Quaternary Fault and Fold Database of the United States

qfaults web comp As of January 12, 2017, the USGS maintains a limited number of metadata fields that characterize the Quaternary faults and folds of the United States. For the most up-to-date information, please refer to the interactive fault map.

Sierra Madre fault zone, San Fernando section (Class A) No. 105b

Last Review Date: 2000-06-01

citation for this record: Treiman, J.A., compiler, 2000, Fault number 105b, Sierra Madre fault zone, San Fernando section, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, https://earthquakes.usgs.gov/hazards/qfaults, accessed 04/23/2024 01:59 AM.

Synopsis General: In general the Sierra Madre-Cucamonga fault zone marks the southern margin of uplift of the San Gabriel Mountains, although the Santa Susana fault extends the zone of south-vergent uplift west of these mountains. Only local portions of the fault zone have had detailed paleoseismic investigations, and those have had fairly limited results. Published slip rates vary widely along the fault zone. The best-understood part of the fault is the easternmost section, the Cucamonga fault zone, with excellent geomorphic expression, several trenches, and age control from radiocarbon and soil stratigraphic studies. These studies have demonstrated multiple Holocene events on several strands of the Cucamonga fault and a minimum slip rate of 4.5 mm/yr. Two studies on the central and eastern portions of the Sierra Madre fault zone have indicated that recurrence intervals between large events (M greater than or equal to 7) seem to be long (perhaps 7–8 k.y. or longer). The slip rate on the Sierra Madre fault appears to be considerably less than the Cucamonga fault, perhaps as low as 1 mm/yr or less. Studies on the San Fernando fault zone indicate a somewhat shorter recurrence interval of perhaps as much as 4,000 yr. The Santa Susana fault is less well understood, but has been inferred to have a slip rate greater than 5 mm/yr.

Sections: This fault has 8 sections. The Santa Susana, San Fernando, Sierra Madre and Cucamonga fault zones are four basic units of this fault zone. Santa Susana, itself, has been divided structurally into three parts (Yeats, 1987 #6113; Yeats and others, 1994 #6114, see discussion of section 105a) but is treated here as one section. The Sierra Madre fault zone, along with the San Fernando fault zone, has been divided into three to seven elements. Segmentation of the Sierra Madre fault has been proposed based on the identification of several, convex-to-the-south, "salients" (Proctor and others, 1972 #6100; Ehlig, 1975 #6088; Wesnousky, 1986 #5305; Petersen and Wesnousky, 1994 #5962). However, it has not been demonstrated that rupture would be restricted to an individual segment in an earthquake. Sierra Madre segment A (Wesnousky, 1986 #5305) is not considered by Crook and others (1987 #5956) as part of the Sierra Madre fault zone, but rather is called the Vasquez Creek fault (after Miller, 1928 #5961), a southern branch of the San Gabriel fault. Segments B through E of Wesnousky (1986 #5305) after Proctor and others (1972 #6100) and Ehlig (1975 #6088) are retained in this compilation as sections. Morton and Matti (1987 #6099) discuss possible segmentation of the Cucamonga fault zone (but it is treated here as one section). Walls and others (1997 #6110) suggest at least two and possibly three segments for the San Fernando-Sierra Madre-Cucamonga fault zone (San Fernando, Sierra Madre and Cucamonga) based on differing uplift rates. In support of a lesser number of segments, Tucker and Dolan (2001 #6107) suggest that the entire Sierra Madre section, from Altadena to San Dimas, may rupture in single events.
Name comments General:

Section: Section is named for the rupture zone from the 1971 San Fernando earthquake (Wentworth and others, 1971 #6112) and extends from vicinity of Los Angeles Reservoir (site of San Fernando Reservoir) to Big Tujunga Canyon. The rupture zone as originally described included several "segments"—Mission Wells, Sylmar and Tujunga segments (U.S. Geological Survey Staff, 1971 #6108; Wentworth and others, 1971 #6112), with the Reservoir segment being added at the western end (named by Weber, 1975 #6111 after the Reservoir fault) and the Lakeview fault segment being distinguished within the eastern end of the Tujunga segment (Kahle, 1975 #6094). "Lakeview thrust fault" was described earlier by Proctor and others (1972 #6100), roughly corresponding to the original Tujunga "segment". San Fernando fault zone also includes Kagel fault, Wildwood fault, Bartholomaus fault (Proctor and others, 1972 #6100), and Sunland fault (Hill, 1930 #6091).

Fault ID: Refers to numbers 344 (Santa Susana fault), 355 (unnamed faults), 356 (San Fernando fault), 357 (Sierra Madre fault), 385 (Clamshell and Sawpit Canyon faults), 395 (Duarte fault), and 399 (Cucamonga fault) of Jennings (1994 #2878). Also refers to numbers 68 (Santa Susana fault), 69 (San Fernando fault), 83 (Sierra Madre fault), 84 (Duarte fault), 85 (Clamshell-Sawpit fault zone), and 86 (Cucamonga fault) of Ziony and Yerkes (1985 #5931).
County(s) and State(s) LOS ANGELES COUNTY, CALIFORNIA
Physiographic province(s) PACIFIC BORDER
Reliability of location Good
Compiled at 1:24,000 scale.

Comments: Location of fault transferred by inspection from 1:18,000 map of Barrows and others (1975 #6082).

Geologic setting Sierra Madre fault zone, within the eastern part of the Transverse Ranges, refers to the entire 125-km-long complex zone of mechanically related thrust and reverse faults that grossly demarcate the base of the San Gabriel Mountains from San Fernando Pass on the west to Cajon Pass on the east, and also includes the Santa Susana fault to the west (Ehlig, 1975 #6088; Crook and others, 1987 #5956; Morton and Matti, 1987 #6099; Yeats, 1987 #6113). Reverse slip on this fault zone has contributed to the 2–3 km elevation of the mountain range (Walls, 2001 #6109).

Length (km) This section is 23 km of a total fault length of 128 km.
Average strike N85°W (for section) versus N86°W (for whole fault)
Sense of movement Thrust

Comments: Thrust and sinistral strike-slip components on various sections described by U.S. Geological Survey Staff, (1971 #6108), Barrows (1975 #6081), Kahle (1975 #6094) and Weber (1975 #6111); reverse left-oblique per Ziony and Yerkes (1985 #5931).

Dip 50° N.

Comments: 40° is reported by Crook and others (1987 #5956); Ziony and Yerkes (1985 #5931) cite 15–50° near surface with 35° at depth.

Paleoseismology studies Site 105-1, Oak Hill: trench across 1971 surface rupture exposed evidence for prior displacement; 14C-dated wood fragment provided minimum age for prior event (Bonilla, 1973 #6083).

Site 105-5, Sylmar filtration plant: trenches across several secondary faults north of mapped trace indicated latest Pleistocene faulting (<35–40 ka) but older than 5–10 ka (Spellman and others, 1984 #6103).

Site 105-9, Bartholomaus Ranch: trenches across 1971 surface rupture found evidence for prior displacement of roughly equal magnitude to 1971; 14C-dated detrital charcoal provided maximum age of penultimate event (Fumal and others, 1995 #6089).

Geomorphic expression Abrupt mountain front along Tujunga and Lakeview strands; historic and older scarps; drainage constriction and incised drainages; strath terraces in hanging wall block (Walls and others, 1997 #6110).

Age of faulted surficial deposits Holocene colluvium (Bonilla, 1973 #6083; Fumal and others, 1995 #6089; Lindvall and others, 1995 #6095); late Pleistocene fans (Lindvall and others, 1995 #6095); Pleistocene fans (including Pacoima Formation) and bedrock (including Saugus Formation); Tertiary bedrock (Barrows and others, 1975 #6082)
Historic earthquake
Most recent prehistoric deformation latest Quaternary (<15 ka)

Comments: <3.5–4 ka (Fumal and others, 1995 #6089); possibly 100 to 300 yr BP (Bonilla, 1973 #6083); historic event (M6.6) in 1971

Recurrence interval 200–2,000 yrs

Comments: up to 2000 yrs (average based on two events within past 3.5–4 ka, Fumal and others (1995 #6089); 200 yrs (Working Group on California Earthquake Probabilities (1995 #4945) based on Bonilla data); 455 yr (calculated from assumed slip per event and slip rate, Dolan and others (1995 #5965).
Slip-rate category Between 1.0 and 5.0 mm/yr

Comments: 4.0±2.0 mm/yr extrapolated by Working Group on California Earthquake Probabilities (1995 #4945) from the Cucamonga fault (section 105h. Based on faulted and uplifted fluvial terraces, Lindvall and others (1995 #6095) suggested about 2 mm/yr for past 20–30 ka. This was revised to a minimum of about 1 mm/yr uplift rate by Walls and others (1997 #6110) and revised again to 1.1 +1.3/-0.4 mm/yr (Walls, 2001 #6109) based on vertical separation rates of terraces. Slip rate assigned by Petersen and others (1996 #4860) for probabilistic seismic hazard assessment for the State of California was 2.0 mm/yr (with minimum and maximum assigned slip rates of 1.0 mm/yr and 3.0 mm/yr, respectively).
Date and Compiler(s) 2000
Jerome A. Treiman, California Geological Survey
References #6080 Arnold, R., and Strong, A.M., 1905, Some crystalline rocks of the San Gabriel Mountains, California: Geological Society of America Bulletin, v. 16, p. 183-204.

#6081 Barrows, A.G., 1975, Chapter 7—Surface effects and related geology of the San Fernando earthquake in the foothill region between Little Tujunga and Wilson Canons, in Oakeshott, G.B., ed., San Fernando, California, earthquake of 9 February 1971: California Division of Mines and Geology Bulletin 196, p. 97–117.

#6082 Barrows, A.G., Kahle, J.E., Saul, R.B., and Weber, F.H., Jr., 1975, Geologic map of the San Fernando earthquake area, in Oakeshott, G.B., ed., San Fernando, California, earthquake of 9 February 1971:California Division of Mines and Geology Bulletin 196, Pl. 2, scale 1:18,000.

#6083 Bonilla, M.G., 1973, Trench exposures across surface fault ruptures associated with San Fernando earthquake, in Murphy, L.M., ed., San Fernando, California, earthquake of February 9, 1971:U.S. Department of Commerce, NOAA, Washington, D.C. Geological and Geophysical Studies, v. III, p. 173-182.

#5956 Crook, R., Jr., Allen, C.R., Kamb, B., Payne, C.M., and Proctor, R.J., 1987, Quaternary geology and seismic hazard of the Sierra Madre and associated faults, western San Gabriel Mountains, in Recent reverse faulting in the Transverse Ranges, California: U.S. Geological Survey Professional Paper 1339, p. 27–63, scale 1:24,000.

#5965 Dolan, J.F., Sieh, K., Rockwell, T.K., Yeats, R.S., Shaw, J., Suppe, J., Huftile, G.J., and Gath, E.M., 1995, Prospects for larger or more frequent earthquakes in the Los Angeles metropolitan region: Science, v. 267, p. 199-205.

#6088 Ehlig, P.L., 1975, Chapter 2-Geologic framework of the San Gabriel Mountains, in Oakeshott, G.B., ed., San Fernando, California, earthquake of 9 February 1971:California Division of Mines and Geology Bulletin 196, p. 7-18.

#6089 Fumal, T.E., Davies, A.B., Frost, W.T., O?Donnell, J.O., Sega, G., and Schwartz, D.P., 1995, Recurrence studies of the Tujunga segment of the 1971 San Fernando, California, earthquake: Eos, Transactions of the American Geophysical Union, v. 76, no. 46, supplement, p. 364.

#6091 Hill, M.L., 1930, Structure of the San Gabriel Mountains, north of Los Angeles, California: University of California Publications, Bulletin of the Department of Geological Sciences, v. 19, no. 6, p. 137-170.

#6093 Jahns, R.H., and Proctor, R.J., 1975, The San Gabriel and Santa Susana—Sierra Madre fault zones in the western and central San Gabriel Mountains, southern California: Geological Society of America Abstracts With Programs, v. 7, no. 3, p. 329.

#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.

#6094 Kahle, J.E., 1975, Chapter 8—Surface effects and related geology of the Lakeview fault segment of the San Fernando fault zone, in Oakeshott, G.B., ed., San Fernando, California, earthquake of 9 February 1971:California Division of Mines and Geology Bulletin 196, p. 119-135.

#6014 Kew, W.S.W., 1924, Geology and oil resources of a part of Los Angeles and Ventura Counties, California: U.S. Geological Survey Bulletin 753, 202 p.

#6095 Lindvall, S.C., Rockwell, T.K., Walls, C., and Bornyasz, M., 1995, Late Quaternary deformation of Pacoima Wash terraces in the vicinity of the 1971 San Fernando earthquake rupture, northern San Fernando Valley, California: Eos, Transactions of the American Geophysical Union, v. 76, no. 46, Supplement, p. F362-F363.

#5961 Miller, W.J., 1928, Geomorphology of the southwestern San Gabriel Mountains of California: University of California, Bulletin of the Department of Geological Sciences, v. 17, no. 6, p. 193-240.

#6099 Morton, D.M., and Matti, J.C., 1987, The Cucamonga fault zone—Geologic setting and Quaternary history, in Recent reverse faulting in the Transverse Ranges, California: U.S. Geological Survey Professional Paper 1339, p. 179-203, scale 1:24,000.

#5962 Petersen, M.D., and Wesnousky, S.G., 1994, Review, fault slip rates and earthquake histories for active faults in southern California: Bulletin of the Seismological Society of America, v. 84, no. 5, p. 1608-1649.

#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.

#6100 Proctor, R.J., Crook, R., Jr., McKeown, M.H., and Moresco, R.L., 1972, Relation of known faults to surface ruptures, 1971 San Fernando earthquake, southern California: Geological Society of America Bulletin, v. 83, p. 1601-1618.

#6103 Spellman, H.A., Stellar, J.R., Shlemon, R.J., Sheahan, N.T., and Mayeda, S.H., 1984, Trenching and soil dating of Holocene faulting for a water filtration plant site, Sylmar, California: Bulletin of the Association of Engineering Geologists, v. XXI, p. 89-100.