol S. Prentice, Martin C. Larsen, Harvey M. Kelsey, Judith Zachariasen
Published: 21 October 2014
Bulletin of the Seismological Society of America (2014) 104 (6): 2966–2984.
DOI: https://doi.org/10.1785/0120140003
...Carol S. Prentice; Martin C. Larsen; Harvey M. Kelsey; Judith Zachariasen Abstract The Maacama fault is the northward continuation of the Hayward–Rodgers Creek fault system and creeps at a rate of 5.7±0.1 mm/yr (averaged over the last 20 years) in Willits, California. Our paleoseismic studies...
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View PDF for article title, Late Holocene Slip Rate and Ages of Prehistoric Earthquakes along the Maacama <span class="search-highlight">Fault</span> Near Willits, Mendocino County, Northern California
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Image
Strip map of the Rodgers Creek–Maacama fault system showing geologic features discussed in this paper that are offset across the Maacama fault zone (M–M′ and M.1; see Fig. 14); the combined Healdsburg and Rodgers Creek fault zones (H–H′; see Figs. 9 and 12) and across the southern Rodgers Creek fault zone south of Santa Rosa (R–R′; see Figs. 7, 9, and 11). Offset segments of antiform axis discussed in text are indicated in dark blue (see Fig. 11). Yellow boxes outline offset areas discussed in text and shown in more detail in Figures 9, 11, and 14. Lines of structure sections A, B, and C (Fig. 5) are shown with heavy blue lines. Geologic units, unit colors, symbols, and abbreviations are as in Figure 2, except that all Mesozoic rocks are here combined as one unit (brown). Additional abbreviations of geographic names include: CL—Cloverdale; GY—Geyserville; HLD—Healdsburg; SR—Santa Rosa; CO—Cotati; TR—Trenton; SBS—Sebastopol; PET—Petaluma; RV—Rincon Valley; NWSV—northwest Sonoma Valley; BV—Bennett Valley.

Strip map of the Rodgers Creek–Maacama fault system showing geologic featur...

Published: 01 April 2012
Figure 3. Strip map of the Rodgers Creek–Maacama fault system showing geologic features discussed in this paper that are offset across the Maacama fault zone (M–M′ and M.1; see Fig. 14 ); the combined Healdsburg and Rodgers Creek fault zones (H–H′; see Figs. 9 and 12 ) and across the southern
Journal Article

Diverse Pliocene-Quaternary tectonics in a transform environment, San Francisco Bay region, California

ATILLA AYDIN, BENJAMIN M. PAGE
Journal: GSA Bulletin
Published: 01 November 1984
GSA Bulletin (1984) 95 (11): 1303–1317.
DOI: https://doi.org/10.1130/0016-7606(1984)95<1303:DPTIAT>2.0.CO;2
... explanation. Models based on fault interaction seem to apply to certain cases. For example, the East Bay Hills domain, which is between the left-stepping Calaveras and Hayward–Rodgers Creek fault zones, is under compression resulting from interaction between the two strike-slip zones. Geological Society...
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Journal Article

Imaging P and S Attenuation in the Sacramento–San Joaquin Delta Region, Northern California

Donna Eberhart‐Phillips, Clifford Thurber, Jon B. Fletcher
Published: 29 July 2014
Bulletin of the Seismological Society of America (2014) 104 (5): 2322–2336.
DOI: https://doi.org/10.1785/0120130336
... fault zones (Fig.  6a ). This is most apparent along the Calaveras–Hayward–Rodgers Creek ( CHRC ) fault zone and may relate to a combination of highly fractured material from microseismic activity and basin sediments in the fault zones. Notably, the lowest Q is observed in the basin between...
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Journal Article

Implications of the northwestwardly younger age of the volcanic rocks of west-central California

KENNETH F. FOX, JR., ROBERT J. FLECK, GARNISS H. CURTIS, CHARLES E. MEYER
Journal: GSA Bulletin
Published: 01 May 1985
GSA Bulletin (1985) 96 (5): 647–654.
DOI: https://doi.org/10.1130/0016-7606(1985)96<647:IOTNYA>2.0.CO;2
... on the San Gregorio–Hosgri fault, 314 km on the San Andreas fault, 43 km on the Hayward-Rodgers Creek fault, and 28 km on the Carneros-Franklin-Sunol-Calaveras fault. On the basis of the age and restored position of the volcanic rocks, we judge that the locus of initial active volcanism migrated...
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Journal Article

Ground-Motion Modeling of Hayward Fault Scenario Earthquakes, Part II: Simulation of Long-Period and Broadband Ground Motions

Brad T. Aagaard, Robert W. Graves, Arthur Rodgers, Thomas M. Brocher, Robert W. Simpson, Douglas Dreger, N. Anders Petersson, Shawn C. Larsen, Shuo Ma, Robert C. Jachens
Published: 01 December 2010
Bulletin of the Seismological Society of America (2010) 100 (6): 2945–2977.
DOI: https://doi.org/10.1785/0120090379
... 6.7–7.2) involving the Hayward, Calaveras, and Rodgers Creek faults. For rupture on the Hayward fault, we consider the effects of creep on coseismic slip using two different approaches, both of which reduce the ground motions, compared with neglecting the influence of creep. Nevertheless, the scenario...
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Image
Map showing detail of link between Rodgers Creek and Maacama fault zones across Santa Rosa pull-apart basin (based on geologic maps of McLaughlin et al., 2003, 2008). Age of youngest folded Pleistocene–Pliocene deposits that underlie unfolded basin fill constrains timing of basin opening to ca. 0.8–1.2 Ma or later. The ∼6.5-km-long southwest side of the pull-apart basin bounded by the southern Rodgers Creek, Matanzas Creek, and Bennett Valley fault zones presumably represents composite displacement since opening of the basin ca. 1 Ma. Similarly, an ∼6.0-km-long length of the Maacama fault zone records slip since opening of northeast side of the basin. Dark gray filled circles are earthquake epicenters (Waldhauser and Schaff, 2008). Yellow boxes outline Glen Ellen gravels with Annadel-derived obsidian clasts that constrain offset across Southern Rodgers Creek and Healdsburg segments of Rodgers Creek fault zone (Fig. 3). D—downthrown; U—upthrown.

Map showing detail of link between Rodgers Creek and Maacama fault zones ac...

Published: 01 April 2012
Figure 9. Map showing detail of link between Rodgers Creek and Maacama fault zones across Santa Rosa pull-apart basin (based on geologic maps of McLaughlin et al., 2003, 2008). Age of youngest folded Pleistocene–Pliocene deposits that underlie unfolded basin fill constrains timing of basin
Image
Photographs of uplifted fault scarp-related breccia of the Taylor Mountain and Donnell Ranch and Sears Point areas offset across the southern Rodgers Creek fault zone. (A) West of Rodgers Creek fault zone. Cross-bedded angular breccia in Petaluma Formation along Warrington Road southwest of Taylor Mountain, (Fig. 3, R′; Fig. 4, stratigraphic section 1; Fig. 5, cross-section C). Breccia was largely shed from fault scarps bounding underlying rhyolite and dacite of Cooks Peak. In left photo hand of person to left (west) rests on subround cobble of Franciscan sandstone. Coarse angular material is rhyodacitic debris, locally conspicuously slickensided. In right photo person points to rounded pebble-sized Franciscan clasts composing a minor (fluvial) component of breccia matrix. Left (west dipping) foreset beds are visible in both photos. (B) East of Rodgers Creek fault zone. Correlative fluvial deposits on the Donnell Ranch, east of Sears Point (Fig. 3, R). In photo on left, bedded gravelly fluvial deposits have a tuff-rich matrix; clasts include round to subround Tertiary volcanic clasts, and nonvolcanic Franciscan-derived clasts are in moderate abundance, in addition to angular rhyolite to dacite clasts identical to those in the breccia of Warrington Road. In right photo outcrops are composed dominantly of unsorted angular rhyolitic to dacitic debris, with bedding defined by vertical alternation of coarse and fine material. In both areas separated across the Rodgers Creek fault zone, isolated angular clasts in breccia reach dimensions &gt;3 m.

Photographs of uplifted fault scarp-related breccia of the Taylor Mountain ...

Published: 01 April 2012
Figure 6. Photographs of uplifted fault scarp-related breccia of the Taylor Mountain and Donnell Ranch and Sears Point areas offset across the southern Rodgers Creek fault zone. (A) West of Rodgers Creek fault zone. Cross-bedded angular breccia in Petaluma Formation along Warrington Road