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California Fault Parameters 

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
NORTHERN COAST RANGES
Bartlett Springs
(rl-ss) 		85 9 6.00 3.00 P 7.1 0.00458 218 15 2 0 15 180 90 0 -123.05;39.57 -122.50;38.93 Slip rate based on assumption that slip carried from Concord-Green Valley system (WGNCEP, 1996). Taylor and Swan (1986) and Swan and Taylor (1991) reported minimum slip rate of 1-2mm/yr for segment at Lk. Pillsbury, based on apparent vertical separation and plunge of slickensides.
Collayomi
(rl-ss) 		29 3 0.60 0.30 P 6.5 0.00083 1209 10 2 0 10 180 90 0 -122.86;38.99 -122.68;38.78 Slip rate based on (Clark, et al., 1984)
Garberville-
Briceland
(rl-ss) 		39 4 9.00 2.00 U 6.9 0.00454 220 12 2 0 12 180 90 0 -124.02;40.27 -123.72;39.99 Rate based on assumption that slip carried from Maacama flt (WGNCEP, 1996). Max. magnitude based on assumed 2 m slip.
Hunting Creek-
Berryessa
(rl-ss)		 60 6 6.00 3.00 U 6.9 0.00516 194 12 2 0 12 180 90 0 -122.50;38.93 -122.20;38.45 Slip rate based on assumption that slip is carried from Concord-Green Valley system (WGNCEP, 1996).
Lake Mountain
(rl-ss) 		33 3 6.00 3.00 P 6.7 0.00708 141 15 2 0 15 180 90 0 -123.46;40.28 -123.44;39.98 Slip rate based on assumption that slip is carried from Green Valley-Concord system (WGNCEP, 1996) and measurement of fault creep at Covelo (Lisowski and Prescot, 1989; M.H. Murray, written communication to J. Lienkaemper, 1996).
Maacama (south)
(rl-ss)		 41 4 9.00 2.00 P 6.9 0.00454 220 12 2 0 12 180 90 0 -123.00;38.86 -122.69;38.58 Slip rate of 9 mm/yr based on assumption that dextral slip from Hayward - Rodgers Crk. flt carried NW along Maacama zone (WGNCEP, 1996). Max. magnitude based on assumed 2 m slip.
Maacama (central)
(rl-ss) 		60 6 9.00 2.00 P 7.1 0.00454 220 12 2 0 12 180 90 0 123.29;39.34 -123.00;38.85 Flt. has creep rate of 6.9 mm/yr in Ukiah (Galehouse, 1995). 9 mm/yr slip rate based on assumption that dextral slip from Hayward - Rodgers Crk. flt carried NW along Maacama zone (WGNCEP, 1996). Max. magnitude based on assumed 2 m slip.
Maacama (north)
(rl-ss)		 81 8 9.00 2.00 P 7.1 0.00454 220 12 2 0 12 180 90 0 -123.72;39.99 -123.29;39.34 Flt. has creep rate of 7.3 mm/yr in Willits Galehouse, 1995). 9 mm/yr slip rate based on assumption that dextral slip from Hayward - Rodgers Crk. flt carried NW along Maacama zone (WGNCEP, 1996). Max. magnitude based on assumed 2 m slip.
Round Valley
(rl-ss) 		56 6 6.00 3.00 P 6.8 0.00680 147 12 2 0 12 180 90 0 -123.45;39.97 -123.05;39.57 Slip rate based on assumption that slip is carried from Green Valley-Concord system (WGNCEP, 1996) and measurement of fault creep at Covelo (Lisowski and Prescot, 1989; M.H. Murray, written communication to J. Lienkaemper, 1996).
 

NORTHWESTERN CALIFORNIA

Big Lagoon - Bald Mtn. flt zone
(r, 35 NE) 		88 9 0.50 0.50 P 7.3 0.00030 3294 23 2 0 13 90 35 45 -124.44;41.73 -123.99;41.11 Long term slip rate, based on vertical offset of Pliocene "Klamath sapprolite" and assumption that age of offset began about 1ma (McCrory, 1996).
Cascadia subduction zone
(r, 15 E)		 257 26 35.00 5.00 P 8.3 0.00667 150 58 2 5 20 90 15 90 -123.80;45.00 -123.80;40.20 Slip rate and max. mag. earthquake based on Toppozada, et al (1995). End point coordinates are for bottom of rupture plane.
Cascadia (all)
(r, 15 E) 		1029 50 35.00 5.00 P 9.0 0.00200 500 58 2 5 20 90 15 90 -126.60;50.00 -123.80;40.20 End point coordinates are for bottom of rupture plane.
Fickle Hill
(r, 35 NE)		 34 3 0.60 0.40 P 6.9 0.00056 1785 23 2 0 13 90 35 45 -124.18;40.98 -123.94;40.73 Slip rate based on Carver & Burke (1992) and McCrory (1996).
Little Salmon (onshore)
(r, 30 NE) 		34 3 5.00 3.00 M 7.0 0.00374 268 26 2 0 13 90 30 45 -124.23;40.76 -123.99;40.53 Slip rate based on Carver & Burke (1988, 1992) and assumption by authors that main trace has slip rate of 4 mm/yr and 1 mm/yr for eastern strand. Slip based on 30 degree dip.
Little Salmon (offshore)
(r, 30 NE) 		46 5 1.00 1.00 P 7.1 0.00072 1397 26 2 0 13 90 30 45 -124.64;41.00 -124.23;40.76 Poorly constrained slip rate based on vertical separation of Rio Dell equivalent strata (1 my) and base and top of Hookton Fm. (about 0.5 my) reported by McCrory (1996).
Mad River
(r, 35 NE) 		52 5 0.70 0.60 P 7.1 0.00050 1995 23 2 0 13 90 35 45 -124.23; 41.02 -123.90; 40.63 Slip rate based on Carver & Burke (1992) and assummed dip of 30 degrees.
McKinleyville
(r, 35 NE) 		48 5 0.60 0.20 M 7.0 0.00056 1785 23 2 0 13 90 35 45 -124.26;41.08 -123.89;40.74 Slip rate based on recalulation of rate by Carver & Burke (1992), with assumption that lowest terrace age is 80ka.
Mendocino fault zone
(rl-r-o) 		179 18 35.00 5.00 P 7.4 0.01996 50 15 2 15 30 180 90 0 -126.40;40.41 -124.34;40.23 Slip rate based on relative plate motion (McCrory, et al., 1995). Max. magnitude based on McCrory (p.c., April 1996).
Table Bluff
(r, 45 NE)		 49 5 0.60 0.60 P 7.0 0.00045 2235 18 2 0 13 90 45 45 -124.68;40.83 -124.18;40.65 Poorly constrained slip rate based on 700 m vertical offset of basement rocks. Age of deformation assumed to have begun about 1ma (McCrory, 1996).
Trinadad
(r, 35 NE) 		88 9 2.50 1.50 P 7.3 0.00152 659 23 2 0 13 90 35 45 -124.39;41.45 -123.84;40.79 Slip rate based on recalulation of slip rate reported by Carver & Burke (1992), with assumption that lowest terrace age is 80ka. Dip slip rate includes horizontal shortening rate from Trinidad anticline, resolved for 35 degree dipping fault (P. McCrory, p.c., 1996). Length includes offshore faults.
 

NORTHEASTERN CALIFORNIA

Cedar Mtn. - Mahogany Mtn.
(n, 60 E) 		78 8 1.00 0.50 P 6.9 0.00102 976 11 2 0 10 -90 60 90 -122.06;42.22 -121.91;41.53 Poorly constrained slip rate of 0.2mm/yr based on vertical offset of late Tioga gravels along E. Cedar Mtn. flt. reported by Bryant and Wills (1991). 1mm/yr slip rate assumed for entire fault zone, including Mahogany Mtn. flt. zone.
Gillem-Big Crack
(n, 60 E) 		32 3 1.00 0.50 P 6.6 0.00140 995 13 2 0 11 -90 60 90 -121.57;41.97 -121.59;41.68 Poorly constrained slip rate based on vertical separation of late Pleistocene (about 40ka) Mammoth Crater basalt (Donnelly-Nolan and Champion (1987).
Goose Lake
(n, 60 W) 		57 6 0.10 0.05 P 6.8 0.00011 9454 11 2 0 10 -90 60 270 -120.34;42.26 -120.19;41.79 Slip rate based on Pezzopane (1993).
Hat Creek-
McArthur-Mayfield

(n, 60 W) 		96 10 1.50 1.00 P-M 7.0 0.00134 747 11 2 0 10 -90 60 270 -121.59;41.47 -121.37;40.63 Source model assumes rupture along Hat Creek, McArthur, and Mayfield faults. Hat Creek flt. has poorly to moderately constrained slip rate based on offset of Tioga lateral moraine reported by Muffler (1994) and Sawyer (p.c. 1995). McArthur flt. has poorly constrained slip rate based on offset of 'Popcorn Cave basalt' (Page, et al, 1995). Mayfield flt. has moderate to well-constrained slip rate based on vertical offset of 10.6ka basalt and surveyed scarp profiles (Donnelly-Nolan, et al, 1990).
Honey Lake
(rl-ss) 		55 6 2.50 1.00 M-W 6.9 0.00067 1493 11 2 0 11 180 90 0 -120.51;40.34 -120.04;39.99 Slip rate based on dextral offset of Holocene fluvial terrace reported by Wills and Borchardt (1993) (1.9 0.8mm/yr) At least 4 surface rupturing events have occurred in the past 6 ka, suggesting a recurrence of about 1.5 ka. Slip rate includes assummed slip from Warm Springs fault.
Likely
(rl-ss)		 64 6 0.30 0.30 U 6.9 0.00025 3964 11 2 0 11 180 90 0 -120.73;41.34 -120.25;40.89 Unconstrained slip rate based on assumption by authors that up to 5 m of dextral offset of latest Pleistocene shorelines at northern Madeline Plains (Bryant, 1991) may go unobserved and also overall geomorphic expression of fault zone.
Surprise Valley
(n, 60 E) 		87 9 1.30 0.50 M 7.0 0.00105 951 11 2 0 10 -90 60 90 -120.14;41.88 -119.99;41.13 Slip rate base on vertical offset of Holocene alluvial fans and assumptions of fan ages based on relationship to Pleistocene Lk. Surprise (Hedel, 1980, 1984).
  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.