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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)

SANTA BARBARA CHANNEL

Anacapa-Dume
(r,-ll-o 45 N)
75 8 3.00 2.00 U 7.3 0.00189 529 28 2 0 20 90 45 0 -119.50;33.99 -118.69;33.98 Unconstrained slip rate, based on assumption by authors that fault carries 1 mm/yr sinstral slip rate from Santa Monica flt and 3.0 mm/yr dextral slip rate from Palos Verdes fault is carried as contractional slip rate.
Channel Islands
Thrust (eastern)

(r, 17N)
65 7 1.50 1.00 P 7.4 0.00070 1420 34 2 5 15 90 17 0 -119.95;33.98 -119.27;33.98 Blind thrust fault based on modeling by Shaw and Suppe (1994). Slip rate is based on deformation of 1 my old horizon and is considered poorly constrained. Model weighted 25%. End point coordinates are for top of rupture plane.
Montalvo-Oakridge
trend

(r, 28 N)
37 4 1.00 1.00 P 6.6 0.00137 730 11 2 5 10 90 28 0 -119.67;34.25 -119.28;34.25 Poolry constrained slip rate based on modeling of detachment zone by Shaw and Suppe (1994). Model weighted 25%. End point coordinates are for top of rupture plane.
North Channel Slope
(r, 45 N)
60 6 2.00 2.00 P 7.1 0.00165 605 23 2 10 20 90 26 0 -120.40;34.46 -119.67;34.40 Slip rate based on assumption that slip rates from Red Mtn.-Javon Cn. and Pitas Pt. flts transfer to N-dipping thrust. Model weighted 50%. End point coordinates are for top of rupture plane.
Oakridge (blind thrust offshore)
(r, 30 S)
37 4 3.00 3.00 P 6.9 0.00265 377 20 2 5 15 90 30 180 -119.67;34.25 -119.28;34.25 Alternative model based on Huftile and Yeats (1995). Replaces slip on eastern Channel Island Thrust and Montalvo-Oakridge trend. Model weighted 25%.
Santa Cruz Island
(ll-r-o)
50 5 1.00 0.50 M 6.8 0.00110 912 13 2 0 13 90 90 0 -120.04;34.10 -119.52;33.99 Moderately constrained Qt. slip rate (0.75mm/yr) based on offset streams incised into Stage 11 (?) terrace (Pinter, et al., 1995).
Santa Rosa Island
(ll-r-o)
57 6 1.00 0.50 M 6.9 0.00088 1130 13 2 0 13 90 90 0 -120.51;34.03 -119.91;34.02 Moderately constrained Qt. slip rate (1mm/yr) based on offset incised stream channels (Colson et al., 1995).
 

E. TRANSVERSE RANGES AND MOJAVE

Blackwater
(rl-ss)
60 6 0.60 0.40 P 6.9 0.00056 1789 13 2 0 13 180 90 0 -117.41;35.45 -117.02;35.02 Mojave slip rates based on Holocene rates reported for Homestead Vlly., Emerson, and Johnson Vlly. flts (Hecker, et al., 1993; Rubin and Sieh, 1993; Herzberg and Rockwell, 1993), similar geomorphic expression, and geodetic constraints across Mojave shear zone (about 8mm/yr).
Burnt Mtn.
(rl-ss)
20 2 0.60 0.40 P 6.4 0.00020 5000 13 2 0 13 180 90 0 -116.41;34.12 -116.38;33.95 See Blackwater fault for slip rate assumptions. Minor triggered slip associated with 1992 Landers earthquake.
Calico-Hidalgo
(rl-ss)
95 10 0.60 0.40 P 7.1 0.00020 5000 13 2 0 13 180 90 0 -116.92;34.99 -116.26;34.36 See Blackwater fault.
Cleghorn
(ll-ss)
25 3 3.00 2.00 P 6.5 0.00464 216 13 2 0 13 0 90 0 -117.46;34.31 -117.20;34.28 Slip rate based on Meisling (1984).
Eureka Peak
(rl-ss)
19 2 0.60 0.40 P 6.4 0.00020 5000 13 2 0 13 180 90 0 -116.39;34.12 -116.34;33.97 See Blackwater fault for slip rate assumptions. Triggered slip associated with 1992 Landers earthquake. April 1992 Joshua Tree earthquake swarm (M6.1) may have been along this fault zone.
Gravel Hills-Harper Lk.
(rl-ss)
66 7 0.60 0.40 P 6.9 0.00020 5000 13 2 0 13 180 90 0 -117.45;35.26 -116.92;34.87 See Blackwater fault.
Gravel Hills-Harper Lk.
(rl-ss)
66 7 0.60 0.40 P 6.9 0.00020 5000 13 2 0 13 180 90 0 -117.45;35.26 -116.92;34.87 See Blackwater fault.
Johnson Valley (northern)
(rl-ss)
36 4 0.60 0.40 P 6.7 0.00020 5000 13 2 0 13 180 90 0 -116.69;34.56 -116.45;34.32 Slip rate based on Herzberg and Rockwell (1993). Fault segment assumed to rupture independently of Landers event.
Landers
(rl-ss)
83 8 0.60 0.40 P-M 7.3 0.00020 5000 13 2 0 13 180 90 0 -116.84;34.79 -116.42;34.16 992 Landers earthquake rupture (Hauksson, et al (1993). Max. magnitude based on average 3 m slip.
Lenwood-Lockhart-
Old Woman Springs
(rl-ss)
149 15 0.60 0.40 P 7.3 0.00020 5000 13 2 0 13 180 90 0 -117.76;35.22 -116.64;34.35 See Blackwater fault.
North Frontal Fault zone (western)
(r, 45 S)
50 5 1.00 0.50 P 7.0 0.00076 1314 18 2 0 13 90 45 180 -117.27;34.32 -116.85;34.37 Reported slip rate of 1.2 mm/yr for Sky High Ranch fault, a RLSS segment of fault zone (Meisling, 1984). Other reported slip rates range between 0.1 and 1.3 mm/yr.
North Frontal Fault zone (eastern)
(r, 45 S)
27 3 0.50 0.25 U 6.7 0.00058 1727 18 2 0 13 90 45 180 -116.80;34.34 -116.53;34.31 Flt. zone east of intersection with Helendale flt. Unconstrained slip rate based on assumption that some slip transferred to NW-striking flts.
Pinto Mountain
(ll-ss)
73 7 2.50 2.00 P 7.0 0.00201 499 13 2 0 13 0 90 0 -116.72;34.06 -115.97;34.11 Long term slip rate based on Anderson (1979). Reported slip rates range from 0.3-5.3.
Pisgah-Bullion Mtn.-
Mesquite Lk.

(rl-ss)
88 9 0.60 0.40 P 7.1 0.00020 5000 13 2 0 13 180 90 0 -116.49;34.82 -116.00;34.14 Slip rate based on rl offset of drainage developed on Sunshine lava flow (Hart, 1987).
S. Emerson-Copper
Mtn.

(rl-ss)
54 5 0.60 0.40 P 6.9 0.00020 5000 13 2 0 13 180 90 0 -116.54;34.53 -116.18;34.16 Slip rate based on Rubin and Sieh (1993). Fault segment assumed to rupture independently of Landers event.
  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.