U.S. DEPARTMENT OF THE INTERIOR 

U.S. GEOLOGICAL SURVEY 

Documentation of changes in fault parameters 

for the 2002 National Seismic Hazard Maps— 

Conterminous United States except California 

by

Kathleen M. Haller1, Russell L. Wheeler1, Kenneth S. Rukstales1 

U.S. Geological Survey 

Open-File Report 02-467 

This report is preliminary and has not been reviewed for conformity with U.S. Geological 

Survey editorial standards (or with the North American Stratigraphic Code). Any use of 

trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

1 Denver, Colorado 
CONTENTS

1. INTRODUCTION ............................................................................................................................................. 1


2. OVERVIEW OF CHANGES............................................................................................................................ 1


2.1. SLIP RATES.............................................................................................................................................. 1


2.2. FAULT NAMES......................................................................................................................................... 2


2.3. FAULT TRACES ....................................................................................................................................... 5


3. CONTACTS FOR QUESTIONS...................................................................................................................... 5


4. CHANGES BY STATE..................................................................................................................................... 5


4.1. ARIZONA................................................................................................................................................. 6


4.2. CALIFORNIA............................................................................................................................................ 6


4.3. COLORADO ............................................................................................................................................. 6


4.4. IDAHO ..................................................................................................................................................... 7


4.5. MONTANA............................................................................................................................................... 8


4.6. NEVADA.................................................................................................................................................. 9


4.7. NEW MEXICO ....................................................................................................................................... 16


4.8. OREGON................................................................................................................................................ 17


4.9. TEXAS................................................................................................................................................... 21


4.10. UTAH .................................................................................................................................................... 23


4.11. WASHINGTON....................................................................................................................................... 24


4.12. WYOMING............................................................................................................................................. 25


5. 2002 FAULT PARAMETERS........................................................................................................................ 26


6. REFERENCES................................................................................................................................................. 26


TABLES

TABLE 1. ............................................................................................................................................................... 2


TABLE 2. ................................................................................................................................................... see p. 26

DOCUMENTATION OF CHANGES IN FAULT PARAMETERS 

FOR THE 2002 NATIONAL SEISMIC-HAZARD MAPS— 

CONTERMINOUS UNITED STATES EXCEPT CALIFORNIA 

by Kathleen M. Haller, Russell L. Wheeler, Kenneth Rukstales 

1. INTRODUCTION 

This document defines the changes in fault parameters between the 1996 and 2002 

versions of the national seismic hazard maps. We note faults that have been added or 

deleted for the 2002 maps, name changes, and changes in assigned slip rate. We do not 

describe here faults where the slip rates for the 2002 maps are essentially the same as 

those used in 1996. The fault parameters used in 2002 were derived from descriptions in 

the Quaternary fault and fold database for the U.S., a digital compilation of available 

information documenting Quaternary surface deformation nationwide. The compilation 

and database is being organized and overseen by M.N. Machette, K.M. Haller, and 

numerous colleagues including personnel of state geological surveys. Published parts of 

the database (Collins and others, 1996; Machette and others, 1998; Pearthree, 1998; 

Widmann and others, 1998; Black and others, 2000; Crone and Wheeler, 2000; Haller 

and others, 2000; Machette and others, 2001) and similar products in progress for 

Oregon, Washington, and Idaho were used as the primary input for revising slip rates for 

2002. 

We frequently refer to the Web-based documentation of faults and their parameters that 

were used in 1996. That documentation is at http://geohazards.cr.usgs.gov/eq/index.html (as 

of 10/22/02). Parameters for California faults were calculated in cooperation with the 

California Geological Survey and are documented separately. 

2. OVERVIEW OF CHANGES 

2.1. Slip rates 

All slip rates given for normal or reverse faults are vertical rates, because the most 

common paleoseismological data available to calculate rates for dip-slip faults are uplift 

rates, scarp heights, or vertical surface offsets. For dip-slip faults, the vertical rates are 

converted to fault parallel rates by using the assigned dip (generally 60 degrees) prior to 

recurrence computation. 

Most of the slip rates in the 1996 and 2002 maps are based on sparse data of variable 

quality and poorly known uncertainties. Commonly, rates change with the addition of 

new data. Many of the faults depicted here are characterized by sparse old information 

that is not up to modern standards. Few faults have been trenched at more than two sites, 

or have trenches deep enough to reveal the records of more than two or three surface 

faulting events. Results from these few well-studied faults demonstrate that slip rates can 

vary widely through time at a site and between sites along a single fault. 

1
2.2. Fault names 

Some 1996 fault names have been modified in 2002 to correspond to names regarded to 

be in common usage in the Quaternary fault and fold database for the United States. To 

facilitate comparisons between fault parameters used in 1996 and 2002, we provide the 

following list of name changes. A few name changes occurred because new data shows 

that a fault as portrayed in 1996 is actually two or that two or more 1996 faults are 

actually one. However, most name changes occurred because many of the 1996 names 

were taken from informally published contract reports. In contrast, all the 2002 names are 

based on exhaustive literature searches that are summarized in the Quaternary fault and 

fold database for the United States. We judge that the database uses fault names that are 

most likely to conform to local and long-standing usage. Accordingly, if a 1996 name 

differs from the name used in the database, we use the latter. 

Table 1. Changes in fault name listed by State. 

STATE 1996 FAULT NAME 2002 FAULT NAME 

Colorado Sangre de Cristo fault Northern Sangre de Cristo fault 

Sawatch Range fault Southern Sawatch fault 

Nevada Bettles Well fault Bettles Well-Petrified Springs fault 

Clan Alpine Mountains fault Middlegate fault zone 

Coal Valley fault Golden Gate fault 

Cortez Mountains fault 1, Cortez 

Mountains fault 2 

Cortez Mountain fault zone 

Crystal Springs fault Hiko fault zone 

Dry Valley fault Dry Valley-Smoke Creek Ranch fault 

zone 

Eastern Edwards Creek Valley 

fault 1 

Buffalo Creek fault zone 

Eastern Edwards Creek Valley 

fault 2 

Eastern Edwards Creek Valley fault 

zone 

Eastern Osgood Mountains fault 

1 

Eastern Osgood Mountains fault zone 

Eastern Osgood Mountains fault 

2 

Eastern Osgood Mountains piedmont 

fault 

Fairview Peak fault Fairview fault zone 

Huntoon Valley fault 1 and 3 faults in Excelsior Mountains (#1316) 

Huntoon Valley fault 2 unnamed faults (#1303) 

Huntoon Valley fault 4 unnamed faults (#1302) 

Independence Valley fault 1, 

Independence Valley fault 2 

Independence Valley fault zone 

Indian Valley fault Southwest Reese River Valley fault 

(part of) 

Jackson Mountains fault 1, 

Jackson Mountains fault 2 

Jackson Mountains fault zone 

2
Table 1 (cont). Changes in fault name listed by State. 

STATE 1996 FAULT NAME 2002 FAULT NAME 

Nevada 

(cont.) 

Jersey Valley fault 1, 

Jersey Valley fault 2 

Jersey Valley fault zone 

Liberty fault Crescent Dunes fault 

Montana Mountains fault Montana Mountains/Desert Valley fault 

zone 

Mount Rose fault 2 Little Valley fault 

Northeast Long Valley fault Warner Valley faults (east) 

Northern Pine Forest Range fault Eastern Pine Forest Range fault zone 

North Pahranagat Range fault Mount Irish Range fault 

Peterson Mountain fault 1, 

Peterson Mountain fault 2 

Petersen Mountain fault 

Pueblo Mountains fault Steens fault zone (part of) 

Pumpernickel Valley fault Edna Mountain fault 

Rattlesnake Flat fault faults in southern Garfield Hills 

Ruby Mountains fault 1 Ruby Mountains fault zone, northern 

section 

Ruby Mountains fault 2 Ruby Mountains fault zone, southern 

section 

Ruby Mountains fault 3 Northern Huntington Valley fault 

Selenite Range fault Selenite Range fault zone, and 

Nightingale Mountains fault zone 

Southeast Sheep Creek Range 

fault 

Sheep Creek Range southeastern fault 

Southwestern Delamar 

Mountains Fault 

Coyote Spring fault 

Stingaree Valley fault West Gate fault 

Sweetwater Flat fault Smith Valley fault (part of) 

Unnamed fault Ione Valley fault (part of) 

Wassuk Range fault 1, 

Wassuk Range fault 2 

Wassuk Range fault zone 

Western Carico Lake Valley 

fault 

Carico Lake Valley fault system (part 

of) 

Western Edwards Creek Valley 

fault 

Clan Alpine fault zone 

Western Humboldt Range fault 

1, Western Humboldt Range 

fault 2 

Western Humboldt Range fault zone 

Whirlwind Valley fault Beowawe fault 

Western Smoke Creek Desert 

fault 1, Western Smoke Creek 

Desert fault 2 

Bonham Ranch fault zone 

3
Table 1 (cont). Changes in fault name listed by State. 

STATE 1996 FAULT NAME 2002 FAULT NAME 

New 

Mexico 

Fault of Black Mesa Black Mesa fault zone 

Sangre de Cristo fault Southern Sangre de Cristo fault zone 

West Mesa fault County Dump fault, 

Zia fault 

Oregon Brownlee fault Pine Valley graben fault system (also 

includes the 1996 Halfway and Posey 

Valley faults) 

East Chemult graben – Walker 

Rim fault 

Chemult graben fault system (east) 

East Klamath graben fault Klamath graben fault system (east) 

(also includes the 1996 South Klamath 

graben zone) 

East Warner Valley fault, north, 

and East Warner Valley fault, 

south 

Warner Valley faults (east) 

Eastern Alvord graben fault Tule Springs Rims faults 

Halfway fault Pine Valley graben fault system (also 

includes the 1996 Brownlee and Posey 

Valley faults) 

Mill Creek fault Turner and Mill Creek faults 

Netarts Bay fault Happy Camp fault 

Posey Valley fault Pine Valley graben fault system (also 

includes the 1996 Halfway and 

Brownlee faults) 

Santa Rosa-Owyhee RiverOregon Canyon fault zone Santa Rosa Range fault system 

South Klamath graben zone Klamath graben fault system (east) 

(also includes the 1996 East Klamath 

graben fault) 

Southeast Newberry, Crack-inthe-Ground fault Southeast Newberry fault zone 

Tumalo-Black Butte faults Metolius fault zone 

West Chemult graben – Walker 

Rim fault 

Chemult graben fault system (west) 

West Klamath Lake fault Klamath graben fault system (west) 

West Warner Valley fault Warner Valley faults (west) 

Winchester fault South Slough thrust and reverse faults 

Winter Ridge–Slide Mountain 

fault 

Winter Rim fault system 

4
Table 1 (cont). Changes in fault name listed by State. 

STATE 1996 FAULT NAME 2002 FAULT NAME 

Texas East Baylor Mountain fault East Baylor Mountain-Carrizo 

Mountain fault 

Sierra Diablo fault East Sierra Diablo fault (combined in 

1996 with the East Flat Top Mountain 

and North Sierra Diablo faults) 

Utah East Great Salt Lake fault 1 East Great Salt Lake fault zone, 

Promontory section 

East Great Salt Lake fault 2 East Great Salt Lake fault zone, 

Fremont Island section; and 

East Great Salt Lake fault zone, 

Antelope Island section 

East Joes Valley fault Joes Valley fault zone east fault 

Joes Valley fault Joes Valley fault zone west fault 

Wyoming East Yellowstone River fault, 

and West Yellowstone River 

fault 

Upper Yellowstone Valley faults 

Factory Hill fault East Mount Sheridan faults 

Star Valley fault Grand Valley fault 

2.3. Fault traces 

Most traces were simplified from those depicted in the Quaternary fault and fold database 

for the United States. For the few faults that are not included in that database, we used the 

1996 traces with appropriate modifications. 

3. CONTACTS FOR QUESTIONS 

Questions and comments about the fault parameters should be directed to Kathy Haller 

(haller@usgs.gov) or Rus Wheeler (wheeler@usgs.gov). 

4. CHANGES BY STATE 

This section describes changes in assigned slip rate for individual faults. Faults are listed 

alphabetically by state. Each paragraph explains changes from the 1996 source 

parameters to produce the 2002 map. We do not report on those faults for which the slip 

rates for the 2002 maps are essentially the same as those used in 1996. 

The first line of each paragraph lists (1) the 2002 fault name in capitals and 1996 name in 

mixed case if the two names are different, (2) the identification number of the fault in the 

Quaternary fault and fold database for the United States, (3) the 1996, and (4) 2002 slip 

rates. If the fault was not included in the 1996 maps but was added for the 2002 maps, 

“added for 2002 ” appears in the first line instead of a 1996 slip rate. If a fault described 

5
in this section crosses a state border, it is described in the listing under the state that 

contains most of its length and cross-referenced under the other state. 

4.1. Arizona 

ALGODONES FAULT ZONE, #944, added for 2002, 0.15 mm/yr (2002).

Scarps are 7-15 m high on Upper Mesa deposits, which soil development indicates to be

50-100 k.y. old (Woodward-McNeil & Associates, 1974). The midpoints of the offset and

age ranges yield the assigned slip rate.

BIG CHINO FAULT, #951, 0.09 mm/yr (1996), 0.083 mm/yr (2002).

The assigned slip rate is based on upper Pleistocene (estimated 80-100 ka) alluvial

deposits that trenching showed to be offset vertically 7-8 m (Euge and others, 1992).

DUTCHMAN DRAW FAULT, #1003, added for 2002, 0.075 mm/yr (2002).

The assigned slip rate is based on an early Quaternary basalt, dated at 1.4 ± 0.3 Ma

(Wenrich and others, 1995) that is displaced approximately 100 m. From these data, P.A.

Pearthree (written commun., 2002) calculated a slip rate of 0.06-0.09 mm/yr. We

assigned the average of this range for 2002.

HURRICANE FAULT ZONE, #998, 0.4 mm/yr (1996); 0.1 mm/yr—northern (#998ab)

and southern (#998ef) parts, 0.2 mm/yr—central (#998cd) part (2002).

The assigned 2002 slip rates are based on recent paleoseismologic investigations (Stenner

and others, 1999; Lund and others, 2001; Amoroso and others, 2002). None of the new

late Quaternary data suggests a rate as high as that used in 1996, which was based on a

long term rate from Hamblin and others (1981). The central part of the fault appears to be

characterized by a higher slip rate than the ends based on the lateral continuity of scarps

on alluvium. The highest value of the late Quaternary single-event rates reported by Lund

and others (2001, p. 35) from Cottonwood Canyon is 0.3 mm/yr and considered to be

larger than the characteristic late Quaternary rate for the fault.

SEVIER/TOROWEAP FAULT ZONE, #997, 0.36 mm/yr (1996), 0.36 mm/yr—northern

(#997a) part, 0.16 mm/yr—southern (#997bcd) part (2002).

The assigned slip rate for the southern part of the fault is the average rate obtained from

the data presented by Jackson (1990), who reports that 25-100 ka deposits are offset 6.5 

m. The slip rate for the northern part of the fault remains unchanged from 1996 and is 

from data presented by Anderson and Christenson (1989). 

4.2. California 

Changes for California faults are described in separate documentation. 

4.3. Colorado 

PONCHA PASS FAULT, #2312, 0.11 mm/yr (1996), excluded for 2002.

The Quaternary activity attributed to the Poncha Pass fault in 1996 actually occurred on a

nearby fault (Colman, 1985). The NW-striking, 34-km-long Poncha Pass fault appears on

at least one pre-1996 compilation map. However, the Quaternary offset in question

6
occurred on a 6-km-long, unnamed fault that parallels the Poncha Pass fault less than 5

km to the northeast. The short fault is the unnamed fault of Missouri Park, of Widmann

and others (1998). The 1996 maps included only faults long enough to contain the rupture

zone of an earthquake of Mw 6.0 or larger (Frankel and others, 1996 p. 19) and the 6-kmlong fault is too short (Wells and Coppersmith, 1994). In addition, the age of the surface

that was offset by the short fault is known but the amount of offset is not reported, so no

slip rate can be calculated.

SOUTHERN SAWATCH FAULT, Sawatch Range fault (1996), #2308b, 0.12 mm/yr

(1996), 0.062 mm/yr (2002).

The 1996 rate was derived from 3 km of suggested offset of Neogene deposits (24 Ma).

The 2002 slip rate is based on data from Ostenaa and others (1981) that suggests the

presence of scarps 8-10 m high on Bull Lake-equivalent deposits (160-130 ka).

4.4. Idaho 

BEAVERHEAD FAULT, #603, 0.3 mm/yr (1996), 0.12 mm/yr (2002).

The slip rate assigned in 1996 was based on the assertion by Scott and others (1985) that

the rate for the central part of the Beaverhead fault might be similar to that of the central

part of the Lost River fault (i.e., 0.3 mm/yr). More recent, fault specific geomorphic

studies suggest that the slip rate for the Beaverhead fault should be slower. Scarp profiles

of multiple-earthquake scarps on early Pinedale-equivalent (25-30 ka) surfaces show

vertical surface offsets at six sites on two of the central segments of the fault (Haller,

1988) that suggest an average of 0.12 mm/yr.

CENTENNIAL FAULT, #643, 1.3 mm/yr (1996), 0.9 mm/yr (2002).

The slip rate assigned in 1996 is from Pierce and Morgan (1992), who report this

maximum slip rate for the eastern and central parts of the fault based on as much as 20 m

of offset of 15 ka deposits from data of Witkind (1975). There is considerable uncertainty

in the above age assignment, and the actual late Quaternary slip rate may be 10% of the

published value. The assigned rate for the 2002 maps is based on long-term slip data

reported by Sonderegger and others (1982), in which they indicate that the 2-Ma

Huckleberry Ridge Tuff is offset 1.5-1.8 km.

LEMHI FAULT, #602, 0.3 mm/yr (1996), 0.22 mm/yr (2002).

The slip rate assigned in 1996 was based on the assertion by Scott and others (1985) that

the rate for the central part of the Lemhi fault might be similar to that of the central part

of the Lost River fault (i.e., 0.3 mm/yr). More recent, fault specific trenching and

geomorphic studies suggest that the slip rate for the Lemhi fault should be slower. Scarp

profiles of multiple-event scarps by Haller (1988) suggest slip rates of 0.18 mm/yr, 0.28

mm/yr, and 0.086 mm/yr. Trenching by Baltzer (1990) suggests a slip rate of 0.17

mm/yr. Trenching at two sites by Hemphill-Haley and others (1992) indicates a slip rate

of 0.27 mm/yr and 0.32 mm/yr, respectively. The average of these is represented by the

assigned slip rate.

LOST RIVER FAULT, #601, 0.24 mm/yr (1996), 0.15 mm/yr (2002).

The 1996 rate was based largely on 3.5-4.5 m of post-15-ka offset on a single scarp along

the central Lost River fault (Scott and others, 1985). The 2002 assigned slip rate is the

7
average of published slip rates from two of the central sections of the fault. Specifically,

trenching on the Thousand Springs section showed that 2.1 m of vertical offset in 1983

released strain that had been accumulating since 10-11 ka, for a slip rate of 0.21 mm/yr

(Vincent, 1995). Trenching on the Pass Creek section showed 13.1-18.1 m of vertical

offset of a 140- to 220-ka surface, for a slip rate of 0.06-0.13 mm/yr (Olig and others,

1995); their preferred rate is 0.095 mm/yr.

MADISON FAULT, #655, 0.6 mm/yr (1996), 0.4 mm/yr (2002).

The assigned slip rate is based on reconnaissance studies by Lundstrom (1986) and

Mathieson (1983); both report a slip rate of 0.4 mm/yr for the late Pleistocene. More

recent studies by Ruleman (2002) suggest a range of similar slip rates that average to 0.4

mm/yr.

SQUAW CREEK FAULT, #632, 0.15 mm/yr (1996), 0.1 mm/yr (2002).

The assigned slip rate is from Geomatrix Consultants, Inc. (1995).

4.5. Montana 

BLACKTAIL FAULT, #644, 0.042 mm/yr (1996), 0.03 mm/yr (2002).

The assigned rate is based on the average value from data presented by Stickney and

Bartholomew (1987) that suggest there is 4-5 m of offset of inferred upper (<150-ka)

Quaternary deposits.

CENTENNIAL FAULT, #643, 1.3 mm/yr (1996), 0.9 mm/yr (2002).

The slip rate assigned in 1996 is from Pierce and Morgan (1992), who report this

maximum slip rate for the eastern and central parts of the fault based on as much as 20 m

of offset of 15 ka deposits from data of Witkind (1975). There is considerable uncertainty

in the above age assignment, and the actual late Quaternary slip rate may be 10% of the

published value. The assigned rate for the 2002 maps is based on long-term slip data

reported by Sonderegger and others (1982), in which they indicate that the 2-Ma

Huckleberry Ridge Tuff is offset 1.5-1.8 km.

GEORGIA GULCH FAULT, #667, 0.07 mm/yr (1996), 0.031 mm/yr (2002).

The assigned slip rate is based on 4 m of offset of late Pleistocene deposits (Stickney and

Bartholomew, 1987). The assumed age of the offset deposits is 130 k.y.

MADISON FAULT, #655, 0.6 mm/yr (1996), 0.4 mm/yr (2002).

The assigned slip rate is based on reconnaissance studies by Lundstrom (1986) and

Mathieson (1983); both report a slip rate of 0.4 mm/yr for the late Pleistocene. More

recent studies by Ruleman (2002) suggest a range of similar slip rates that average to 0.4

mm/yr.

MISSION FAULT, #699, 0.75 mm/yr (1996), 0.32 mm/yr (2002).

The assigned slip rate is based on data from the North Crow and Marsh Creek sites of

Ostenaa and others (1990). They document 6-7 m of offset at the North Crow site in the

past 15-19 k.y. and 4 m of offset at the Marsh Creek site in the same time interval. The

slip rate is the average of the four maximum and minimum rates that can be calculated

from the presented data.

8
SWEETWATER FAULT, #645, 0.06 mm/yr (1996), 0.04 mm/yr (2002).

The assigned slip rate is lower than the 1996 rate because the age of the Timber Butte

basalt has recently been revised from 4 Ma to 6 Ma (Kreps and others, 1992). Both slip

rate calculations use the 250 m of offset documented by Stickney and Bartholomew

(1987).

THOMPSON VALLEY FAULT, #696, 0.1 mm/yr (1996), 0.08 mm/yr (2002).

The assigned slip rate is based on data presented by Ostenaa and others (1990). They

report that early to mid-Wisconsinan surfaces are offset 6.4 m. The assumed age of the

surface is 60-130 ka, and the assigned rate is the average of the maximum and minimum

rates calculated from these data.

4.6. Nevada 

There are several hundred known or suspected Quaternary faults in the State of Nevada;

however, there are few data on most of them. The highest quality data are from detailed

studies that provide the fault-specific information necessary to capture reasonable sliprate values; however, few of the faults in the state have been studied in this detail. Some

of the other faults are characterized in a regional assessment by dePolo (1998). He

developed a reconnaissance methodology that estimates the maximum slip rate based on

empirical relations between slip rate and the height of basal fault facets found along the

range front. For use in separate sensitivity studies that are planned to follow publication

of the 2002 maps, we have incorporated his assigned value as a maximum slip rate

because his assigned slip rate is based on the highest basal facet found along the fault.

Most of the faults in the 1996 maps were included according to the preliminary work of

dePolo (1996, written commun.). We compared the rates assigned in 1996 with the later

definitive work (dePolo, 1998) and made appropriate adjustments to assign the 2002 slip

rates.

ANTELOPE RANGE-KINGSLEY MOUNTAINS FAULT ZONE, #1261, 0.1 mm/yr

(1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

BARE MOUNTAIN FAULT, #1079, added in 2002, 0.008 mm/yr (2002).

Anderson and Klinger (1996) cite the above slip rate based on trenching at one site and

reconnaissance of the rest of the fault.

BENTON SPRING FAULT, #1320, 0.1 mm/yr (1996), 0.26 mm/yr (2002).

Bell (1995) indicates the slip rate on this fault is 0.13-0.4 mm/yr. The average of these

values is assigned here.

BLACK ROCK FAULT ZONE, #1485, 0.1 mm/yr (1996), 0.19 mm/yr (2002).

The assigned slip rate is based on 4 m of offset of a tephra bed thought to be 18-25 ka

(Dodge, 1982).

9
BLOODY RUN HILLS FAULT, #1509, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

BONHAM RANCH FAULT ZONE, Western Smoke Creek Desert fault 1 (1996), #1601,

0.1 mm/yr (1996), 0.2 mm/yr (2002).

The Quaternary fault and fold database for the United States shows that this fault was

assigned to the 0.2-1.0 mm/yr slip-rate category based on the published slip rate of Weick

(1990), who estimated a maximum Holocene vertical slip rate of about 0.7 mm/yr from

3.5 m (multiple events) of vertical separation of sediment estimated to be about 5 ka.

However, the maximum age of the deposits is not convincingly demonstrated and may be

as old as 12 ka. The assigned slip rate reflects the uncertainty in the data quality.

BUTTE MOUNTAINS FAULT ZONE, #1277, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

CALIFORNIA WASH FAULT, #1118, 0.1 mm/yr (1996), 0.28 mm/yr (2002).

dePolo (1998) assigned a preferred vertical slip rate of 0.28 mm/yr based on "known"

data, and dePolo and Anderson (2000) repeated the value. However, the data that

constrain this slip rate is not documented, as are similar data for other faults used as

calibration points in this model.

CARSON RANGE FAULT (also known as the Genoa fault), #1285, 1 mm/yr (1996), 2

mm/yr (2002).

The assigned slip rate is consistent with trenching data presented by Ramelli and others

(1994). They determined that the recurrence interval between the last events was 0.6-1.72

k.y. The multiple-event scarp is 5-6 m high; thus, a slip rate of 2 mm/yr is reasonable.

COYOTE SPRING FAULT, Southwestern Delamar Mountains fault (1996), #1121, 0.1

mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

CRESENT DUNES FAULT, Liberty fault (1996), #1340, 0.1 mm/yr (1996), 0.01 mm/yr

(2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

10
DRY LAKE FAULT, #1124, added for 2002, 0.008 (2002)

This fault was added in 2002 based on dePolo (1998 #2845) who calculated a preferred

vertical slip rate of 0.008 mm/yr based on offset of 4.4 m across a graben north of Seven

Oaks Spring. The age of the offset deposit is assumed to be 550 k.y.

EASTERN BILK CREEK MOUNTAINS FAULT ZONE, #1496, 0.1 mm/yr (1996),

0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

EASTERN OSGOOD MOUNTAINS FAULT ZONE, Eastern Osgood Mountains fault 1

(1996), #1523, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

EASTERN OSGOOD MOUNTAINS PIEDMONT FAULT, Eastern Osgood Mountains

fault 2 (1996), #1531, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

EASTERN TUSCARORA MOUNTAINS FAULT ZONE, #1554, 0.1 mm/yr (1996),

0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

EMIGRANT PEAK FAULT ZONE, #1329, 1 mm/yr (1996), 0.76 mm/yr (2002).

The slip rate used in 1996 was based on dePolo (1996, written commun.). The assigned

slip rate used here is from dePolo (1998) and dePolo and Anderson (2000) and is based

on the observed offset reported by Reheis (1991) of 38 m and the inferred age of the

offset deposit of 50 ka.

FRENCHMAN MOUNTAIN FAULT, #1117, added for 2002, 0.015 mm/yr (2002).

This fault was added in 2002 based on dePolo (1998 #2845), who calculated a vertical

slip rate of 0.015 mm/yr for the fault based on 7.5 m of offset of a deposit estimated to be

500 ka.

GOLDEN GATE FAULT, Coal Valley fault (1996), #1393, 0.1 mm/yr (1996), 0.01

mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

11
dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

GRANITE SPRINGS VALLEY FAULT ZONE, #1622, 0.5 mm/yr (1996), 0.2 mm/yr

(2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 0.506 mm/yr. Thus the slip rate used here is appropriately reassigned.

HIKO FAULT ZONE, Crystal Springs fault (1996), #1130, 0.1 mm/yr (1996), 0.01

mm/yr (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, the slip rate subsequently assigned by dePolo (1998) was 0.01

mm/yr based on the presence of scarps on alluvium but the absence of basal fault facets.

The published value will be used herein.

INDIAN HILLS.FAULT, #1652, added in 2002, 0.1 mm/yr (2002).

We added this fault in 2002 based on slip rate assigned by dePolo (1998).

JAKES VALLEY FAULT ZONE, #1223, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

KANE SPRING WASH FAULT, #1123, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). However, the slip rate subsequently assigned by

dePolo (1998) was 0.01 mm/yr based on the presence of scarps on alluvium but the

absence of basal fault facets. The published value will be used herein.

KAWICH-HOT CREEK RANGES FAULT ZONE, #1355, 0.3 mm/yr (1996), 0.2 mm/yr

(2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 0.525 mm/yr. Thus the slip rate used here is appropriately reassigned.

KINGS CANYON FAULT ZONE (northern part of the Carson Range fault in 1996),

#1654, 0.2 mm/yr (2002)

In 1996, this fault was depicted as part of the Carson Range fault and was assigned a slip

rate of 1 mm/yr. dePolo (1998), however, depicts it as a separate fault with a lower slip

rate; thus the reduction in slip rate here.

LITTLE VALLEY FAULT, Mount Rose fault 2 (1996), #1648, 0.1 mm/yr (1996), 0.2

mm/yr (2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 0.488 mm/yr. Thus the slip rate used here is appropriately increased.

12
LONE MOUNTAIN FAULT ZONE, #1338, 0.1 mm/yr (1996), 0.13 mm/yr (2002).

The assigned slip rate was calculated by dePolo (1998) based on field data from Yount

(1997, written comm., as reported in dePolo, 1998). The slip rate is derived from offset

across a 3.2-m-high scarp (presumably a multiple-event scarp) on a latest Pleistocene (15

to 30 ka) fluvial terrace along the fault west of Lone Mountain. DePolo (1998) and

dePolo and Anderson (2000) calculated a preferred vertical slip rate of 0.13 mm/yr (using

a preferred vertical offset of 2.9 m from Yount's original data) and preferred age of the

deposit of 22.5 k.y.

MARYS MOUNTAIN FAULT, #1154, 0.1 mm/yr (1996), 0.001 mm/yr (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, the slip rate subsequently assigned by dePolo (1998) was 0.001

mm/yr based on the absence of scarps on alluvium and basal fault facets. The published

value is used herein.

MCGEE MOUNTAIN FAULT ZONE, #1488, 0.1 mm/yr (1996), 0.01 mm/yr (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, the slip rate subsequently assigned by dePolo (1998) was 0.01

mm/yr based on the presence of scarps on alluvium but the absence of basal fault facets.

The published vaulue is used herein.

MOUNT IRISH RANGE FAULT, North Pahranagat Range fault (1996), #1738, 0.1

mm/yr (1996), 0.01 mm/yr (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, the slip rate subsequently assigned by dePolo (1998) was 0.01

mm/yr based on the presence of scarps on alluvium but the absence of basal fault facets.

The published vaulue is used herein.

MOUNT ROSE FAULT ZONE, #1647, 0.1 mm/yr (1996), 1.5 mm/yr (2002).

The assigned slip rate is provided by Ramelli and dePolo (1997) who estimated a range

of late Holocene slip rates of 1.1-3.8 mm/yr and tentatively preferred a slip rate of about

1.5 mm/yr, based on trench results from near Ophir Creek.

PENOYER FAULT, #1132, added for 2002, 0.016 mm/yr (2002).

This fault was added in 2002 based on dePolo (1998) and dePolo and Anderson (2000).

Their preferred vertical slip rate of 0.016 mm/yr was based on vertical offset of 5.9 m of

an uplifted alluvial fan estimated to be 375 ka.

PETERSEN MOUNTAIN FAULT 2 part of #1640, 0.1 mm/yr (1996), 0.05 mm/yr

(2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). The 2002 slip rate is reduced based on the relative

values for this and the adjacent Petersen Mountain fault assigned by dePolo (1998).

PYRAMID LAKE FAULT ZONE, #1669, 0.5 mm/yr (1996), 2 mm/yr (2002).

Briggs (2002) indicates that post-Lahonton (13 ka) channels and ridges are offset 27-33

m by the Pyramid Lake fault zone.

13
RAILROAD VALLEY FAULT ZONE, #1380, 0.1 mm/yr (1996), 0.07 mm/yr (2002).

This fault was assigned a slip rate of 0.1 mm/yr in 1996 based on preliminary data from

dePolo (1996, written commun.). The 2002 slip rate is from dePolo (1998) and dePolo

and Anderson (2000) and is based on the preferred value of an observed offset of 14 m

and inferred age of the offset deposit of 200 ka. These data yield a slip rate substantially

higher than the 0.01 mm/yr that is reported in Appendix E of dePolo (1998), based on slip

rate-basal facet relations. The higher rate is retained here.

RAINBOW MOUNTAIN FAULT ZONE, #1679, 0.1 mm/yr (1996), 0.15 mm/yr (2002).

The assigned slip rate is based on the amount of slip reported for the last two events (1.3-

1.8 m) and the length of the appropriate time interval (between 11.8-14.5 ka and the

present) as reported by Bell and others (2001). These data yield slip rates of 0.09-0.15

mm/yr. The maximum of these rates is assigned for 2002 because neither includes a

component of lateral slip that is known to have occurred at least in the historical event.

RUBY MOUNTAINS FAULT ZONE, NORTHERN SECTION, Ruby Mountains fault 1

(1996), #1573a, 0.5 mm/yr (1996), 0.28 mm/yr (2002).

The slip rate used in 1996 was based on dePolo (1996, written commun.). The slip rate

used here is from dePolo (1998) and dePolo and Anderson (2000) and is based on the

observed offset of 20.8 m and inferred age of the offset deposit of 74 ka (Willoughby,

1997).

RUBY MOUNTAINS FAULT ZONE, SOUTHERN SECTION, Ruby Mountains fault 2

(1996), #1573b, 0.5 mm/yr (1996), 0.28 mm/yr (2002).

The slip rate used in 1996 was based on dePolo (1996, written commun.). The slip rate

used here is from dePolo (1998) and dePolo and Anderson (2000) and is based on the

observed offset of 20.8 m and inferred age of the offset deposit of 74 ka (Willoughby,

1997).

RUBY VALLEY FAULT ZONE, #1718, 0.4 mm/yr (1996), 0.1 mm/yr (2002).

The assigned slip rate is reduced to 0.1 mm/yr based on the lack of evidence pointing to

multiple latest Pleistocene surface-rupturing events. Mapping by Dohrenwend and others

(1991) indicates that the youngest scarps formed in the late Pleistocene (<130 ka).

SAN EMIDIO FAULT ZONE, #1613, 0.1 mm/yr (1996), 0.2 mm/yr (2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 0.419 mm/yr. Thus, the slip rate used here is appropriately increased.

SANTA ROSA RANGE FAULT SYSTEM, Santa Rosa-Owyhee River-Oregon Canyon

fault zone (1996), #1508, 0.75 mm/yr (1996), 0.13 mm/yr (2002).

The assigned 2002 slip rate is based on the reported minimum rate of 0.01-0.13 mm/yr

reflecting the most recent interval of faulting (Narwold, 1999; 2000). These slip rates are

based on field measurements of surface offset at several locations along the northern

Santa Rosa Range fault system and estimated ages for the faulted deposits based on calcic

soil development. We assigned the upper limit of the range of minimum rates.

14
SCHELL CREEK RANGE FAULT SYSTEM, #1241, 0.1 mm/yr (1996), 0.01 mm/yr

(2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, the slip rate subsequently assigned by dePolo (1998) was 0.010

mm/yr based on the presence of scarps on alluvium but the absence of basal fault facets.

The published value will be used herein.

SHEEP BASIN FAULT, #1115, added for 2002, 0.044 mm/yr (2002).

This fault was added in 2002 based on dePolo's (1998) reevaluation of field data

presented by Longwell (1930). Longwell (1930) reported the presence of a 34-m-high

scarp, from which dePolo (1998) determines a preferred vertical offset of 22 m. The scarp

is on a deposit assumed to be 500 ka.

SHOSHONE RANGE FAULT ZONE, #1148, 0.5 mm/yr (1996), 0.1 mm/yr (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). The slip rate subsequently assigned by dePolo (1998) was 0.335 mm/yr based

on an empirical relationship between height of basal fault facets and slip rate. For

consistency with the way other 1996 slip rates were treated, this fault is assigned a slip

rate of 0.1 mm/yr in the absence of any other data.

SIMPSON PARK MOUNTAINS FAULT ZONE, #1178, 0.3 mm/yr (1996), 0.22 mm/yr

(2002).

dePolo (1998) assigned a preferred vertical slip rate of 0.22 mm/yr based on "known"

data, and dePolo and Anderson (2000) repeated the value. However, the data that

constrain this slip rate is not documented, as are similar data for other faults used as

calibration points in his model.

SMITH VALLEY FAULT ZONE, Smith Valley fault and Sweetwater fault (1996),

#1291, 0.49 mm/yr (1996), 0.38 mm/yr (2002).

The assigned slip rate is based on work by Hayes (1985). He reported an estimated slip

rate of 0.36-0.41 mm/yr for the Smith Valley fault zone in the vicinity of Nevada Hot

Springs for the past 18 k.y.

STEENS FAULT ZONE, Pueblo Mountains fault (1996), #856, 0.1 mm/yr (1996), 0.3

mm/yr (2002).

The Pueblo Mountains fault of dePolo (1998) was merged with its appropriate extension

to the north (the Steens fault zone). The 2002 slip rate is the value that was assigned to

the Steens fault zone in 1996.

TOIYABE RANGE FAULT ZONE, #1337, 0.8 mm/yr (1996), 0.22 mm/yr (2002).

The slip rate used in 1996 was based on dePolo (1996, written commun.). The slip rate

used here is from dePolo (1998) and dePolo and Anderson (2000) and is based on

observed offset of 43.4 m and inferred age of an offset deposit of 200 ka.

WEST SPRING MOUNTAINS FAULT, #1073, added in 2002, 0.045 mm/yr (2002).

This fault was added in 2002 based on slip rates reported by Anderson and others (1995).

They indicate this fault is characterized by rates on the order of 0.02 and 0.07 mm/yr

15
(average 0.045 mm/yr). Subsequently, dePolo (1998) reported a preferred slip rate of 0.07

mm/yr, which was based on field data of Anderson and others (1995).

WESTERN GRANITE RANGE FAULT, #1610, 0.1 mm/yr (1996), 0.2 mm/yr (2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 1.503 mm/yr. Thus the assigned slip rate used here is appropriately

increased.

WESTERN TOIYABE RANGE FAULT ZONE, #1336, 0.1 mm/yr (1996), 0.2 mm/yr

(2002).

The Quaternary fault and fold database for the U.S. shows that this fault was assigned to

the 0.2-1.0 mm/yr slip-rate category, based on the magnitude of the slip rate assigned by

dePolo (1998) of 0.488 mm/yr. Thus the assigned slip rate used here is appropriately

increased.

WHITE RIVER VALLEY FAULT ZONE, #1398, 0.1 mm/yr (1996), 0.045 (2002).

This fault was included in 1996 based on preliminary data from dePolo (1996, written

commun.). However, dePolo (1998) and dePolo and Anderson (2000) calculated the

"known" slip rate of 0.02-0.07 mm/yr based on the offset of a single-event scarp at

Sawmill Canyon that is on a surface estimated to be Sangamon in age (74-200 ka) as

estimated by J. Yount. These values have little meaning and may not represent even an

approximation of the true slip rate. However, we use the average of possible maximums

here.

4.7. New Mexico 

CABALLO FAULT, #2088, 0.04 mm/yr (1996), 0.025 mm/yr (2002).

The Caballo fault was assigned a lower slip rate and a shorter length in 2002 than in

1996. Machette (1987b) and Foley and others (1988) used scarp profiles and trenches to

calculate slip rates of 0.02-0.03 mm/yr for the Caballo fault, and we used the center of

this range. New mapping shortened the recognized trace length of the fault from 79 km in

1996 to 22 km in 2002 – the northern half and southern quarter of the 1996 Caballo fault

are now recognized as separate faults with much slower slip rates.

COUNTY DUMP FAULT, part of West Mesa fault (1996), #2038, 0.03mm/yr (1996),

0.038 mm/yr (2002).

New mapping resulted in the 1996 West Mesa fault being split into a northern part, the

Zia fault, and a southern part, the County Dump fault. Mapping of an exposure by

McCalpin (1997) shows multiple faulting events resulting in 20 m of offset since 527 ka.

HUBBELL SPRINGS FAULT, #2120, added in 2002, 0.07 mm/yr (2002).

This fault was added in 2002 based on recent trenching studies that found that four

earthquakes, each producing about 1.5 m of vertical displacement, occurred at 11-13 ka,

20-30 ka, 50-60 ka, and either 90 ka or 245 ka (Personius and others, 2000). The oldest

earthquake is of highly uncertain age, but the other three bracket two complete, wellconstrained recurrence intervals. Accordingly, using the midpoints of age ranges, 3.0 m

of displacement occurred between 12 ka and 55 ka for a slip rate of 0.07 mm/yr.

16
JEMEZ-SAN YSIDRO FAULT, #2029, 0.06 mm/yr (1996), 0.020 mm/yr (2002).

The 1996 Jemez fault was assigned a greater length and a smaller slip rate for 2002 than

in 1996. The trace used in 2002 is from Machette and others (1998). They grouped the

Jemez fault with the San Ysidro fault to the south, because they are laterally continuous

and dip in the same direction. The 1996 slip rate came from Wong and others (1995),

who assigned slip rates by analogy to this and similar faults. Existing data at the time

suggested 12 m and 50 m of offset of the 1.2 Ma Bandelier Tuff along the fault. More

recent work reports offsets of 6-11 m of the 620-ka Lava Creek B ash (Izett and Wilcox,

1982; Sarna-Wojcicki and others, 1987). We used the average offsets, and averaged the

younger and older slip rates to derive 0.020 mm/yr.

LA CAÑADA DEL AMAGRE FAULT ZONE, #2005, 0.1 mm/yr (1996), 0.06 mm/yr

(2002).

The 1996 slip rate of 0.1 mm/yr is from a 10.6 Ma dike that was offset 530 m, probably

since 5 Ma (Wong and others, 1995). However, Machette and others (1998) cite 15 m of

offset of the 1.2 Ma Bandelier Tuff. This younger surface and its younger offset indicate

a slip rate of 0.012 mm/yr. We averaged the older and younger slip rates to derive 0.06

mm/yr.

LA JENCIA FAULT, #2109, 0.2 mm/yr (1996), 0.021 mm/yr (2002).

The 2002 rate was calculated from heights of two multi-event scarps on surfaces of

known ages, and from the height of a single-event scarp that ended a recurrence interval

of known duration (Machette and others, 1998).

PAJARITO FAULT, #2008, 0.09 mm/yr (1996), 0.068 mm/yr (2002).

The assigned slip rate is based on 81 m offset of the 1.2 Ma Bandelier Tuff.

SAN ANDRES MOUNTAINS FAULT, added for 2002, #2053, 0.10 mm/yr (2002).

The fault was added for 2002 based on 6- to 15-m-high scarps, which offset surfaces on

the Picacho alluvium that are 70-130 ka (Machette, 1987a). The average offset divided by

the average age yields the assigned slip rate.

SAN FELIPE FAULT ZONE, #2030a, 0.05 mm/yr (1996), 0.043 mm/yr (2002).

Personius and others (1999) calculated the minimum and maximum slip rates implied by

90-120 m scarp heights on the 2.2-2.8 Ma San Felipe basalts. We averaged these rates to

obtain 0.043 mm/yr.

ZIA FAULT, part of West Mesa fault (1996), #2046, 0.03 mm/yr (1996), 0.038 mm/yr

(2002).

New mapping resulted in the 1996 West Mesa fault being split into a northern part, the

Zia fault, and a southern part, the County Dump fault. The Zia fault was assigned a

slower slip rate in 2002 than in 1996. The assigned slip rate is based on Kelley (1977),

who reports that the 1.6 Ma Santa Fe Group is offset as much as 200 ft (61 m).

4.8. Oregon 

CAPE BLANCO ANTICLINE, #894, 2.0 mm/yr (1996), 1.4 mm/yr (2002).

Kelsey (1990) measured uplifts of marine terraces that are arched over the anticline. The

preferred ages for the terraces are 80 ka and 105 ka. Kelsey (1990) calculated a maximum

17
uplift rate of 1.4 mm/yr for the 105-ka terrace. Geomatrix Consultants, Inc. (1995)

attributed the arching and growth of the anticline to an underlying blind thrust fault.

CHEMULT GRABEN FAULT SYSTEM (EAST), East Chemult graben—Walker Rim

fault (1996), #839b, 0.4 mm/yr (1996), 0.052 mm/yr (2002).

The fault system forms the eastern side of the Chemult graben. Two slip rate estimates

are available for the graben, 0.05 mm/yr from 300 m of offset in 4.5-7 Ma volcanic rocks,

and 0.4 mm/yr from 5- to 6-m-high scarps on latest Pleistocene (15 ka) deposits

(Geomatrix Consultants, Inc., 1995). Geomatrix Consultants, Inc. (1995) notes

geomorphic expressions indicating that the eastern side of the graben probably has slower

slip rates than the western side. The Quaternary fault and fold database for Oregon

(Personius and others, in review) explains why 0.4 mm/yr probably applies only to the

western side of the graben. Thus, in 2002, 0.052 mm/yr was used for the eastern side.

COTTONWOOD MOUNTAIN FAULT, #806, 0.02 mm/yr (1996), 0.09 mm/yr (2002).

Knudsen and others (1994) used numerous fault scarp profiles and estimated ages of late

Quaternary deposits to determine long-term slip rates of 0.03-0.15 mm/yr for the

Cottonwood Mountain fault. The assigned slip rate for 2002 is the average of the

extremes.

HAPPY CAMP FAULT, Netarts Bay fault (1996), #882, 0.04 mm/yr (1996), 0.025

mm/yr (2002).

The Happy Camp fault was misidentified as the Netarts Bay fault in 1996. We follow the

established usage of the name as summarized in the Quaternary fault and fold database

for Oregon (Personius and others, in review). The Happy Camp fault was assigned a

smaller slip rate in 2002 than in 1996. The fault is known only from its 3-km-long

exposure in coastal sea cliffs. The observed offset of Quaternary sediments on the fault is

inconsistent with its being as short as 3 km. Accordingly, we followed Geomatrix

Consultants, Inc. (1995) in assigning a length of 20 km. The 1996 rate is based on 9-m

offset of Pleistocene channel deposits that are probably 200 ka to 1.6 Ma

(Geomatrix Consultants, Inc., 1995). The maximum rate from these data was used in

1996. Averaging the range of slip rates yields the assigned value.

HELVETIA FAULT, #OR2, 0.01 mm/yr (1996), 0.014 mm/yr (2002).

Geomatrix Consultants, Inc. (1995) reported 20 m of vertical separation of the upper part

of late Miocene-early Pleistocene sediments (11 Ma-750 ka). Geomatrix Consultants,

Inc. (1995) assumed, without explanation, an age of 2 Ma for the surface that is offset 20

m, and calculated the slip rate used in 1996. Averaging the resulting slip rates yields the

assigned 2002 value.

HORSE HAVEN (SIC) HILLS ANTICLINE: see Horse Heaven Hills structure (NW

trend) under Washington.

JUNIPER MOUNTAIN FAULT, #805, 0.02 mm/yr (1996), 0.01 mm/yr (2002).

The fault has Quaternary scarps but no data from which to calculate a slip rate. However,

Geomatrix Consultants, Inc. (1995) proposed a three-point distribution of possible slip

rates, and used geomorphic expression of the fault and possibly some preliminary

estimates of scarp heights to suggest a probability for each rate: 0.01 mm/yr (probability

18
0.5), 0.05 mm/yr (0.4), and 0.1 mm/yr (0.1). In 2002, the highest-probability slip rate

(0.01 mm/yr) is used here.

KLAMATH GRABEN FAULT SYSTEM (EAST), East Klamath graben fault and South

Klamath graben zone (1996), #843bc, 1.5 mm/yr (1996), 0.2 mm/yr (2002).

The 1996 East Klamath graben fault and, on strike to the south, the 1996 South Klamath

graben zone form the eastern edge of the Klamath graben. For 2002 the two faults were

combined into the Klamath graben fault system (east), following the Quaternary fault and

fold database for Oregon (Personius and others, in review). Geomatrix Consultants, Inc.

(1995) provides a three-point probability distribution of slip rate: 0.15 mm/yr (probability

0.4), 0.2 mm/yr (0.5), and 0.5 mm/yr (0.1). The age-offset data cited by Geomatrix

Consultants, Inc. (1995) and reported in the Quaternary fault and fold database for

Oregon (Personius and others, in review) are either from pre-Quaternary surfaces, which

provide very slow slip rates, or from a potentially single-rupture scarp on a mid-Holocene

ash, which provides no constraint. The highest probability rate (0.2 mm/yr) in the threepoint distribution of Geomatrix Consultants, Inc. (1995) falls between these extremes and

we used it.

PINE VALLEY GRABEN FAULT SYSTEM, BROWNLEE SECTION, Brownlee fault

(1996), #809a, 0.08 mm/yr (1996), 0.0075 mm/yr (2002).

Geomatrix Consultants, Inc. (1995) estimated three possible slip rates and assigned

probabilities to each: 0.005 mm/yr (probability of 0.4), 0.01 mm/yr (probability of 0.4),

and 0.05 mm/yr (probability of 0.2). We assigned the average of the two higher

probability rates.

PINE VALLEY GRABEN FAULT SYSTEM, HALFWAY-POSEY VALLEY

SECTION, Halfway fault and Posey Valley fault (1996), #809b, 0.03 and 0.02 mm/yr

(1996), 0.0075 mm/yr (2002).

Geomatrix Consultants, Inc. (1995) estimated three possible slip rates and assigned

probabilities to each: 0.005 mm/yr (probability of 0.4), 0.01 mm/yr (probability of 0.4),

and 0.05 mm/yr (probability of 0.2). We assigned the average of the two higher

probability rates.

RATTLESNAKE-WALLULA FAULT SYSTEM, #WA1, 0.2 mm/yr (1996), 0.043

mm/yr (2002).

This zone of northwest-striking faults is assigned a lower slip rate in 2002 than in 1996.

The zone of faults is mostly strike slip in its southeastern half and reverse in its

northwestern half. Geomatrix Consultants, Inc. (1995) estimated a 0.8 probability that the

entire system is reverse, dipping southwest, and a 0.2 probability that it is strike slip,

dipping vertically. For each alternative, they published three fault-parallel slip rates and

estimated the probability of each. For each of the six slip rates, we multiplied its

probability by the probability of the associated faulting style, to obtain the probability of

that combination of slip rate and faulting style. A fault-parallel slip rate of 0.05 mm/yr on

a reverse fault is by far the most likely, having a probability of 0.48. The other five

combinations ranged between 0.04 and 0.16. Geomatrix Consultants, Inc. (1995)

estimated that fault dips of 45 and 60 degrees are equally probable. We chose 60 degrees.

These values produce the assigned vertical slip rate of 0.043 mm/yr.

19
SANTA ROSA RANGE FAULT SYSTEM, Santa Rosa-Owyhee River-Oregon Canyon

fault zone (1996), #1508, 0.75 mm/yr (1996), 0.13 mm/yr (2002).

The assigned 2002 slip rate is based on the reported minimum rate of 0.01-0.13 mm/yr

reflecting the most recent interval of faulting (Narwold, 1999; 2000). These slip rates are

based on field measurements of surface offset at several locations along the northern

Santa Rosa Range fault system and estimated ages for the faulted deposits based on calcic

soil development. We assigned the upper limit of the range of minimum rates.

TULE SPRINGS RIMS FAULT, Eastern Alvord graben fault (1996), #858, 0.3 mm/yr

(1996), 0.1 mm/yr (2002).

The assigned slip rate is from a three-point distribution of slip rates reported by

Geomatrix Consultants, Inc. (1995). We chose the highest-probability rate for 2002.

TURNER AND MILL CREEK FAULTS, Mill Creek fault (1996), #871, 0.01 mm/yr

(1996), 0.0066 mm/yr (2002).

The assigned slip rate is based on 100 m of vertical offset (Graven, 1990; Yeats and

others, 1996) of the Miocene Columbia River Basalts (14-16.5 Ma).

WALDPORT FAULT, #886, 0.10 mm/yr (1996), 0.14 mm/yr (2002).

Scarps 15-20 m high mark the offset of an approximately 125 k.y. marine terrace across

the Waldport fault (Ticknor, 1993; Kelsey and others, 1996). The middle of the range of

scarp heights divided by the estimated terrace age gives the 2002 slip rate of 0.14 mm/yr.

WARNER VALLEY FAULTS (EAST), East Warner Valley fault North, East Warner

Valley fault South, and Northeast Long Valley fault in Nevada (1996), #827ac, 0.2

mm/yr (1996), 0.11 mm/yr (2002).

The assigned slip rate is based on the highest probability (0.4) slip rate (0.1 mm/yr)

estimated by Geomatrix Consultants, Inc. (1995).

WARNER VALLEY FAULTS (WEST), Warner Valley fault (1996), #827b, 0.2 mm/yr

(1996), 0.11 mm/yr (2002).

This fault was renamed following the Quaternary fault and fold database for Oregon

(Personius and others, in review). The fault forms the west side of the north-trending

Warner Valley graben. The Warner Valley faults (west) were assigned a smaller slip rate

in 2002 than in 1996. Slip rates are from vertical offsets of 5-8 Ma volcanic rocks that are

exposed outside the graben. There, the volcanic rocks crop out 0.6-0.8 km higher than the

elevation of the valley floor of the graben. Presumably the volcanics underlie the valley

floor as well, so 0.6-0.8 km is the minimum offset. Thus, using the average age and the

average offset, the 2002 rate is 700 m / 6.5 Ma = 0.11 mm/yr. The reference used in 1996

(Geomatrix Consultants, Inc., 1995) estimated a maximum slip rate of 0.2 mm/yr, but

assigned it a low probability of 0.01; this maximum rate was used in 1996.

WINTER RIM FAULT SYSTEM, Winter ridge-Slide Mountain fault (1996), #831, 0.6

mm/yr (1996), 0.43 mm/yr (2002).

The 1996 Winter Ridge–Slide Mountain fault was renamed the Winter Rim fault system

for 2002, following the Quaternary fault and fold database for Oregon (Personius and

others, in review). The 1996 assigned slip rate was based on the slip rates and

probabilities of 0.3 mm/yr (probability P = 0.3), 0.5 mm/yr (P = 0.5), and 0.6 mm/yr (P =

20
0.2) by Geomatrix Consultants, Inc.(1995); the maximum value was used in 1996. The 

assigned slip rate for 2002 is based on the average offset and the average age from field 

data that suggest 6.0-6.8 m of vertical offset of a 12- to 18-ka surface. 

4.9. Texas 

For most Texas faults the 1996 slip rate exceeds the assigned 2002 rate. This occurred

because the 1996 maps used slip rate values as stated by Collins and others (1996), which

was based on slip rates calculated for a critical-facility assessment (Collins and Raney,

1993). For conservatism in the critical-facility analysis, the youngest possible age for the

faulted middle Pleistocene surfaces was used (130 ka) to calculate slip rates. However,

Collins and others (1996) report that more likely age of the surfaces is 250-500 ka along

some faults and 400-500 ka along others. The conservative age assignment resulted in

comparatively high rates in 1996. In 2002, we assigned an age range of 130-500 ka to the

middle Pleistocene surfaces.

ACALA FAULT, #903, 0.14 mm/yr (1996), 0.088 mm/yr (2002).

The assigned slip rate is calculated from 18 m of offset on middle Pleistocene deposits

that are 130-500 ka (Collins and others, 1996). The 2002 assigned slip rate is based on

the average of the resulting slip rates.

AMARGOSA FAULT, #905, 0.18 mm/yr (1996), 0.11 mm/yr (2002).

The assigned slip rate is calculated from 24 m of offset on middle Pleistocene deposits

that are 130-500 ka (Collins and others, 1996). The 2002 assigned slip rate is based on

the average of the resulting slip rates.

ARROYO DIABLO FAULT, #904, 0.02 mm/yr (1996), 0.013 mm/yr (2002).

The assigned slip rate is calculated from 1.6-3 m of offset from two or more earthquakes

(Collins and Raney, 1993) on middle Pleistocene deposits that are 130-500 ka (Collins

and others, 1996). The 2002 assigned slip rate is based on the average of the resulting slip

rates.

CABALLO FAULT, #906, 0.18 mm/yr (1996), 0.11 mm/yr (2002).

The assigned slip rate is calculated from 24 m of offset on middle Pleistocene deposits

that are 130-500 ka (Collins and others, 1996). The 2002 assigned slip rate is based on

the average of the resulting slip rates.

CAMPO GRANDE FAULT, #902, 0.1 mm/yr (1996), 0.048 mm/yr (2002).

The assigned slip rate is calculated from 10 m of offset on middle Pleistocene deposits

that are 130-500 ka (Collins and others, 1996). The 2002 assigned slip rate is based on

the average of the resulting slip rates.

EAST BAYLOR MOUNTAIN–CARIZZO MOUNTAIN FAULT, East Baylor Mountain

fault (1996), #912, 0.01 mm/yr (1996), 0.0076 mm/yr (2002).

The assigned slip rate is calculated from 1.6 m of offset on middle Pleistocene deposits

that are 130-500 ka (Collins and others, 1996). The 2002 assigned slip rate is based on

the average of the resulting slip rates.

21
EAST SIERRA DIABLO FAULT, Sierra Diablo fault (1996), #910, 0.1 mm/yr (1996),

0.020 mm/yr (2002).

The 1996 Sierra Diablo fault included the 2002 East Sierra Diablo, East Flat Top

Mountain, and North Sierra Diablo faults. Data with which to calculate a slip rate is

available only from the East Sierra Diablo fault (Collins and others, 1996). The assigned

slip rate is based on 4 m of offset on middle Pleistocene deposits that are 130-500 ka

(Collins and others, 1996). The 2002 assigned slip rate is based on the average of the

resulting slip rates.

WEST DELAWARE MOUNTAINS FAULT ZONE, #911, 0.1 mm/yr (1996), 0.024

mm/yr (2002).

The assigned slip rate is based on 1.6 m of offset of an upper Quaternary surface. Offsets

are 0.9 m, 1.2 m, and 1.6 m on successively older deposits, so the 1.6 m offset could be

the result of two or more surface ruptures. An unfaulted deposit buries the fault and was

dated at 5.7 ka (uncalibrated) (Collins and Raney, 1993). Thus, the 1.6 m of offset

occurred during the past 5.7-130 ka. The 1996 slip rate, as well as the average of the

resulting slip rates (0.15 mm/yr), are inconsistent with the subdued geomorphic

expressions of the scarps. Accordingly, to obtain the 2002 assigned rate we divided 1.6 m

by the average of the age range.

WEST EAGLE MOUNTAINS–RED HILLS FAULT, #913, 0.02 mm/yr (1996), 0.013

mm/yr (2002).

The 1996 fault of this name was split into a shorter West Eagle Mountains–Red Hills

fault and the West Indio Mountains fault, following Collins and others (1996). The 2002

slip rate is based on 2.7 m of offset on middle Pleistocene deposits that are 130-500 ka

(Collins and others, 1996). The 2002 assigned slip rate is based on the average of the

resulting slip rates.

WEST INDIO MOUNTAINS FAULT, #915, 0.02 mm/yr (1996), 0.044 mm/yr (2002).

In 1996 this fault was part of the West Eagle Mountains–Red Hills fault. The two are

regarded as independent sources here following Collins and others (1996). The assigned

slip rate for the West Indio Mountains fault is calculated from 9 m offset of middle

Pleistocene deposits that are 130-500 ka (Collins and others, 1996). The 2002 assigned

rate is the average of the resulting slip rates.

WEST LOBO VALLEY FAULT ZONE, #918, 0.01 mm/yr (1996), 0.034 mm/yr (2002).

The fault zone has four sections, and the section lengths and vertical offsets appear to

increase from north to south. Along all sections, the faulted deposits are middle

Pleistocene that are 130-500 ka (Collins and others, 1996). The 1996 rate used the highest

slip rate quoted by Collins and others (1996) for either of the two middle sections of the

fault. The 2002 assigned slip rate is the average of the maximum and minimum slip rates

from the two middle sections; the maximum rate comes from the south-central section

and the minimum comes from the north-central section.

22
4.10. Utah 

HOUSE RANGE FAULT, #2430, 0.1 mm/yr (1996), excluded for 2002.

The slip rate assigned in 1996 (0.1 mm/yr) was based on the slip rate calculated by

Hecker (1993). It was based on the amount of slip during the last event and the time

since; Hecker defines it as a maximum. In actuality, such a slip rate has little meaning

and is unlikely to represent even an approximation of the true slip. Absent other data

from which to calculate a slip rate for the fault, we exclude it from consideration.

HURRICANE FAULT ZONE, #998, 0.4 mm/yr (1996); 0.1 mm/yr—northern (#998ab)

and southern (#998ef) parts, 0.2 mm/yr—central (#998cd) part (2002).

The assigned 2002 slip rates are based on recent paleoseismologic investigations (Stenner

and others, 1999; Lund and others, 2001; Amoroso and others, 2002). None of the new

late Quaternary data suggests a rate as high as that used in 1996, which was based on a

long term rate from Hamblin and others (1981). The central part of the fault appears to be

characterized by a higher slip rate than the ends based on the lateral continuity of scarps

on alluvium. The highest value of the late Quaternary single-event rates reported by Lund

and others (2001, p. 35) from Cottonwood Canyon is 0.3 mm/yr and considered to be

larger than the characteristic late Quaternary rate for the fault.

JOES VALLEY FAULT ZONE WEST FAULT, Joes Valley fault (1996), #2453, 0.2

mm/yr (1996), 0.75 mm/yr (2002).

The assigned slip rate is the average of the slip rate reported in Black and others (2000)

of 0.4-1.1 mm/yr and is based on 12 m of offset of 11- to 30-ka deposits.

MORGAN FAULT, #2353, 0.1 mm/yr (1996), 0.09 mm/yr (2002).

The assigned slip rate is the mean of the range given by Hecker (1993) of 0.03-0.15

mm/yr for the past 1-5 m.y.

SEVIER/TOROWEAP FAULT ZONE, #997, 0.36 mm/yr (1996), 0.36 mm/yr—northern

(#997a) part, 0.16 mm/yr—southern (#997bcd) part (2002).

The assigned slip rate for the southern part of the fault is the average rate obtained from

the data presented by Jackson (1990), who reports that 25-100 ka deposits are offset 6.5 

m. The slip rate for the northern part of the fault remains unchanged from 1996 and is 

from data presented by Anderson and Christenson (1989). 

STANSBURY FAULT ZONE, #2395, added for 2002, 0.4 mm/yr (2002).

The 2002 slip rate is the preferred slip rate reported by Geomatrix Consultants, Inc.

(1999).

WEST CACHE FAULT ZONE, WELLSVILLE FAULT, #2521c, added for 2002, 0.17

mm/yr (2002).

This fault was added in 2002 based on a reported late Quaternary (<25 ka) slip rate for

this part of the fault of 0.11-0.22 mm/yr (Black and others, 2000). The average of that

range is used here.

23
4.11. Washington 

DEVILS MOUNTAIN FAULT, #574, added for 2002, 0.15 mm/yr (2002).

We used the mean Pleistocene vertical slip rate from Johnson and others (2001), derived

from onshore subsurface data. The 80 ka top of the Whidbey Formation is offset

vertically by 11.9 m across the fault. We stress that this slip rate does not include possible

strike-slip motion that cannot be identified from vertical offset data.

HORSE HEAVEN HILLS STRUCTURE (NW TREND), Horse Haven (sic) Hills

anticline (1996), #578, 0.06 mm/yr (1996), 0.031 mm/yr (2002).

This feature was listed under Oregon in 1996, although the structure is entirely within

Washington. The maximum, but lower-probability slip rate from Geomatrix Consultants,

Inc. (1995) was assigned in 1996. The assigned 2002 slip rate is based on 323 m of

vertical offset of a 10.5 Ma basalt (Geomatrix Consultants, Inc., 1995; 1996).

MILL CREEK FAULT (also known as Toppenish Ridge fault), #576, added for 2002,

0.038 mm/yr (2002).

Geomatrix Consultants, Inc. (1996) cited 500 m of vertical offset of a 10.5-16.0 Ma

basalt, and calculated a fault-parallel slip rate. We used their data and calculated a

vertical slip rate of 0.038 mm/yr, from the average of the rates indicated by the range in

age of the basalt.

RATTLESNAKE-WALLULA FAULT SYSTEM, #WA1, 0.2 mm/yr (1996), 0.043

mm/yr (2002).

This zone of northwest-striking faults is assigned a lower slip rate in 2002 than in 1996.

The zone of faults is mostly strike slip in its southeastern half and reverse in its

northwestern half. Geomatrix Consultants, Inc. (1995) estimated a 0.8 probability that the

entire system is reverse, dipping southwest, and a 0.2 probability that it is strike slip,

dipping vertically. For each alternative, they published three fault-parallel slip rates and

estimated the probability of each. For each of the six slip rates, we multiplied its

probability by the probability of the associated faulting style, to obtain the probability of

that combination of slip rate and faulting style. A fault-parallel slip rate of 0.05 mm/yr on

a reverse fault is by far the most likely, having a probability of 0.48. The other five

combinations ranged between 0.04 and 0.16. Geomatrix Consultants, Inc. (1995)

estimated that fault dips of 45 and 60 degrees are equally probable. We chose 60 degrees.

These values produce the assigned vertical slip rate of 0.043 mm/yr.

SADDLE MOUNTAINS FAULT, #575, added for 2002, 0.052 mm/yr (2002).

Geomatrix Consultants, Inc. (1996) cited 405 m of vertical offset of a 10.5-14.0 Ma

basalt on the fault, and calculated a fault-parallel slip rate that would apply along the

entire length of the fault. This vertical offset developed by slip along a ramp, on which

the fault dips 60 degrees southward, and on which the fault cut through the thick, stiff

Columbia River basalts. As the 405 m of vertical uplift accumulated, it grew an anticline

atop the dipping fault ramp. However, Geomatrix Consultants, Inc. (1996) also reported

an additional 640 m of horizontal slip measured along the flat part of the fault within the

thick, soft sedimentary rocks and sediments that overlie the basalts. This 640 m of slip

also took place on the ramp, where it would have been expressed as an additional (640

m)(sin 60 deg.) = 554 m of vertical uplift if the ramp had continued to cut upward

24
through the sediments and sedimentary rocks. Instead, because the fault flattened at the

top of the ramp, this 640 m of slip merely moved the front limb of the anticline farther

north, widening the anticline instead of making it higher. Nonetheless, this 640 m

represents additional slip on the ramp since 10.5-14.0 Ma. However, Geomatrix

Consultants, Inc. (1996) was uncertain whether the 640 m of additional slip applied to the

entire length of the fault. Accordingly, they assigned a probability of 0.6 to the possibility

that the entire fault is best represented by only the 405 m of vertical uplift, and a

probability of 0.4 to the alternative that the entire fault underwent both components of

slip. We used these probabilities, offsets, and fault dip to replace the fault-parallel slip

rate of Geomatrix Consultants, Inc. (1996) with a vertical slip rate of 0.052 mm/yr.

SEATTLE FAULT ZONE: explained separately in the final documentation for the 2002

update of the national seismic hazard maps.

STRAWBERRY POINT FAULT, #571, added for 2002, 0.25 mm/yr (2002).

This slip rate is the minimum vertical uplift rate determined by Johnson and others (2001)

from onshore subsurface data. This slip rate does not include possible strike-slip motion

that cannot be identified from vertical offset data.

UTSALADY POINT FAULT, #573, added for 2002, 0.15 mm/yr (2002).

This slip rate is the minimum vertical uplift rate determined by Johnson and others (2001)

from onshore subsurface data. This slip rate does not include possible strike-slip motion

that cannot be identified from vertical offset data.

4.12. Wyoming 

BEAR RIVER FAULT, #730, added for 2002, 2.3 k.y. return time (2002).

The assigned recurrence interval is based on the timing of the most recent events on the

Bear River fault. West (1992 #826; 1993 #825; 1994 #4412) indicated faulting events at

2.4±1.1 ka and 4.6±0.7 ka.

EAST MOUNT SHERIDAN FAULTS, Factory Hill fault (1996), #766, 0.5 mm/yr

(1996), 1.4 mm/yr (2002).

New mapping led to grouping the 1996 Factory Hill fault with other active faults that

extend farther south and renaming them the East Mount Sheridan faults (Machette and

others, 2001). The assigned 2002 slip rate is based on field data that suggests 9.6 m of

vertical offset of a mid-Holocene fan.

GREYS RIVER FAULT, #728, added for 2002, 0.62 mm/yr (2002).

The assigned slip rate is derived from 9.3 m of slip in the past 15 k.y. (Jones and

McCalpin, 1992; McCalpin, 1993).

HOBACK FAULT, #772, 1 mm/yr (1996), 0.071 mm/yr (2002).

The 2002 slip rate is based on scarps as high as 10 m that formed on Bull Lakeequivalent glacial terrane (140 ka).

25
UPPER YELLOWSTONE VALLEY FAULTS, East Yellowstone River fault and West

Yellowstone River fault (1996), #761, 0.4 mm/yr (1996), 0.37 mm/yr (2002).

The East Yellowstone River fault and the West Yellowstone River fault of 1996 were

combined for 2002. The two faults strike northerly, overlap for much of their lengths, and

bound a post-glacial valley 1-2 km wide that is interpreted as a graben. If the

interpretation is valid, then the two faults are normal, dip toward each other, and intersect

at a depth of 1-2 km. Probably one is antithetic and not likely to be seismogenic.

Accordingly, we used only the longer, east-dipping fault, and assigned it a slip rate

calculated from scarps as high as 5 m on late glacial deposits (13.5 ka).

5. 2002 FAULT PARAMETERS 

Table 2. Assigned and calculated fault parameters for the 2002 maps. 

http://pubs.usgs.gov/of/2002/ofr-02-467/ofr-02-467-table2.pdf 

6. REFERENCES 

Amoroso, L., Pearthree, P.A., and Arrowsmith, J.R., 2002, Paleoseismology and 

neotectonics of the Shivwitz section of the Hurricane fault, Mohave County, 

northwestern Arizona: Arizona Geological Survey Open-File Report 02-05, 92 p., 1 

pl., scale 1:24,000. 

Anderson, L.W., and Klinger, R.E., 1996, Evaluation and characterization of Quaternary 

faulting-Bare Mountain fault, Nye County, Nevada: U.S. Bureau of Reclamation 

Seismotectonic Report 96-5, 77 p., 4 pls. 

Anderson, L.W., and O'Connell, D.R., 1993, Seismotectonic study of the northern portion 

of the lower Colorado River, Arizona, California, and Nevada: U.S. Bureau of 

Reclamation Seismotectonic Report 93-4, 122 p., 3 sheets. 

Anderson, R.E., Bucknam, R.C., Crone, A.J., Haller, K.M., Machette, M.N., Personius, 

S.F., Barnhard, T.P., Cecil, M.J., and Dart, R.L., 1995, Characterization of 

Quaternary and suspected Quaternary faults, regional studies, Nevada and California: 

U.S. Geological Survey Open-File Report 95-599, 70 p., 2 pls. 

Anderson, R.E., and Christenson, G.E., 1989, Quaternary faults, folds, and selected 

volcanic features in the Cedar City 1° x 2° quadrangle, Utah: Utah Geological and 

Mineral Survey Miscellaneous Publication 89-6, 29 p., 1 pl., scale 1:250,000. 

Baltzer, E.M., 1990, Quaternary surface displacement and segmentation of the northern 

Lemhi fault, Idaho: Binghamton, State University of New York, unpublished M.S. 

thesis, 88 p., 2 pl., scale 1:62,500. 

Bell, J.W., 1995, Quaternary map of the Mina quadrangle, Nevada: Nevada Bureau of 

Mines and Geology Field Studies Map 10, 1 sheet, scale 1:24,000. 

Bell, J.W., Caskey, S.J., and Ramelli, A.R., 2001, Paleoseismic studies in the central 

Nevada seismic belt—1954 Rainbow Mountain [abs.]: Technical report to U.S. 

Geological Survey, Reston, Virginia, under Contract 00HQGR0022, 1 p. 

Black, B.D., Hecker, S., Jarva, J.L., Hylland, M.D., and Christenson, G.E., 2000, 

Quaternary fault and fold database and map of Utah: Technical report to U.S. 

Geological Survey, Reston, Virginia, under Contract 98QGR1029, October 2000, 

unpaginated, 1pl., scale 1:500,000. 

26
Briggs, R.W., and Wesnousky S.G., 2002, Slip rate and Holocene earthquake recurrence, 

Pyramid Lake and Olinghouse fault zones, western Nevada, USA: AEG News, v. 45, 

Program with abstracts, p. 57. 

Collins, E.W., and Raney, J.A., 1993, Late Cenozoic faults of the region surrounding the 

Eagle Flat study area, northwestern trans-Pecos Texas: Technical report to Texas 

Low-Level Radioactive Waste Disposal Authority, under Contract IAC(92-93)-0910, 

74 p. 

Collins, E.W., Raney, J.A., Machette, M.N., Haller, K.M., and Dart, R.L., 1996, Map and 

data for Quaternary faults in West Texas and adjacent parts of Mexico: U.S. 

Geological Survey Open-File Report 96-002, 74 p., 1 pl., scale 1:500,000. 

Colman, S.M., 1985, Map showing tectonic features of late Cenozoic origin in Colorado: 

U.S. Geological Survey Miscellaneous Geologic Investigations I-1566, 1 sheet, scale 

1:1,000,000. 

Crone, A.J., and Wheeler, R.L., 2000, Data for Quaternary faults, liquefaction features, 

and possible tectonic features in the Central and Eastern United States, east of the 

Rocky Mountain front: U.S. Geological Survey Open-File Report 00-260, 332 p. 

dePolo, C.M., 1998, A reconnaissance technique for estimating the slip rate of normalslip faults in the Great Basin, and application to faults in Nevada, U.S.A.: Reno, 

University of Nevada, unpublished Ph.D. dissertation, 199 p. 

dePolo, C.M., and Anderson, J.G., 2000, Estimating the slip rates of normal faults in the 

Great Basin, USA: Basin Research, v. 12, p. 227-240. 

Dodge, R.L., 1982, Seismic and geomorphic history of the Black Rock fault zone, 

northwest Nevada: Golden, Colorado School of Mines T-2593, unpublished Ph. D. 

dissertation, 271 p., scale 1:24,000. 

Dohrenwend, J.C., Schell, B.A., and Moring, B.C., 1991, Reconnaissance photogeologic 

map of young faults in the Elko 1° by 2° quadrangle, Nevada and Utah: U.S. 

Geological Survey Miscellaneous Field Studies Map MF-2179, 1 sheet, scale 

1:250,000. 

Euge, K.M., Schell, B.A., and Lam, I.P., 1992, Development of seismic acceleration 

maps for Arizona: Arizona Department of Transportation Report AZ92-344, 327 p., 

5 sheets, scale 1:1,000,000. 

Foley, L.L., LaForge, R.C., and Piety, L.A., 1988, Seismotectonic study for Elephant 

Butte and Caballo Dams, Rio Grande Project, New Mexico: U.S. Bureau of 

Reclamation Seismotectonic Report 88-9, 60 p., 1 pl., scale 1:24,000. 

Frankel, A.D., Mueller, C.S., Barnhard, T.P., Perkins, D.M., Leyendecker, E.V., 

Dickman, N., Hanson, S.L., and Hopper, M.G., 1996, National seismic-hazard 

maps—Documentation June 1996: U.S. Geological Survey Open-File Report 96-

0532, 110 p. 

Geomatrix Consultants, Inc., 1995, Seismic design mapping, State of Oregon: Technical 

report to Oregon Department of Transportation, Salem, Oregon, under Contract 

11688, January 1995, unpaginated, 5 pls., scale 1:1,250,000. 

Geomatrix Consultants, Inc., 1996, Probabilistic seismic hazard analysis DOE Hanford 

site, Washington: Technical report to Westinghouse Hanford Company, Richland, 

Washington, under Contract WHC-SD-W236A-TI-002, Rev.1, February, 1996, 

366 p. 

27
Geomatrix Consultants Inc., 1999, Fault evaluation study and seismic hazard assessment, 

Private Fuel Storage Facility, Skull Valley, Utah: Technical report to Stone and 

Webster Engineering Corporation, San Francisco, California, under Contract 4790, 

118 p., scale 1:100,000. 

Graven, E.P., 1990, Structure and tectonics of the southern Willamette Valley, Oregon: 

Oregon State University, unpublished M.S. thesis, 119 p., 10 pls. 

Haller, K.M., 1988, Segmentation of the Lemhi and Beaverhead faults, east-central 

Idaho, and Red Rock fault, southwest Montana, during the late Quaternary: Boulder, 

University of Colorado, unpublished M.S. thesis, 141 p., 10 pls. 

Haller, K.M., Dart, R.L., Machette, M.N., and Stickney, M.C., 2000, Data for Quaternary 

faults in western Montana: Montana Bureau of Mines and Geology Open-File 

Report 411, 229 p. 

Hamblin, W.K., Damon, P.E., and Bull, W.B., 1981, Estimates of vertical crustal strain 

rates along the western margins of the Colorado Plateau: Geology, v. 9, p. 293-298. 

Hayes, G.F., 1985, Late Quaternary deformation and seismic risk in the southern Sierra 

Nevada Great Basin boundary zone near the Sweetwater Mountains, California and 

Nevada: Reno, University of Nevada, unpublished M.S. thesis, 135 p. 

Hecker, S., 1993, Quaternary tectonics of Utah with emphasis on earthquake-hazard 

characterization: Utah Geological Survey Bulletin 127, 157 p., 6 pls., scale 

1:500,000. 

Hemphill-Haley, M.A., Knuepfer, P.L.K., Forman, S.L., and Smith, R.P., 1992, 

Paleoseismic investigations of the southern Lemhi fault, Idaho: Technical report to 

U.S. Department of Energy, under Contract DE-AC07-761D01570, March 1992, 

32 p. 

Izett, G.A., and Wilcox, R.E., 1982, Map showing localities and inferred distributions of 

the Huckleberry Ridge, Mesa Falls, and Lava Creek ash beds (Pearlette family ash 

beds) of Pleistocene age in the Western United States and southern Canada: U.S. 

Geological Survey Miscellaneous Investigations Map I-1325, 1 sheet, scale 

1:4,000,000. 

Jackson, G.W., 1990, Tectonic geomorphology of the Toroweap fault western Grand 

Canyon, Arizona—Implications for transgression of faulting on the Colorado 

Plateau: Arizona Geological Survey Open-File Report 90-4, 67 p., 2 pls., scale 

1:24,000. 

Johnson, S.Y., Dadisman, S.V., Mosher, D.C., Blakely, R.J., and Childs, J.R., 2001, 

Active tectonics of the Devils Mountain fault and related structures, northern Puget 

Lowland and eastern Strait of Juan de Fuca region, Pacific Northwest: U.S. 

Geological Survey Professional Paper 1643, 46 p., 2 pls. 

Jones, L.C.A., and McCalpin, J.P., 1992, Quaternary faulting on the Grey's River fault, a 

listric normal fault in the overthrust belt of Wyoming: Geological Society of 

America Abstracts with Programs, v. 24, no. 6, p. 20. 

Kelley, V.C., 1977, Geology of Albuquerque basin, New Mexico: New Mexico Bureau 

of Mines and Mineral Resources Memoir 33, 60 p., 2 pls. 

Kelsey, H.M., 1990, Late Quaternary deformation of marine terraces on the Cascadia 

subduction zone near Cape Blanco, Oregon: Tectonics, v. 9, no. 5, p. 983-1014. 

28
Kelsey, H.M., Ticknor, R.L., Bockheim, J.G., and Mitchell, C.E., 1996, Quaternary upper 

plate deformation in coastal Oregon: Geological Society of America Bulletin, v. 

108, no. 7, p. 843-860. 

Knudsen, K.L., Wong, I.G., Bott, J.D.J., Weber, G.E., Silva, W.J., and Lettis, W.R., 

1994, Seismotectonic evaluation, Agency Valley and Bully Creek Dams, Vale 

Project, east-central Oregon: Draft report prepared for U.S. Department of the 

Interior, Bureau of Reclamation, 171 p., 4 pls. 

Kreps, J., Fritz, W.J., Sears, J.W., and Wampler, J.M., 1992, The 6 Ma Timber Hill basalt 

flow—Implications for late-Cenozoic drainage systems and the onset of Basin-andRange style faulting, southwestern Montana: Geological Society of America 

Abstracts with Programs, v. 24, no. 6, p. 22. 

Longwell, C.R., 1930, Faulted fans west of the Sheep Range, southern Nevada: 

American Journal of Science, v. 20, no. 115, p. 1-13. 

Lund, W.R., Pearthree, P.A., Amoroso, L., Hozik, M.J., and Hatfield, S.C., 2001, 

Paleoseismic investigation of earthquake hazard and long-term movement history of 

the Hurricane fault, southwestern Utah and northwestern Arizona—Final technical 

report: Technical report to U.S. Geological Survey, Reston, Virginia, under Contract 

99HQGR0026, July 31, 2001, 71 p. 

Lundstrom, S.C., 1986, Soil stratigraphy and scarp morphology studies applied to the 

Quaternary geology of the southern Madison Valley, Montana: Arcata, California, 

Humboldt State University, unpublished M.S. thesis, 53 p., 1 pl., scale 1:24,000. 

Machette, M.N., 1987a, Preliminary assessment of paleoseismicity at White Sands 

Missile Range, southern New Mexico—Evidence for recency of faulting, fault 

segmentation, and repeat intervals for major earthquakes in the region: U.S. 

Geological Survey Open-File Report 87-444, 46 p. 

Machette, M.N., 1987b, Preliminary assessment of Quaternary faulting near Truth or 

Consequences, New Mexico: U.S. Geological Survey Open-File Report 87-652, 40 

p. 

Machette, M.N., Personius, S.F., Kelson, K.I., Haller, K.M., and Dart, R.L., 1998, Map 

and data for Quaternary faults and folds in New Mexico: U.S. Geological Survey 

Open-File Report 98-521, 443 p., 1 pl., scale 1:750,000. 

Machette, M.N., Pierce, K.L., McCalpin, J.P., Haller, K.M., and Dart, R.L., 2001, Map 

and data for Quaternary faults and folds in Wyoming: U.S. Geological Survey 

Open-File Report 01-461, 154 p., 1 pl., scale 1:750,000. 

Mathieson, E.L., 1983, Late Quaternary activity of the Madison Range fault along its 

1959 rupture trace, Madison County, Montana: Stanford, California, Stanford 

University, unpublished M.S. thesis, 169 p., 4 pls. 

McCalpin, J.P., 1993, Neotectonics of the northeastern Basin and Range margin, western 

USA: Zeitschrift fuer Geomorphologie N. Folge, v. 94, p. 137-157. 

McCalpin, J.P., 1997, Paleoseismicity of Quaternary faults near Albuquerque, New 

Mexico: Technical report to U.S. Geological Survey, under Contract 1434-HQ-96-

GR-02751, 18 p. 

Narwold, C.F., 1999, Late Quaternary faulting along the Quinn River fault zone—A soils 

investigation, in Quaternary geology of the northern Quinn River and Alvord 

Valleys, southeastern Oregon: Friends of the Pleistocene Field Trip Guide, 

September 24-26, 1999, Appendix 1, p. 1-18. 

29
Narwold, C.F., 2000, Late Quaternary faulting along the Quinn River fault zone, northern 

Nevada-southeastern Oregon: Arcata, California, Humboldt State University, 

unpublished M.S. thesis, 68 p. 

Nitchman, S.P., 1991, Peterson Mountain fault: Nevada Bureau of Mines and Geology 

Preliminary Fault Evaluation Report, 3 p., scale 1:62,500. 

Olig, S.S., Gorton, A.E., Bott, J.D., Wong, I.G., Knuepfer, P.L.K., Forman, S.L., Smith, 

R.P., and Simpson, D., 1995, Paleoseismic investigation of the southern Lost River 

fault zone, Idaho: Technical report to Lockheed Idaho Technologies Company, 

Idaho National Engineering Laboratory, Idaho Falls, Idaho, under Contract C93-

134020, June 1995, 81 p., 5 pls. 

Ostenaa, D., Manley, W., Gilbert, J., LaForge, R., Wood, C., and Weisenberg, C.W., 

1990, Flathead Reservation regional seismotectonic study—An evaluation for dam 

safety: U.S. Bureau of Reclamation Seismotectonic Report 90-8, 161 p., 7 pls. 

Ostenaa, D.A., Losh, S.L., and Nelson, A.R., 1981, Evidence for recurrent late 

Quaternary faulting, Sawatch fault, upper Arkansas Valley, Colorado, in Junge, 

W.R., ed., Colorado tectonics, seismicity and earthquake hazards—Proceedings and 

field trip guide: Colorado Geological Survey Special Publication 19, p. 27-29. 

Pearthree, P.A., 1998, Quaternary fault data and map for Arizona: Arizona Geological 

Survey Open-File Report 98-24, 122 p., 1 sheet, scale 1:750,000. 

Personius, S.F., Eppes, M.C., Mahan, S.A., Love, D.W., Mitchell, D.K., and Murphy, A., 

2000, Log and data from a trench across the Hubbell Spring fault zone, Bernalillo 

County, New Mexico: U.S. Geological Survey Miscellaneous Field Studies Map 

MF-2348, 1 sheet. 

Personius, S.F., Machette, M.N., and Kelson, K.I., 1999, Quaternary faults in the 

Albuquerque area—An update, in Pazzaglia, F.J., and Lucas, S.G., eds., 

Albuquerque geology: New Mexico Geological Society Guidebook, 50th Annual 

Field Conference, September 22-25, 1999, p. 189-200. 

Pierce, K.L., and Morgan, L.A., 1992, The track of the Yellowstone hot 

spot—Volcanism, faulting, and uplift, in Link, P.K., Kuntz, M.A., and Platt, L.B., 

eds., Regional geology of eastern Idaho and western Wyoming: Geological Society 

of America Memoir 179, p. 1-53, 1 pl. 

Ramelli, A.R., and dePolo, C.M., 1997, Trenching and related studies of the northern 

Sierra Nevada Range-front fault system: Technical report to U.S. Geological Survey, 

Reston, Virginia, under Contract 1434-95-G-2606, 21 p., scale 1:62,500. 

Ramelli, A.R., dePolo, C.M., and Bell, J.W., 1994, Synthesis of data and exploratory 

trenching along the northern Sierra Nevada fault zone: National Earthquake Hazards 

Reduction Program, Final Technical Report, 65 p., scale 1:100,000. 

Reheis, M.C., 1991, Geologic map of late Cenozoic deposits and faults in the western 

part of the Rhyolite Ridge 15' quadrangle, Esmeralda County, Nevada: U.S. 

Geological Survey Miscellaneous Investigations Map I-2183, 1 sheet, scale 1:24,000. 

Ruleman, C. A., III, 2002, Quaternary tectonic activity within the northern arm of the 

Yellowstone tectonic parabola and associated seismic hazards, southwest Montana: 

Bozeman, Montana State University, unpublished M.S. thesis, 158 p. 

Sarna-Wojcicki, A.M., Morrison, S.D., Meyer, C.E., and Hillhouse, J.W., 1987, 

Correlation of upper Cenozoic tephra layers between sediments of the Western 

United States and eastern Pacific Ocean and comparison with biostratigraphic and 

30
magnetostratigraphic age data: Geological Society of America Bulletin, v. 98, p. 

207-223. 

Scott, W.E., Pierce, K.L., and Hait, M.H., Jr., 1985, Quaternary tectonic setting of the 

1983 Borah Peak earthquake, central Idaho: Bulletin of the Seismological Society of 

America, v. 75, p. 1053-1066. 

Sonderegger, J.L., Schofield, J.D., Berg, R.B., and Mannick, M.L., 1982, The upper 

Centennial Valley, Beaverhead and Madison Counties, Montana: Montana Bureau 

of Mines and Geology Memoir 50, 53 p., 4 pls. 

Stenner, H.D., Lund, W.R., Pearthree, P.A., and Everitt, B.L., 1999, Paleoseismic 

investigation of the Hurricane fault in northwestern Arizona and southwestern Utah: 

Arizona Geological Survey Open-File Report 99-8, 137 p. 

Stickney, M.C., and Bartholomew, M.J., 1987, Seismicity and late Quaternary faulting of 

the northern Basin and Range province, Montana and Idaho: Bulletin of the 

Seismological Society of America, v. 77, p. 1602-1625. 

Ticknor, R., 1993, Late Quaternary crustal deformation on the central Oregon coast as 

deduced from uplifted wave-cut platforms: Western Washington University, 

unpublished M.S. thesis, 70 p. 

Vincent, K.R., 1995, Implications for models of fault behavior from earthquake surfacedisplacement along adjacent segments of the Lost River fault, Idaho: Tucson, 

University of Arizona, unpublished Ph.D. dissertation, 152 p. 

Weick, R.J., 1990, Structural, tectonic and Quaternary study of the eastern Madeline 

Plains, California and southwestern Smoke Creek Desert, Nevada: Reno, University 

of Nevada, unpublished M.S. thesis, 160 p. 

Wells, D.L., and Coppersmith, K.J., 1994, New empirical relationships among 

magnitude, rupture length, rupture width, rupture area, and surface displacement: 

Bulletin of the Seismological Society of America, v. 84, p. 974-1002. 

Wenrich, K.J., Billingsley, G.H., and Blackerby, B.A., 1995, Spatial migration and 

compositional changes of Miocene-Quaternary magmatism in the western Grand 

Canyon: Journal of Geophysical Research, v. 100, no. B7, p. 10,417-10,440. 

West, M.W., 1992, An integrated model for seismogenesis in the Intermountain seismic 

belt: Bulletin of the Seismological Society of America, v. 82, p. 1350-1372. 

West, M.W., 1993, Extensional reactivation of thrust faults accompanied by coseismic 

surface rupture, southwestern Wyoming and north-central Utah: Geological Society 

of America Bulletin, v. 105, p. 1137-1150. 

West, M.W., 1994, Seismotectonics of north-central Utah and southwestern Wyoming: 

Utah Geological Survey Special Study 82 (Paleoseismology of Utah, volume 4), 93 

p., 5 pls. 

Widmann, B.L., Kirkham, R.M., and Rogers, W.P., 1998, Preliminary Quaternary fault 

and fold map and database of Colorado: Colorado Geological Survey Open-File 

Report 98-8, 331 p., 1 pl., scale 1:500,000. 

Willoughby, C.H., 1997, Character, timing, and rate of late Quaternary faulting on the 

northwestern side of the Ruby Mountains and East Humboldt Range, northeastern 

Nevada: Reno, University of Nevada, unpublished M.S. thesis, 52 p. 

Witkind, I.J., 1975, Geology of a strip along the Centennial fault, southwestern Montana 

and adjacent Idaho: U.S. Geological Survey Miscellaneous Investigations Map I890, 1 sheet, scale 1:62,500. 

31
Wong, I., Kelson, K., Olig, S., Kolbe, T., Hemphill-Haley, M., Bott, J., Green, R., 

Kanakari, H., Sawyer, J., Silva, W., Stark, C., Haraden, C., Fenton, C., Unruh, J., 

Gardner, J., Reneau, S., and House, L., 1995, Seismic hazards evaluation of the Los 

Alamos National Laboratory: Technical report to Los Alamos National Laboratory, 

Las Alamos, New Mexico, February 24, 1995, 3 volumes, 12 pls., 16 appen. 

Woodward-McNeil & Associates, 1974, Geotechnical investigation, Yuma Dual-Purpose 

Nuclear Plant, Yuma, Arizona, Appendices E and F: Unpublished Report to the Salt 

River Project, Phoenix, Arizona. 

Yeats, R.S., Graven, E.P., Werner, K.S., Goldfinger, C., and Popowski, T.A., 1996, 

Tectonics of the Willamette Valley, Oregon, in Rogers, A.M., Walsh, T.J., 

Kockelman, W.J., and Priest, G.R., eds., Assessing earthquake hazards and reducing 

risk in the Pacific Northwest: U.S. Geological Survey Professional Paper 1560, v. 1, 

p. 183-222. 

32