Partial Report for Greenville fault zone, Marsh Creek-Greenville section (Class A) No. 53b
Compiled in cooperation with the California Geological Survey
citation for this record: Bryant, W.A., and Cluett, S.E., compilers, 2002, Fault number 53b, Greenville fault zone, Marsh Creek-Greenville section, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, http://earthquakes.usgs.gov/hazards/qfaults, accessed 04/24/2014 02:34 AM.
|Synopsis||General: Historically active dextral strike-slip faults located in the Diablo Range. Minor surface fault rupturing was associated with the January 1980 Livermore Valley earthquakes (Bonilla and others, 1980 #5366; Hart and others, 1980 #5376; Bolt and others, 1981 #5365). Most of the fault trace is based on geologic and geomorphic evidence from detailed reconnaissance-level mapping by Herd (1977 #5364), Dibblee (1980 #5335, 1980 #5370, 1980 #5371, 1980 #5372), Hart (1981 #5375), and Earth Sciences Associates (1982 #5374) as reported in Wright and others (1982 #5357). Trench investigations along the Marsh Creek-Greenville section [53b] document latest Pleistocene and Holocene displacement. Partial late Quaternary slip rates of 0.1-0.7 mm/yr have been reported by Wright and others (1982 #5357) and Sweeney (1982 #5361). Unruh and Sawyer (1995 #5339, 1998 #5360) suggested that the late Quaternary slip rate might be as high as 3 mm/yr on the basis of structural modeling. Sawyer and Unruh (2002 #5362) calculated a Holocene dextral slip rate of 4.1?1.8 mm/yr at the Laughlin Road site [53b-1].|
Sections: This fault has 4 sections. There is insufficient evidence to establish seismogenic segments for the Greenville fault, thus we treat them as sections herein. Wright and others (1982 #5357) defined three segments based on differences in geomorphic expression of the fault zone and different apparent ages of activity. From north to south these segments include the Clayton, Marsh Creek-Greenville, and Arroyo Mocho segments. Unruh and Sawyer (1998 #5360) defined four sections based on differences in geomorphic expression and structural character of the fault zone. From north to south their sections are named Livermore, Arroyo Mocho, San Antonio Valley, and Coyote Creek. The Livermore section of Unruh and Sawyer (1998 #5360) mostly corresponds with the southern Marsh Creek-Greenville segment of Wright and others; the Arroyo Mocho section of Unruh and Sawyer (1998 #5360) generally corresponds with the Arroyo Mocho segment of Wright and others (1982 #5357). The Coyote Creek section of Unruh and Sawyer (1998 #5360) is not considered here because Quaternary displacement has not been demonstrated.
|County(s) and State(s)||CONTRA COSTA COUNTY, CALIFORNIA |
ALAMEDA COUNTY, CALIFORNIA
|Physiographic province(s)||PACIFIC BORDER |
|Reliability of location||Good|
Compiled at 1:62,500 scale.
|Geologic setting||This dextral strike-slip fault zone borders the eastern side of Livermore Valley and is considered to be part of the larger San Andreas fault system in the central Coast Ranges. The fault zone extends from northwest of Livermore Valley along the Marsh Creek and Clayton faults towards Clayton Valley. Unruh and Sawyer (1995 #5339, 1998 #5360) suggested that slip from the Greenville fault is transferred to the Concord fault  along the Mt. Diablo fold and thrust belt and that only minimal slip continues to the Clayton fault [53a]. The fault zone extends southeastward into San Antonio Valley, offsets late Mesozoic rocks of the Franciscan Complex. Southeast of Livermore Valley the fault is located within the uplifted Diablo Range and controls the generally linear drainage course of Arroyo Mocho, Colorado, and Sweetwater Creeks. Maximum dextral displacement along the Greenville fault zone is about 8.5-9 km, based on 9 km of dextral offset of a late Mesozoic serpentinite body and about 8.5 km dextral offset of the Tesla fault (Cotton, 1972 #5348; Sweeney, 1982 #5361).|
|Length (km)||This section is 35 km of a total fault length of 91 km.|
|Average strike||N35°W (for section) versus N30°W (for whole fault)|
|Sense of movement||Dextral|
|Dip Direction||NE; V|
|Paleoseismology studies||Two detailed studies have been conducted along the Marsh Creek-Greenville section: |
The Laughlin Road site [53b-1] of Sawyer and Unruh (2002 #5362) involved the excavation of two fault-normal and two fault-parallel trenches in order to determine the Holocene slip rate of the Greenville fault. These trenches exposed a sequence of alluvial-fan deposits offset by high-angle faults, some characterized by sub-horizontal slickensides on clay gouge. Some fractures extended to the modern land surface, consistent with surface rupture observations following the 1980 Livermore earthquakes.
Site 53b-2. A single trench was excavated across a strand of the Greenville fault at site 53b-2 by the U.S. Geological Survey in 1975 (reported in Hart and others, 1980 #5376). The trench, which crossed an east-facing scarp, exposed a single, steeply (about 75?) southwest-dipping fault that places Miocene Cierbo(?) Formation against late Pleistocene alluvium estimated to be about 40 ka (Qoa2 unit of Herd, 1977 #5364) on the basis of the development of an overlying B soil horizon. The fault extends into and may displace the B horizon, indicating a post-40 ka time of offset.
Site 53b-3. A single trench was excavated across a subtle scarp located along an east-facing bench (Earth Sciences Associates, 1982 #5374) as reported in Wright and others (1982 #5357). Trench G-10 exposed a near vertical, 1.5-m-wide fault zone that displaces a 35-40 ka paleosol. A scarp-derived colluvial wedge, estimated to be 10-12 ka from soil development, is also displaced. Wright and others (1982 #5357) reported that the youngest soil unit (estimated to be 2-4 ka) is also offset, although soil-fault relations are not clear. Wright and others (1982 #5357) estimated about 3:1 horizontal to vertical slip components on the basis of rake of slickenlines observed in trench G-10.
|Geomorphic expression||expression The Marsh Creek-Greenville section is marked by a roughly 1-km-wide zone of discontinuous surface fault traces with geomorphic expression characteristic of dextral strike-slip displacement such as closed depressions, linear scarps, linear drainages and ridges, side-hill benches, dextrally deflected drainages, shutter ridges, aligned benches, saddles and troughs, linear tonal contrasts on young (Holocene?) alluvium (Hart, 1981 #5375; Wright and others, 1982 #5357; Unruh and Sawyer, 1998 #5360). Wright and others (1982 #5357) considered the Marsh Creek-Greenville section generally to be less well developed and youthful than traces delineating the Arroyo Mocho section [53c].|
|Age of faulted surficial deposits||A trench exposure just north of Highway 580 in the northern Livermore Valley (Herd, 1977 #5364) shows that late Pleistocene alluvium is displaced and the fault extends upward into an overlying B soil horizon. The age of this B soil horizon is not known, but it may be latest Pleistocene (10-30 ka). South of Livermore Valley, the fault offsets a paleosol and colluvium thought to be about 10-12 ka (trench G-10 of Earth Sciences Associates, 1982 #5374), as reported in Wright and others (1982 #5357). Wright and others (1982 #5357) also reported that a 2-4 ka soil is offset, but fault/soil relations are not clear in trench log G-10. It is presumed that the age of the deposits is estimated based on soil profile development.|
|Most recent prehistoric deformation||Latest Quaternary (<15 ka)|
|Slip-rate category||Between 1.0 and 5.0 mm/yr|
|Date and Compiler(s)||2002|
William A. Bryant, California Geological Survey
Sereyna E. Cluett, California Geological Survey
|References||#5365 Bolt, B.A., McEvilly, T.V., and Uhrhammer, R.A., 1981, The Livermore Valley, California, earthquake sequence of January 1980: Bulletin of the Seismological Society of America, v. 71, no. 2, p. 451-463.|
#5366 Bonilla, M.G., Lienkaemper, J.J., and Tinsley, J.C., 1980, Surface faulting near Livermore, California, associated with the January 1980 earthquakes: U.S. Geological Survey Open-File Report 80-523, 32 p.
#5368 Brabb, E.E., Sonneman, H.S., and Switzer, J.R., Jr., 1971, Preliminary geologic map for the Mt. Diablo-Byron area, Contra Costa, Alameda, and San Joaquin Counties, California: U.S. Geological Survey Basic Data Contribution 28, scale 1:62,500.
#5369 Colburn, I.P., 1961, The tectonic history of Mount Diablo, California: Stanford University, unpublished Ph.D. dissertation, 234 p.
#5348 Cotton, W.R., 1972, Preliminary geologic map of the Franciscan rocks in the central part of the Diablo Range, Santa Clara and Alameda Counties, California: U.S. Geological Survey Miscellaneous Field Studies Map MF-343 (Basic Data Contribution 39), 2 sheets, scale 1:62,500.
#5371 Dibblee, T.W., Jr., 1980, Preliminary geologic map of the Byron Hot Springs quadrangle, Alameda and Contra Costa Counties, California: U.S. Geological Survey Open-File Map 80-534, scale 1:24,000.
#5335 Dibblee, T.W., Jr., 1980, Preliminary geologic map, Clayton quadrangle: U.S. Geological Survey Open-File Report 80-547.
#5373 Dibblee, T.W., Jr., 1980, Preliminary geologic map of the Midway quadrangle, Alameda County, California: U.S. Geological Survey Open-File Map 80-535, scale 1:24,000.
#5370 Dibblee, T.W., Jr., 1980, Preliminary geologic map of the Tassajara quadrangle, Alameda and Contra Costa Counties, California: U.S. Geological Survey Open-File Map 80-544, scale 1:24,000.
#5372 Dibblee, T.W., Jr., 1980, Preliminary geologic map of the Altamont quadrangle, Alameda County, California: U.S. Geological Survey Open-File Map 80-538, scale 1:24,000.
#5374 Earth Sciences Associates, 1982, Seismotectonic study of Contra Loma dam and vicinity: Final Report to U.S. Bureau of Reclamation, Denver, Colorado.
#5375 Hart, E.W., 1981, Recently active strands of the Greenville fault, Alameda, Contra Costa, and Santa Clara Counties, California: California Division of Mines and Geology Open-File Report 81-8, scale 1:24,000.
#5376 Hart, E.W., Bedrossian, T., and Ridley, A., 1980, Greenville fault, east Livermore Valley: California Division of Mines and Geology, field trip guide, April 12, 1980, p. 9.
#5364 Herd, D.G., 1977, Geologic map of the Las Positas, Greenville, and Verona faults, eastern Alameda County, California: U.S. Geological Survey Open-File Report 77-689, 25 p., scale 1:24,000.
#5363 Huey, A.S., 1948, Geology of the Tesla quadrangle, California: California Division of Mines Bulletin 140, 5 p., 3 pls.
#2878 Jennings, C.W., 1994, Fault activity map of California and adjacent areas, with locations of recent volcanic eruptions: California Division of Mines and Geology Geologic Data Map 6, 92 p., 2 pls., scale 1:750,000.
#4860 Petersen, M.D., Bryant, W.A., Cramer, C.H., Cao, T., Reichle, M.S., Frankel, A.D., Lienkaemper, J.J., McCrory, P.A., and Schwartz, D.P., 1996, Probabilistic seismic hazard assessment for the State of California: California Department of Conservation, Division of Mines and Geology Open-File Report 96-08 (also U.S. Geological Open-File Report 96-706), 33 p.
#5362 Sawyer, T.L., and Unruh, J.R., 2002, Paleoseismic investigation of the Holocene slip rate on the Greenville fault, eastern San Francisco Bay area, California: U.S. Geological Survey Final Technical Report for the National Earthquake Hazards Reduction Program, Award # 00HQGR0055, 24 p., 1 pl.
#5361 Sweeney, J.J., 1982, Magnitudes of slip along the Greenville fault in the Diablo Range and Corral Hollow areas, in Hart, E.W., and others, eds., Proceedings, Conference on earthquake hazards in the eastern San Francisco Bay area: California Division of Mines and Geology Special Publication 62, p.137-146.
#5339 Unruh, J.R., and Sawyer, T.L., 1995, Late Cenozoic growth of the Mt. Diablo fold and thrust belt, central Contra Costa County, California, and implications for transpressional deformation of the northern Diablo Range [abs.]: American Association of Petroleum Geologists, 1995 Pacific Section Convention Abstracts, 47 p.
#5360 Unruh, J.R., and Sawyer, T.L., 1998, Paleoseismic investigation of the northern Greenville fault, eastern San Francisco Bay Area, California: U.S. Geological Survey Final Technical Report for the National Earthquake Hazards Reduction Program, Award # 1434-HQ-97-GR-03146, 34 p., 8 maps, scale 1:24,000.
#5359 Vickery, F.P., 1925, The structural dynamics of the Livermore region: Journal of Geology, v. 33, p. 608-628.
#1216 Working Group on Northern California Earthquake Potential, 1996, Database of potential sources for earthquakes larger than magnitude 6 in northern California: U.S. Geological Survey Open-File Report 96-705, 40 p.