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Organization Title

CALIFORNIA DEPARTMENT OF CONSERVATION
DIVISION OF MINES AND GEOLOGY
OPEN-FILE REPORT 96-08

U.S. DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 96-706

 

APPENDIX A

CALIFORNIA FAULT PARAMETERS

FAULT NAME AND GEOMETRY
(ss) strike slip, (r) reverse, (n) normal
(rl) rt. lateral, (ll) left lateral, (o) oblique
LENGTH
(km)
SLIP
RATE
(mm/yr)
RANK
(1)
Mmax
(2)
CHAR.
RATE
(events/yr)
R.I.
(3)
Down dip
Width
(km)(4)
ruptop
(5)
rupbot
(6)
rake dip daz
(7)
Endpt N Endpt S COMMENTS

B FAULTS (Continued)

TRANSVERSE RANGES AND LA BASIN

Big Pine
(ll-ss)
41 4 0.80 0.80 P 6.7 0.00102 984 13 2 0 13 0 90 0 -119.01;34.82 -119.40;34.66 Poorly constrained Plio-Pleistocene slip rate > 0.8 mm/yr from Kahle (1966).
Clamshell-Sawpit
(r, 45 NW)
16 2 0.50 0.50 U 6.5 0.00068 1461 18 2 0 13 90 45 315 -117.85;34.24 -118.00;34.18 Unconstrained slip rate reported by Dolan, et al (1995), based on geomorphic expression of fault.
Cucamonga
(r, 45 N)
28 3 5.00 2.00 M 7.0 0.00154 650 18 2 0 13 90 45 0 -117.73;34.13 -117.43;34.18 Slip rate based on cumulative vertical displacement across three strands reported by Morton and Matti (1987, 1991). Maximum magnitude and recurrence of about 650 yrs based on 2 m average displacements.
Hollywood
(ll-r-o, 70 N)
17 2 1.00 0.50 P 6.4 0.00160 626 14 2 0 13 0 70 0 -118.41;34.08 -118.23;34.12 Slip rate estimated by authors, based on similar rationale for Santa Monica fault zone. Dolan, et al (1995) reported a slip rate of 1.0-1.5 mm/yr.
Holser
(r, 65 S)
20 2 0.40 0.40 P 6.5 0.00053 1878 14 2 0 13 90 65 180 -118.75;34.44 -118.55;34.42 Slip rate estimated by authors based on offset of base of Plio-Pleistocene Saugus Fm. reported by Stitt (1986).
Malibu Coast
(ll-r-o, 75 N)
37 4 0.30 0.20 P 6.7 0.00034 2908 13 2 0 13 0 75 0 -118.93;34.05 -118.53;34.03 Slip rate is horizontal component of slip based on left-laterally deflected drainages incised in terrace surface (Stage 7? or 9?) reported by Treiman (1994).
Mission Ridge-
Arroyo Parida-
Santa Ana

(r, 60 N)
65 7 0.40 0.20 M 6.7 0.00093 1076 15 2 0 13 90 60 0 -119.90;34.43 -119.17;34.47 Minimum dip-slip rate based on Rockwell, et al (1984). Assumption that half of 65 km length ruptures. Total length includes More Ranch fault.
Newport-Inglewood

(rl-ss)
64 6 1.00 0.50 P 6.9 0.00099 1006 13 2 0 13 180 90 0 -118.37;34.03 -117.92;33.61 Mio-Pliocene slip rate of 0.5mm/yr reported by Freeman, et al. (1992). Offsets observed in the Huntington Beach area indicate significant Holocene displacement. Apparent vertical separation of 0.46 m of 3-4ka A soil horizon is suggestive of higher slip rate. If apparent vertical separation reflects actual vertical displacement, then H:V ratio of 20:1 for fault (Freeman, et al., 1992) would suggest Holocene rate of 2 to 3 mm/yr. We use 1 mm/yr for fault, based on WGCEP (1995).
Oak Ridge (onshore)
(r, 65 S)
50 5 4.00 2.00 P 6.9 0.00334 299 14 2 1 14 90 65 180 -119.21;34.25 -118.72;34.4 Dip-slip rate estimated by authors is composite of several published rates (Yeats, 1988; Levi & Yeats, 1993; Huftile, 1992; Yeats, et al., 1994; WGCEP, 1995)..
Palos Verdes
(rl-ss)
96 10 3.00 1.00 M 7.1 0.00154 650 13 2 0 13 180 90 0 -118.56;33.97 -117.94;33.28 Fault is predominantly rlss (H:V is 10:1) according to Henyey (1994). Slip rate is based on rl offset of ancestral channel of Los Angeles River (Stephenson et al., 1995). McNeilan, et al., (1996) reported an average recurrence of 650 yrs.
Pleito Thrust
(r, 20 S)
44 4 2.00 1.00 M 7.2 0.00142 706 38 2 0 13 90 20 180 -119.30;34.94 -118.87;34.95 Holocene slip rate based on offset Tecuya alluvial fan reported by Hall (1984).
Raymond
(ll-r-o, 75 N)
21 2 0.50 0.30 P 6.5 0.00065 1541 13 2 0 13 0 75 0 -118.22;34.12 -118.00;34.17 Slip rate estimated by authors is poorly constrained, based on focal mechanism of 1988 Pasadena earthquake and assumed vertical component of offset reported by Crook et al. (1987). Crook, et al. reported average recurrence interval of 3000 yrs. Dolan, et al. (1995) reported 0.4mm/yr slip rate for Raymond flt.
Red Mountain
(r, 60 N)
39 4 2.00 1.00 P 6.8 0.00197 507 15 2 0 13 90 60 350 -119.65;34.36 -119.28;34.40 Slip rate based on summation of two strands of Red Mtn. flt at Punta Gorda reported in Clark, et al., 1984).
San Cayetano
(r, 60 N)
44 4 6.00 3.00 P 6.8 0.00668 150 15 2 0 13 90 60 10 -119.17;34.46 -118.76;34.44 Dip-slip rate estimated by authors is composite of several published rates (Rodkwell, 1983, 1988; Yeats, 1983; Molnar, 1991; Levi & Yeats, 1993; Huftile, 1992; WGCEP, 1995).
San Gabriel
(rl-ss)
72 7 1.00 0.50 P 7.0 0.00079 1264 13 2 0 13 180 90 0 -118.88;34.71 -118.28;34.32 Poorly constrained long term slip rate reported by Yeats, et al. (1994). Slip rates range from 1-3 mm/yr but Holocene slip rates are thought to be closer to the lower value.
San Jose
(ll-r-o, 75 NW)
22 2 0.50 0.50 U 6.5 0.00068 1471 13 2 0 13 0 75 315 -117.88;34.04 -117.69;34.11 Unconstrained slip rate reported by Dolan, et al (1995), based on geomorphic expression of fault.
Santa Monica
(ll-r-o, 75 N)
28 3 1.00 0.50 P-M 6.6 0.00123 816 13 2 0 13 0 75 0 -118.41;34.08 -118.69;33.99 Published slip rate (0.3mm/yr; Clark et al.,1984) is for Potrero Canyon fault, a branch of Santa Monica fault zone. Slip rate of 1mm/yr is based on 2 assumptions: 1). H:V is 1:1 and 2). slip rate for Potrero Canyon is half of entire Santa Monica fault.
Santa Ynez (west
segment)

(ll-ss)
65 7 2.00 1.00 M 6.9 0.00202 495 13 2 0 13 0 80 180 -120.31;34.51 -119.63;34.49 Slip rate is preferred left-lateral, based on offset stream channel reported by Darrow and Sylvester (1984).
Santa Ynez (east
segment)

(ll-ss)
68 7 2.00 1.00 M 7.0 0.00149 669 13 2 0 13 0 80 180 -119.63;34.49 -118.91;34.59 Slip rate is preferred left-lateral, based on offset stream channel reported by Darrow and Sylvester (1984).
Santa Susana
(r, 55 N)
27 3 5.00 2.00 P 6.6 0.00727 138 16 2 0 13 90 55 0 -118.77;34.36 -118.50;34.32 Dip-slip rate estimated by authors is composite of several published rates (Yeats, 1987; Levi & Yeats, 1993; Huftile, 1992; WGCEP, 1995).
Sierra Madre (San
Fernando)

(r, 45 N)
18 2 2.00 1.00 P 6.7 0.00100 1000 18 2 0 13 90 45 0 -118.48;34.30 -118.30;34.28 Dip-slip rate is combination of rate reported by Clark et al (1984) and estimate by authors for the Dunsmore alluvial fan (of age 2-10 ka) reported in Crook et al. (1987). Max. magnitude based on 1971 San Fernando earthquake (Wells and Coppersmith, 1994). Recurrence (about 1 ka) of San Fernando segment based on USGS (1996).
Sierra Madre
(r, 45 N)
57 6 3.00 1.00 P 7.0 0.00260 384 18 2 0 13 90 45 0 -118.29;34.28 -117.80;34.16 Dip-slip rate is combination of slip rate reported by Clark et al (1984), estimate by authors for the Dunsmore alluvial fan (of age 2-10 ka) reported in Crook et al. (1987), and slip rate reported in WGCEP (1995).
Simi-Santa Rosa
(r,60 N)
30 3 1.00 0.50 P 6.7 0.00107 933 15 2 1 14 90 60 0 -119.11;34.22 -118.80;34.29 Slip rate reported by Gonzalez and Rockwell (1991) is for Springville fault, a branch of Simi-Santa Rosa fault. Slip rate of 1mm/yr assumed in order to account for entire fault zone.
Ventura-Pitas Point
(r-ll-o, 75 N)
41 4 1.00 0.50 M 6.8 16 0.00090 1112 13 2 1 14 90 75 0 -119.55;34.31 -119.14;34.34 Focal mechanism for M 3.0 earthquake presumably on Ventura fault suggests 1:3 H:V ratio of slip. Slip rate is estimated by authors based on height of scarp across Harmon alluvial fan mapped by Sarna-Wojcicki, et al (1976) and assumed slip components.
Verdugo
(r, 45 NE)
29 3 0.50 0.50 U 6.7 0.00062 1608 18 2 0 13 90 45 45 -118.42;34.26 -118.15;34.13 Unconstrained slip rate based on report of scarps in alluvial fans (Weber, et al., 1980). fault zone may complexly join Raymond fault along Eagle Rock and San Rafael flts.
White Wolf
(r-ll-o, 60 S)
67 7 2.00 2.00 P 7.2 0.00119 839 21 2 0 18 90 60 180 -119.10;35.08 -118.48;35.39 Poorly constrained long term slip rate, based on Stein and Thatcher (1981), is suggestive of about 5mm/yr. WGCEP (1995) used slip rate of 2 mm/yr. Dip of fault based on 1952 earthquake focal mechanism and modeling by Stein and Thatcher. Max. magnitude (7.2) based on seismic moment for 1952 earthquake reported in Stein and Thatcher. Hutton and Jones (1993) reported M 7.5 for 1952 earthquake.

Los Angeles Blind Thrusts

Compton Thrust
(r, 20 NE)
39 4 1.50 1.00 P 6.8 0.00148 676 15 2 5 10 90 20 30 -118.49;33.78 -118.14;33.59 Slip rate and fault geometry reported by Shaw and Suppe (1996) and comparison with the Elysian Park fault. Model weighted 50%. End point coordinates are for surface projection of rupture plane.
Elysian Park
(r, 20 NE)
34 3 1.50 1.00 P 6.7 0.00182 549 15 2 10 15 90 20 30 -118.39;33.8 -118.08;33.64 Slip rate and fault zone geometry reported by Shaw and Suppe (1996), Bullard and Lettis (1993). Model weighted 50%. End point coordinates are for surface projection of rupture plane.
Northridge
(r, 42 S)
31 3 1.50 1.00 P 6.9 0.00122 818 22 2 5 20 90 42 180 -118.68;34.45 -118.38;34.32 Slip rate based on Yeats and Huftile (1995). End point coordinates are for surface projection of rupture plane.
  1. W — well-constrained slip rate; M — moderately constrained slip rate; P — poorly constrained slip rate; U — unconstrained slip rate.
  2. Maximum moment magnitude calculated from relationships (rupture area) derived by Wells and Coppersmith (1984).
  3. R.I. — recurrence interval.
  4. Down-dip width = (rupture bottom minus rupture top) divided by sine of dip angle.
  5. Top of rupture.
  6. Bottom of rupture.
  7. daz — dip azimuth.

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Straigraphic Code. Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.