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)013ALZW/84/11/1/0

MEMORANDUM FOR:

FROM:

tr'Reor p IV WM Proudct L. ....- DCcfet No.

PDR A0'NOV 26 14iWDR '--

Distributiorn __ _

(Retum to WM,623SS)Malcolm R. Knapp, ChiefGeotechnical BranchDivision of Waste Management, NMSS

Krisfin B. Westbrook, Project ManagerGeology-Geophysics SectionGeotechnical BranchDivision of Waste Management, NMSS

Dis ibution:

NMSS rfRBrowningMBellJBuntingPJustusJCutlerKWestbrook & rfRWright, WMRPPDRLPDR

SUBJECT: TRIP REPORT: NRC GEOLOGY MAPPING FIELD REVIEW FORTHE BASALT WASTE ISOLATION PROJECT REGION

On October 22 through October 26, 1984, Philip Justus, Kristin Westbrook, andJonathan Cutler of the Division of Waste Manangement, Geotechnical Branch(WMGT), went on five one-day trips from Richland, Washington for a geologicalmapping review. The trip was sponsored by the Department of Energy's BasaltWaste Isolation Project Office.

Attached to this memo is a copy of the list of attendees (enclosure one - onepage) and data review sheets with maps locating the areas visited (enclosuretwo- eighty two pages).

45/Kristin B. Westbrook, Project ManagerGeology-Geophysics SectionGeotechnical BranchDivision of Waste Management, NMSS

Enclosures:As stated

"3 a e*4 T I :4~ ~L +t4~j - 4~ r.~(. t D <H6 t f i 5 ; + ( L oc,7

8501110309 841126PDR WASTEWm-10 PDR

4AME :Kwestbrook:dW *

)ATE :84/11/26 4 L1L .kG jfI,

SOCLOSuRE WNtAER I1 /pO/-DOE/NRC GEOLOGY DATA REVIEW MEETING

OCTOBER 22-26, 1984

BOB COOKBOB WRIGHTMIKE THOMPSONBILL BREWERJIM MECCASUE PRICETERRY TOLANJAY SMITHKRISTIN WESTBROOKBOB WHITNEYPHIL JUSTUSKARL FECHTDON WESTB. GEOFFREY JONESJONATHAN CUTLERBOB JACKSONBILL KIELBRUCE HURLEYJIM BAZEMOREMAURICE D. VEATCHLINDA LEHMANSTEVE REIDELFRANK SCHMITTDICK BERRYDICK GALSTERART LASSILAJOHN KOVACKSDAVE DAHLEM

NRCNRCDOE-RLWA ST DEPT OF ECOLOGYDOE-RLROCKWELLROCKWELLCONSULTANTNRCLLNL (UNR-RENO)NRCROCKWELLGOLDER ASSOC.GEOTRANS INC.NRCWESTON (DOE-HQ)WPPSSDOE-RLLICENSINGROCKWELLCONSULTANTROCKWELLNRCNRC CONSULTANTNRC CONSULTANT (CORPS OF ENGR.)DOE-RLDOE-RLDOE-RL

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ENCLOSURE NUMBER

NRCBWIP FIELD TRIP AREAS--1o/22/84 tolO/26/84

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GEOLOGY FIELD REVIEW CHECKLIST

1. Outcrop/stop identification.

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2. Outcrop/stop description.

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GEOLOGY MAP DATA REVIEW CHECKLIST

1. What d rea does the map cover?

R;k4e.2. What type of map is it?

Geo lc. s kecjWhat is the scale?

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3. Who did the field work?

oe, Rt Qidel - RocJcwej/4. What is (are) prominent feature(s) shown to date?

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5. Why was this mapping project undertaken and when was the mapbegun/completed?

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6. What methods, procedures, or techniques were used to map this area?

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7. When is the map toalready published,

be published? In what publication series?when and in what document?

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Preliminary Geologic Sketch Map of a Portion of theNorth End of Yakima Ridge

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S. P. Reidel1986

Section Line.

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Rattlesnake Ridge interbed

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Scale0 500 000ft.

Reviewer . /" I/f__ aDate 7iQ i F


1. What area does the map cover?

Vet n-M e Iq 1o-5 ti're"- 1NOAr 2c [QCIJ04 n v,.\A1 0s r -YAe C.OI4ylA , Rve K2. What type of map is it? What is the scale?

Gleo 110ji C' V\ P oVt +tP rqphA;h L[S I 1'~0003. Who did the field work?

TtrtTo 6e - Rockwe4f34. What is (are) prominent feature(s) shown to date?E-J Tr'evdkn Crt Creoe Sjnc/iin,

Whis6P-Lj vtcl Frsj Fl - Cfqwrog) E-\d\/Hells NtchThn sF- i-ox, E-vW* V I5. Why was this mapping proJect undertaken and when wa

begun/completed?

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2. Outcrop/sto "fscription. ,/VeXt o' kie Vc.& Arq cowh(pA o( Scddoq Potz I100 of XJe4-'c v)9pO54,' n 9 (0K, / o Rs lowcb S +I^ c t 3o F/oL. JfH nc I 11ow o t},.t e

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1. Outcro /stop identification.

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1. Outcrop/stop identification. SloP _ I

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EXPLANATION

o Fault: dashed where inferred, dotted whereconcealed. Sall on downthrown side.

Anticline: arrows indicate direction of dip- m and plunge; dashed where inf erred, dottedwhere concealed.

Syncline: arrows indicate direction of dipp÷ b and plunge. dashed where mnferred, dotted

where concealed.

~ject No. Hanford FSARLOAINMPFgr494wrd 4 0 LOCATION MAP |_Figure_|Woodward-Clye ConwlftantsI

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WALLULA FAULT ZONE

Description:

Strike:

Dip:

Sense ofMotion:

Amount ofDisplacement:

The Wallula fault zone is a part of the Rattlesnake -Wallula alignment (RAW). RAW extends for about 120 kmfrom near Rattlesnake Mountain to the Hite fault. RAWis defined by the alignment of northwest-trending anti-clines, doubly-plunging anticlines, monoclines and faults.The Wallula fault zone extends from near Wallula Gap south-east to the Hite fault. It exhibits consistent down-to-the-northeast net displacement.

Northwest

550 SW to high angle

Reverse oblique (?); dextral strike-slip and reverse havealso been proposed.

a

0

0

Yellepit _- 45 - 60 m (vertically)Wallula Junction - 120 m (vertically; maximum)Warm Springs - 150 m (vertically; maximum)

Timing ofDisplacement:

* Finley Quarry - older than 70,000 yrs (U-Th) possiblyolder than 200,000 - 250,000 yrs.

* Yellepit - Kennewick fanglomerate undisplaced (20,000yrs; U-Th).

0

0

Bingham's Lineament - non-tectonic feature.

Warm Springs - Touchet sediments (13,000 yrs) undisplaced;Pleistocene colluvium (>100,000 yrs) are displaced.

* Umapine - Displaced Touchet sediments (13,000 yrs) nearthe Wallula fault, however, the structural relationshipof these faults to the Wallula fault has not been estab-lished but implied.

* Buroker fault - Reworked Touchet sediments (13,000 yrs),Palouse soil (32,000 - 75,000 yrs) and Pleistocene gravelsare displaced by a reverse fault whose structural relation-ship with the Wallula fault zone is unclear.

Capability:

References:

The Wallula fault is classified as being capable.

1) Woodward-Clyde Consultants, 1982, Wallula Gap Fault ZoneTrenching and Mapping, prepared for Washington PublicPower Supply System, August, 1982.

\ epsJ s r%40t-c

16

SI- 0of I 1 0 />-/

Wallula Fault ZonePage Two

References: 2) U.S. NRC, 1982, SER, WPPSS Nuclear Project No. 2, Supple-(contd.) ment No. 1, Docket No. 50-397, August, 1982.

3) Kienle, C.F. and others, 1980, Geologic Reconnaissance ofParts of the Walla Walla and Pullman, Washington andPendleton, Oregon 10 x 20 AHS Quadrangles, report preparedfor the U.S. Army Corps of Engineers by Foundation Sciences,Inc., Portland, Oregon.

4) Kienle, C.F. and others, 1979, Geologic Reconnaissance ofthe Wallula Gap, Washington - Blue Mountains - LaGrande,Oregon Region, report prepared for Washington Public PowerSupply System by Shannon and Wilson, Inc., Portland, Oregon.

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TOUCHET SEDIMENTS

The Touchet sediments are slackwater deposits of the late PleistoceneMissoula floods that swept the Columbia Plateau. They occur to eleva-tion of about 350 m and consist of a lower rhythmically bedded seriesof turbidites and upper massively bedded silts. Clastic dikes areubiquitous in the Touchet sediments and were formed by a number ofmechanisms including hydraulic injection, liquefaction and infilling.The latest Touchet sediments are about 13,000 yrs old based on thepresence of Cascade volcanoes tephra in the upper section.

Reference: Woodward-Clyde Consultants, 1981, Task D3, QuaternarySediments Study of the Pasco Basin and Adjacent Areas,prepared for Washington Public Power Supply System,July, 1981.

Woodward.Clyde Consultants 19b i

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one-third of the volume of the larger lake. BaKer (1973)

states that the second f illing of glacial Lake Missoula may

have been associated with the advance of the ice sheet at Lake

Pend Oreille. Bjornstad (1980) and this study note that two

sequences of fine-grained deposits at the Cummings Bridge

locality separated by a major erosional unconformity are evi-

dence for two separate floods.

3.5.2.2 The Touchet Beds. The central, low parts of smaller

basins, such as Walla Walla and Yakima, contain the best pre-

served slackwater deposits, which exhibit the most complete

suite of sedimentary features and structures. At. elevations

mucn aoove 180 m, the rhythmically bedded slackwater deposits

give way to more massive deposits. Slackwater deposits have

Deen reported up to elevation 350 m. The silty facies of

flood deposits have ceen described by many workers since they

were first recognized by Bretz (1929) as oeing flood relat-l

ed. Flint (1938), in his denouncement of Bretz' flood hypo-

thesis, coined the phrase Touchet beds to describe the series

of rnythmically deposited sands and silts that occur in the

Walla Walla Valley. Similar deposits have been recognized in

the YaKima Valley and Umatilla Basin. Allison (1933) also

identified similar rhythmically deposited sands and silts in

the Willamette Valley in Oregon, a side valley of the Columbia

River downstream of the Pasco Basin.

The principal characteristic of the Touchet beds at their type

locality is that the sands and silts were deposited in a

series of turbidites (Baker, 1973) or rhythmites (Carson and

others, 1978). Baker (1973) describes a series of measured

stratigraphic sections along the Tucannon River (see Figure

D3-1 for location), a tributary of the Snake River. These

sections, which show a gradual fining upvalley, are composed

of a sequence of rhythmically bedded sand and silt. Each

rhythmite typically consists of the following sequence:

=- - -- 'I I5- ~ ~ ? , Kioitt.!

Woodward-Clyde Consttants

1. A basal layer of structureless course sand and| granules.

.2. Horizontally stratified medium and fine sand.

| 3. Current-ripple bedding in fine sands and coarse

silts.

4. Parallel lamination in medium and fine silts.

This sequence corresponds to most of Bouma's (1962) turbidite

I sequence, which contains five elements (a to e) in a complete

unit. Baker (1973) regards the sequence to be precisely what| Kuenen (1967) considers to be diagnostic for a turbidite.

| Bretz cited the up-valley foreset bedding as evidence for his

flood theory for the formation of the scablands and the depos-I ition of the Touchet beds, because this cannot be explained by

normal streamn deposition. The Burlingame Ditch locality af-

fords some fine examples of up-valley foreset bedding and

rnythmites. Figure D3-12 shows part of a rhythmite exposed in

the west wall of Burlingame Ditch. The basal layer of medium-

| brown sand is overlain (at the base of the knife handle) byforeset-oedded coarse sand. This 30-cm-thick unit has a plane

J top, defined by a very sharp contact with fine sand. Theforeset bedding indicates an apparent paleoflow direction of

southwest to northeast, i.e., up-valley. The lower foreset-bedded unit is separated from an upper 10-cm-thick foreset-

bedded unit by a laminar-bedded medium- to coarse-sand unit,

whose bedding parallels ooth the lower and upper surfaces from

the unit. The upper unit shows very pronounced foreset

| bedding that indicates an apparent paleoflow direction of

southwest to northeast, coincident with the lower unit. This

| upper unit is overlain by a brown medium sand that has weaklyexposed sinusoidal ripple bedding.

I

lIil

Woodward-Clyde Consutat

Figure D3-13 shows a close-up view of a complete rhythmite. aThe hammer head is on a ledge formed by medium-grained sand at

the top of the subadjacent rhythmite. The basal 22 cm of the

rhythmite is formed by dark-colored, basaltic, medium to

coarse sand and has laminar bedding (equivalent to Bouma's

119621 unit lb"). This bedding is nearly horizontal. Tnelower one-third of the thick medium-sand unit contains sinus-

oidal ripple oedding that corresponds to Bouma's (1962) unit

Ic" in this turbidite sequence. The upper two-thirds of the

thick medium-sand unit shows progressively less ripple bedding

and progressively, more laminar bedding, corresponding to

Bouma's unit Id".

The round structure just left of the hammer in Figure D3-13

and the similar structures in Figure D3-14 are composed of

very weakly cemented silt, fine sand, and some medium sand..

These structures are inferred to have been pebbles of frozen

sediments. These frozen clasts probably came from a frozen

surface that was ripped up by the floodwaters. Due to the

high concentration of sand grains, the frozen pebbles could

not float and were carried as bed load with the coarser sand

forming the rhythmite. Figure D3-14 shows that the Majority

of such structures occur within or very close to tne coarser

facies of the rhythmite.

The base of the superadjacent rhythmite, defined by the dark-

colored basaltic coarse sand, is essentially parallel to the

laminations in the upper Id' unit of the main rhythmite

shown. There is no angular unconformity between rhythmites in

this case, although there is some local channeling of the

basal unit (Nbw) into the top of the subadjacent unit Id" of

the underlying rhythmite. Presumably, subaerial exposure of

the upper part of any rhythmite for a period of decades as

suggested by Waitt, 1980, would have left marked channels in

the top of the rhythmites and probably have incised complete

-E I P ) I / eWoodward-Clyde ConsultantsVJPPSS AeKmovf

rhythmites. This is generally not the case at this locality.

Ejornstad (1980), in a study of various localities within the

Walla Walla Valley (e.g., Gardena Cliff, Burlingame Ditch,

Cumming's Bridge), compares the assemblage of structures to

Bouma's (1962) turbidite deposits. Bjornstad (1980) notes

that the sections he measured typically contain Bouma's se-

quence of units Nb', Ic", and Id", and basal unit 'la". The

upper pelitic unit wed is absent. Bouma (1962) ascribes the

absence of basal units in the sequence to distance from the

source; the absence of upper units could be due to erosion by

succeeding turbidites.

Bjornstad (1980) argues that the sections ooserved in the

Walla Walla Valley and Bouma's (1962) definition of a turoi-

dite sequence are comparable. He further argues that the

general lack of major erosional features between adjacent

rnythmites and the lack of regularly distriouted basal grav-

els, which would be expected to occur between separate floods,

indicate that the entire sequence of rhythmites must have been

deposited as pulses into a lake produced by a single flood.

Bjornstad (1980) has identified 58 rhythmites at the Gardena

Cliff exposure and 46 at Burlingame Ditch. A major erosional

unconformity that separates two sequences of rhythmites,

exposed at the Cummings Bridge locality, indicates there were

two separate floods.

Waitt (1980) also compares the rhythmites at Burlingame Ditch

with Bouma's (1962) turbidite deposits and considers them ana-

logous. He notes that the basal sand of many rhythmites con-

tain foreset beds that dip up-valley. Waitt notes that at the

type locality near Touchet, the coarse base of each rhythmite

is conspicuously channeled into the preceding rhythmite.

Waitt (1980) proposes that each rhythmite represents a single

flood on the basis of: 1) erosion between adjacent

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rhythmites; 2) the presence of rodent burrows throughout the

Burlingame Ditch exposure, which were not observed during this

study; 3) the widespread remains of vertebrate fossils; 4) the

preservation of unbroken delicate shells, such as charophytes

(Charm Sp.), that normally live in water depths of less than

10 m; and 5) the cleanliness of tephra units within the

Touchet beds. He suggests that each rhythmite records an up-

valley surge of rapidly deepending water crossing dry land,

then retreating again. Waitt (1980) proposes that at least 40

floods (jokulhlaups) have occurred in southern Washington in

late Pleistocene time.

There are several factors that can be used to argue either for (

or against the many-floods hypothesis of Waitt (1980). He

notes that the ice sheet that could have produced the ice dam

retaining glacial Lake Missoula has been bracketed byC14 dates of 19.1 + 2.4 and 11 +- 1.8 ka BP. If the Pend

Oreille ice lobe dammed Lake Missoula for perhaps 7000 years,

then the mean interval between the 40 floods would be about

175 years. The present rate of flow in the Clark Fork Riveris about 7460 ft3/s; this would fill the 500-mi3 lake in some

320 years. If the rate of flow or the volume of the lake werevaried by a factor of 2, then the lake could completely fill

in 160 years or half fill in 80 years. This revised rate

would adequately accommodate Waitt's 40 floods.

Bjornstad (1980), however, notes that up to 62 rhythmitesexist. This implies that Waitt's model would have to accom-

modate 62 floods, which would reduce the average interval

between floods to less than 115 years.

The presence of undamaged delicate shells and of clean tephraunits that occur inter-rhythmite instead of intra-rhythmite,

is difficult to explain unless many floods are postulated.

mThI / /vfs/b'+Woodward.Clyde Consultants

WJPPSS' 4cndoV

A major drawback to the many-floods hypothesis concerns

erosion of the Touchet beds and the deposition of loess.

After the first of the postulated 40 floods, the land would be

stripped bare and backflooded areas, such as the Walla Walla

Valley, would look something like a mud flat after the tide

has gone out. Winds, which are common on the meltwater side

of an ice sheet, would have blown the recently deposited fine

sand and silt into dunes. Gully erosion would rapidly remodel

the dune surfaces.

The second of the u40 floods" 80 to 320 years later would,

therefore, nave oeen deposited on a significant erosion

surface. This sequence would have repeated itself 40 times

(according to Waitt, 1980) and a section, such as Burlingame

Ditch or Gardena Cliffs, would surely show considerable

evidence of the channeling and dune formation. But, in the

Burlingame Ditch exposure, the depth of any channeling rarely

exceeds the thickness of a single rhythmite, which ranges from

aooat 1.5 m near the base to about 0.5 m near the top of the

section.

The exposure that does most to refute the 40-flood hypothesis

is known as Cummings Bridge (Bretz, 1929; Bjornstad, 1980).

It is located on the Walla Walla River south of Reese in SE

1/4, Section 35, T7N R32E, and in NE 1/4, Section 2, T6N

R32E. The base of tne cliff lies on what may be pre-Palouse

loess. This ioess is overlain by approximately 8 m of flood

gravels, which in turn are overlain by at least 20 brownish

rhythmites of the Touchet beds. These rhythmites are collec-

tively about 15-18 m thick. Lapping onto these brownish

rhythmites, both to the south and to the north, and separated

by a major erosional unconformity, there is a sequence of

younger greyish rhythmites. The older rhythmites are ap-

parently flat lying, while the younger greyish rhythmites have

a pronounced dip to the northwest. This exposure clearly

Be- s~~~~~~'Tof l 'ob/s-,/s-Woodward.Clyde Consultants

records two sequences of rhythmite development that must be

the result of two floods. This suggests that the rate of

deposition of a rhythmite sequence may be very rapid--

measurable in meters per day. Any extended period of non-

deposition would have produced erosional features, such as

those shown in Figure D3-15. Significant erosion between

adjacent rhythmites is not seen at Cummings Bridge. It is,

however, seen between the two distinctly separate sets of

rhythmites.

Hammatt and others (1976) and BaKer (1978b) mention two flood

phases, evidence for which consists of two flood slackwater

deposits. Baker (1978b) notes that the St. Helens set IS'

volcanic ash is preserved in the younger of these two units.

Bjornstad (1980) provides confirmation of two floods which is

corroborated by this study.

The analogy between Flint's (1938) Touchet ueds and Bouma's

(1962) turoidites is clear. Ginsburg (1973) estimated the

velocity of a turuidite to be between 30 and 55 km/h (8.3 to

15.3 mWs). The term slackwater deposits, possibly originally

coinea by Allison (1933), hardly seems appropriate under these

circuinstances.

Clastic dikes that range from a few millimeters to several

meters in width are common in most exposures of the Touchet

deposits. The nature and origin of these dikes are discussed

in detail in section 5.

3.5.2.3 The Pasco Gravels. Brown (1975) referred to Bretz'

flood gravels in the Pasco Basin as the Pasco Gravels. This

facies of the late Pleistocene flood deposits mainly consists

of poorly sorted sub-rounded to sub-angular gravel, cobble-

and boulder-sized fragments, and minor amounts of sand.

Basalt is the dominant lithology present, but others, such as

.Svp I 0 / ?lWoodward-Clyde Consulta

S. Diagenetic clastic dikes are those in which the

existing clastic dike has been altered by diagenetic

modifications.

5.3 Clastic Dikes of the Pasco Basin

5.3.1 Previous Work

Jenkins (1925a) believed that the clastic dikes of eastern

Washington were produced when cracks resulting from earthquake

disturbances were filled with sediment injected under pressure

in an aqueous environment. He felt that the dikes could be

filled from the top and that they would die out at depth.

Lupher (1944) presented a thorough investigation of the occur-

rence and mode of formation of clastic dikes particularly as-

sociated with proglacial deposits in Washington and Idaho. He

recognized that the dikes were being produced concurrent with

the deposition of the host units into which they were em-

placed. At least four processes were involved in the filling

of the dikes, any or all of which may have been involved in

the formation of any individual dike. All of the processes

involved filling from above, or movement of sediment through

groundwater.

Lupher (1944) noted that the open fissures into which clastic

dikes were formed could be created in a number of ways. One

of Lupher's principal conclusions was that the clastic dikes

found in this area must be related to frozen ground or ice and

are therefore Pleistocene in age. Three of Lupher's five pro-

posed mechanisms for the creation of the fissures involved ice

indirectly: (1) uneven settling of and ultimately cracking of

blocks of sediment overlying layers of melting buried ice;

(2) gravity sliding and faulting on inclined zones of sub-

*-p P / oh/ss/ StWoodward.Clyde ConsultantsWvsPSS he <dl4-

surface melting; (3) formation of cavities where ice blocksand layers melted. The other two postulated mechanisms

involved erosion by underground streams, and faulting and

fissuring Dy landslides in the Columbia River basalts.

The possibility that clastic dikes were formed suo-aerially

was examined but discarded as a general method of formation,

because many dikes contain medium and even coarse sands that

could not oe transported aerially. Lupher (1944) likewise

discounted injection fromn below because he could find no

evidence of plastic or water-charged sediment being injected

from Delow. He also noted that many dikes were traceable to

overlying current-bedded sand.

The idea tnat clastic dikes might nave formed cataclysmically

at the time of deposition of the Touchet beds was rejected by.

Lupher, an antidiluvianist. A geologically instantaneous

flood would not have provided enough time for the formation

and subsequent melting of ice layers, which Lupher regarded as

prerequisite for the creation of the fissures into which

clastic dikes were emplaced. Lupner could neither believe

that clastic dikes containing up to a maximum of 80 dikelets

could oe related, other than marginally, to earthquake activi-

ty in the Pasco area.

Newcoino (1962) investigated the dikes described oy Lupher

(1944) and added a number of observations pertaining to their

mode of origin:

1. Some dikes occur in polygonal networks that have cell

diameters ranging from 15 to 120 m.

2. The dikes are most profuse within the altitude range

of 120 to 240 m and are scarce above 300 m.

-STU / I /,pb1 IWoodward.Clyde Consptants\PPpss Hq4izdo+

3. Dikes are most numerous where the Touchet beds

overlie highly permeable materials.

4. Dikes typically have 'roots", a "trunk", and

"branches" near the top.

5. The dikes cut all but the uppermost 3-6 m of the

thickest sections of the Touchet beds. I

6. The silt laminae on the walls, the 'wall seams" of

Lupher (1944) or 'clay skins" of Black (1979), are

filter cake, which attest to outward filtration of

sediment-carrying fluids from each successive dike

latina.

Newcomb (1962) concluded that the aoove features indicate that

the clastic dikes were formed by the upward injection of

groundwater. Each "dikelet" was probably caused by bank stor-

age when a pressure difference was produced by large drawdowns

of Lake Lewis, the large body of water ponded upstream of

Wallula Gap during the Missoula flood. Lowerings subsequent

to the first one caused injection along preferential planes of

weakness. Thus, the clastic dikes formed during the first

lowering of Lake Lewis.

Alwin and Scott (1970) noted that clastic dikes in the Touchet

Deds penetrate downwards from a few centimeters to over 30 m

with near vertical dips. They identified features of clastic

dikes, such as composite nature, clay wall linings, cross-

stratification, graded beds, and oriented grains. Alwin and

Scott concluded that these features indicated a downward in-

filling of the dikes by silt and sand. They felt that the

dikes represent infillings of permafrost-related crevices.

STe / /ob-s/s9Woodward-Clyde Consultants

Black (1979) made a detailed study of clastic dikes in the

Pasco Basin for Rockwell-Hanford Operations. He visited ten

different sites and concluded that the dikes are multigenet-

ic. He considered that previously suggested mechanisms, such

as earthquakes, dessication, deep frost cracking, thermal

contraction of permafrost, and upward injection of groundwater

are not the primary modes of formation of most cracks.

Neither did he discount the possibility that some or all of

these mechanisms could have been used to produce some of the

cracks. Black observed that the bulk of material filling most

observed dikes came from above during aperiodic and repeated

widening and concurrent filling of cracks in an aqueous envi-

ronment. In seven of the ten observed localities, all of the

dikes were composite (Hayashi, 1966) and were filled from

above in a stress environment that indicated tension, not

compression.

BlacK (1979) hypothesized that hydraulically danmed late

Pleistocene floodwater, which repeatedly covered the area, was

responsible for the formation of the fractures. - for the

aperiodic widening of these, cracks - and was the primary

source of material that filled the cracks. Sudden loading by

floodwater on a ground surface whose ground-water level was

not close to the surface produced stresses that were irregu-

larly distributed. These stresses induced cracking of the

ground, which would have allowed turbid water to enter.

Sediment in the water would at first have been filter pressed

against the walls of the crack, creating the clay skins."

Fractures could have been widened as the load increased or as

shear resistance decreased with increasing pore pressure.

Continued widening of the crack would have permitted coarser

sediment to enter. The flow of sediment-laden water along the

length of a crack would have produced the foreset-bedding

structures frequently seen.

STVP I /o//gWod~ward-Clyde Consufat

V e @SS 4-J~

Of the remaining three localities studied by Black (1979), one

(site 3: on the Old Inland Empire Highway in section 9, T9N,

R25E) had indications of a tectonic origin for the fractures;

another (site 6: near Richland City landfill, SE 1/4 section

20, T20N, R28E), having a polygonal dike arrangement, was not

similar to any other, and no origin was proposed for the frac-

tures; and the last (site 9: SE 1/4 SE 1/4 section 19, T9N,

R27E, a borrowpit near Kiona) was deemed to contain dikes that

were not considered to be typical clastic dikes--simply col-

lapse of material into a fracture generated by slope fail-

ure. Using Hayashi's classification, the majority of Black's

dikes would be composite, injection or composite, infilling

clastic dikes.

Summary - Previous Work

All previous workers recognize the close relationship between

the deposition of the Touchet beds and emplacement of the

clastic dikes. Most invoke mechanismns for the formation of

the dikes that have characteristics peculiar to both the

Pleistocene (ice) and/or the catastrophic floods (water).

Only JenKins (1925a) proposes an earthquake source for the

original cracks. Black (1979) does not discount earthquakes

as a possible source, but notes that the almost ubiquitous

presence of clastic dikes in the Touchet beds would have

required a far greater level and a more widespread

distribution of seismic activity than has been recognized so

far.

5.3.2 This Study

Clastic dikes were observed all over the Pasco Basin during

this study. In most cases the dikes were in Touchet beds. No

clastic dikes have been observed in the Ringold Formation,

although Grolier and Bingham (1978) report one such occur-

,, . I * roWoodward-Clyde Consultantsupr PP3 IR - dok{

rence. In the non-Touchet cases, clastic dikes were observed

in basalt and pre-Palouse loess. The Touchet dikes seen fit

almost exclusively into Hayashi's composite category: Doth

injection and infilling types. The dikes seen in basalt were

simple. In one case the clastic dikes were intensely

weathered and probably predate the late Pleistocene floods.

The otner clastic dikes in basalt were probably late

Pleistocene.

Selected clastic dikes observed during this study are

described in Appendix B.

The principal observations made in this study regarding the

formation of clastic dikes in the Pasco Basin and associated

valleys are that:

1. No clastic dikes penetrate unequivocally eolian

deposits of Holocene age (This suggests a sub-aqueous

development of most of the clastic dikes.).

2. The vast majority of clastic dikes occurring in the

Pasco Basin and vicinity occur within the slackwater

Touchet beds. However, *Touchet" dikes have been

seen in basalts and pre-Palouse soils whose ages are

far older than the 13 ka of the Touchet beds. Dikes

have also been reported in the upper Ringold

Formation. In all cases the dikes occur below the

maximum level of the floodwaters, approximately

350 m.

3. The composite OTouchet" clastic dikes were formed

during the deposition of the Touchet beds. The many

examples of truncated dikes overlain oy more Touchet

sediments confirms this idea. Bedding-plane slippage

occurred within the Touchet beds coincidentally with

5m-P / lob-s/&VWoodward-Clyde Consultants\NPPSS

the development of some of the clastic dikes.

4. Evidence has been found at the Cummings Bridge

exposure for at least two major floods of late

Pleistocene age. The rhythmites contained in the

Touchet beds deposited by these two major floods do

not represent numerous individual floods of suffi-

cient size to have filled a lake the size of Lake

Lewis. Instead they represent pulses into an exist-

ing lake. If Baker's (1973) conclusion about the

duration of the last late Pleistocene flood is cor-

rect, then deposition of the Touchet beds and the

formation of the enclosed clastic dikes must have

occurred in a matter of weeks.

5. The time required for the deposition of the entire

flood deposits was so short that freeze-thaw wedging

of fissures or sub-aerial dessication could not hdve

produced the numerous composite dikes. The ice-

related clastic dike in tidal flats in northern

Canada (Dionne and Shilts, 1974; Dionne, 1976) are

features measurable in decimeters, not decameters, as

in the Pasco Basin.

6. most of the clastic dikes in the Pasco Basin taper

downwards and were filled from the top. Instances of

filling from below have been cited by Newcomb (1962),

Black (1979), and in Appendix B, but there are few of

these cases.

7. Aoout 5 cm of slip along a fault occurred during the

time of the late Pleistocene floods, as evidenced by

slickensided clastic dikes and displaced basal flood

deposits at Gable Mountain (Golder Associates, 1981).

STsP / I v4h51LWoodward e q Consultants\/JPPS55 14cidoLt

Muir and Fritsche (1981) described earthquake-related

features formed in sediments in California during the

1979 Imperial Valley earthquake. In saturated zones

complex dikes were formed, while in unsaturated zones

simple dikes were formed. This suggests that some

clastic dikes in the Pasco Basin may be earthquake

related. Woodward-Clyde Consultants (1980). in a

study of reservoir induced seismicity (RIS), noted

that man-made reservoirs that are either very deep

(>150 m) or very large (>1 x 1010 m 3) are the mostsusceptible to reservoir induced seismic events. The

ephemeral Lake Lewis, formed upstream of Wallula Gap

during the late Pleistocene flood from glacial Lake

Missoula, would have been both very deep (>250 m) andvery large (2 x 1012 m 3). The RIS study concluded

that seismic events were statistically more likely to

be triggered if there were active faults present in

the vicinity of the reservoir, and if the rate of

filling of the reservoir was erratic.

If Baker's (1973) hydraulic model is valid, LakeLewis both formed and largely disappeared within a

period of two weeks. It is conceivable that reser-voir induced earthquakes may have been associated

with the rapid filling and draining of Lake Lewis.

Shaking resulting from seismic activity induced by

the presence of Lake Lewis could provide a mechanism

for the sliding of blocks of Touchet sediments and,the fissuring of Pasco Gravels, pre-Palouse loess,

the Upper Ringold Formation, and basalt bedrock.

However, the abundance and widespread occurrence of

clastic dikes in the Pasco Basin, their composite

natures, and the realtively short interval during

which they formed all indicate that it is unlikely

Woodward.Clyde Consultants

wppss PundV JCkit

that earthquakes were the primary factor in their

formation.

8. The exposure at the gravel pit just northwest of

Kennewick shows a flat-lying composite Touchet

clastic dike penetrating a thick caicrete developed

on an older gravel (Figure D3-4). The dike is trace-

able near horizontally for over 5 m. No other such

fissures have been seen in calcretes such as this.

It is extremely unlikely that a flat-lying fissure

would remain open with over 250 m of water above it

while the clastic dike gently filled with sediment.

(Hydraulic injection of sediment appears to be the

most viable mechanism for the formation of this

clastic dike. If clastic dikes can penetrate indu-

rated carbonate-cemented conglomerate, then their

injection into loose, saturated silts and sands would

oe easy.)

9. Clastic dikes reportedly created in fissures opened

during folding in southern Chile (Winslow, 1977;

Bruhn, 1979) are not similar to the composite Touchet

dikes of the Pasco Basin. Their modes of origin

must, therefore, be dissimilar also.

Summary - This Study

The lack of clastic dikes in eolian deposits and the

predominance of clastic dikes in late Pleistocene flood

deposits strongly suggest that they formed at the time of the

flooding. This is confirmed by the frequent occurrence of

truncated clastic dikes being overlain by younger flood

deposits (Touchet beds).

Woodward-ClVde Consuftnts

Occasionally clastic dikes penetrate the entire sequence offlood deposits and extend downwards into basalt, Ringold, pre-Palouse loess and 200 ka cemented gravels.

High pressure injection is considered to be necessary toemplace dikes into the formations beneath the flood deposits,

and this mechanism is regarded as the most plausible for themajority of cases, at least in the early phase of a dike'sformation. Other processes, such as spreading of blocks of

Toucnet beds and liquefaction, presumably were also invoked as

Black (1979) suggested, to continue the growth of the number

of dikelets in a composite clastic dike.

2

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literature? If so, we and by shown?

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S- PSo $ 10EHITE FAULT

Location:

Distance toRRL:

Strike:

Dip:

Blue Mountains, Indian Ridge, T6N R38E

140 km (87 mi)

N to NE

Nearly vertical

Length:

Offset:

90 km (56 mi)

Early dip-slip movement followed by later strike-slip motion

Newcomb (1970):Kienle (1979):Kendall (1981):

normal fault - west side downlast motion dextral (< 1 km)last motion sinistral (< 1 km)

Time of LastMovement:

Capability:

Significance:

Young alluvium, Palouse and colluvium are not deformed (Kienle,1980). Last known offset in basalt occurred in approximatelyRosa time (13-14'ma)

Probably not capable (based on geologic evidence) - capabilityhas not been assigned or reviewed by the NRC.

The Hite Fault is not considered to be a significant seismogenicsource at Hanford for the following reasons:

1)2)3)

trend (N to NE)distance to site (140 km)non-capable (?)

References: 1) Kienle, C.F., and others, 1980, Geologic Reconnaissance ofParts of the Walla Walla and Pullman, Washington and Pendleton,Oregon 10 x 20 AMS Quadrangles, report prepared for U.S. ArmyCorps of Engineers, Seattle District, by Foundation Sciences,Inc.

2) Kienle, C.F., and others, 1979, Geologic Reconnaissance ofthe Wallula Gap, Washington - Blue Mountains - LaGrande,Oregon Region, report prepared for Washington Public PowerSupply System by Shannon & Wilson, Inc.

3) Kendall, J.J., 1981, the Geology and Structure of theBlue Mountains in Northeastern Umatilla County, Oregon,Draft MS Thesis, University of Southern California.

4) (Older work is incorporated by reference in the abovereports)

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LOE.^E'R SNAKE RIVER DAMS. McNARYANP MILL CREEK -

GEOLOGICAL AND SEISMOLOGICAL REVIEW

DEC 1901

5&'-J a Fae4ct 1q::?5`+eS -Lf3

4.1 HITE FAULT SYSTEM

The Hite fault system is a series of north-northeast-to north-

striking, strike-slip faults, which parallel the Blue Mountain trend from

the McKay Creek drainage north to the Mill Creek drainage (Figure 2). These

faults are largely confined to the north flank of the Blue Mountains, between

the Agency syncline and the Mill Creek-Hite fault-Duncan structures. They

form an en echelon pattern with an overall trend of N200 to 300E. From west

to east the major faults in the system include the Thorn Hollow, Saddle

Hollow, Ryan Creek, Peterson Ridge, Blalock Mountain and Hite faults. The

Thimbleberry Mountain fauilt strikes parallel to the Hite fault about 10 km

to the east. Several lesser faults with similar north to north-northeast

trends occur in the Deadman Pass-Emigrant Springs area and south of Bingham

Springs along the southern projection of the Hite fault. The Hite fault,

which is a much more prominent and complex structure than others in the

system, extends northeast of the study area for at least 60 km. However,

within the area, all faults within the Hite system appear to have similar

orientations, and are interpreted to have similar motions, as discussed below.

4.1.1 Hite Fault

The Hite fault is the easternmost and longest of the faults

within the Hite system. It extends from near the northeast corner of the

study area (Figure 2) along a gently sinuous trend south-southwest about

40 km to the South Fork of the Umatilla River (T3N, R37E). North of the map

area, the fault crosses the Touchet, Tucannon and Pataha Creek drainages

and extends to near the Snake River, about 50 km north of the study area

(Shannon & Wilson, 1973). Within the study area, the Hite fault is an ex-

tremely complex zone of faulting that ranges in width from a few tens of

meters to more than 1-1/2 km.

Portions of the Hite fault zone exhibit at least three generations

of gouge; and rock units of different ages appear to have different amounts

of displacement across the zone. Both of these phenomona suqqcst ep)isodic

movement of the fault. Although the fault is shown on Fiqure 2 as a discrete

trace, it actually consists of from one to several sub-parallel shear zones,

as well as drag folds and associated riedel shears (Tchalenko, 1970). North

of The Horseshoe (T5N, R38E), the fault bifurcates into a major and minor

NIPPss ¾~JQo¶+

strand. Similar patterns are suspected for other portions of the fault, but

have not been documented.

At its southern end, the Hite fault zone appears to dissipate

into a number of smaller faults. However, because this area is quite complex

and poorly exposed, the southern terminus of the zone has not been definitely

located. Several, east-dipping, dip-slip faults appear to take up some of

the motion south of Graves Butte (T3N, R37E). In addition, some of the

motion may be translated into the northwest-trending faults between Black

Mountain and Buck Mountain (T2N, R37E) and northeast-trending faults which

extend from Duncan (TlN, R36E) to Graves Butte.

The Hite fault zone is best exposed in the upper Walla Walla

River and Hill Creek drainages. Logging roads and natural exposures north

of Tollgate Chalet (SE 1/4, T4N, R37E) and on Indian Ridge (TGN, R38E)

reveal a broad 80 to 200 m zone of crushed, brecciated, and sheared basalt.

Much of the zone is cemented by chalcedony and stands in positive topographic

relief as a "china wall". Other areas within the zone consist of angular,

crushed, uncemented basalt with variable amounts of clay matrix. Well defined

zones of yellow, orange or red-brown silty clay, which appear to be finely

commutated basalt, cross-cut both the cemented and uncemented gouge.

In the South Fork of the Walla Walla River drainage, north of

Tollgate Chalet, few structural indicators of the sense of faulting are

evident. Those observed indicate oblique-slip; however, some small shears

within the main fault zone show sub-horizontal striae.

On Indian Ridge (T6N, R38E), the Hite fault consists of two

principal zones. The eastern zone, which appears to be the main zone, is

about 75 m in width and contains all three generations of gouge. The western

zone parallels the main zone, but it contains no cemented gouge where exposed.

Both zones contain three well-developed sets of shears, which are generally

expressed as silty-clay or finely-brecciated basalt gouge. The best de-

veloped set trends N100 to 150E, parallel to the Hite zone. These shears,

which are vertical or near vertical, form the main boundaries of the gouge

zone and also occur within the gouge. The second set is also near vertical,

but trends NS to 15 W. Shears on this trend originate within the gouge,

and in some places, extend over 1 km from the Hite fault (Figure 2). The

VV P PAV~d 0\

5i01O-P ;Ht 3

third set is poorly developed. It trends N45 to 600E and dips 65° to 7C W.These shears appear to extend as far as 100 m, or so, beyond the main zone.

Orientation of these three shear sets is consistent with the

interpretation that the most recent movement on the Hite fault was dextral

strike-slip. The N100 to 150 E shears represent both the main shear and

possibly some P shears (Tchalenko, 1970), the N50 to 150 W shears are reidel

shears, while the N450 to 600E shears are conjugate reidel shears, or tension

gashes (Hills, 1963).

Striae are well developed on all three sets of shears on Indian

Ridge along Tiger Creek Road (SE 1/4, T6N, R38E). Striae on the main

shears (N10° to 150E) are generally near horizontal, with a few inclined

as much as 150N from horizontal, where the shears dip west about 850. Our

interpretation of paleomagnetic data from Indian Ridge (Weston Geophysical

Research, Inc., 1978; Shannon & Wilson, 197 7c) shows the west side of the

Hite fault zone to be down. Thus the dip of the shears, the rake of striae,

and the sense of vertical offset are all consistent with nearly pure dextral

motion along the zone.

Striae on the N50 to 150 W (reidel) shears are also near horizontal

(0°-8 N) consistent with dextral motion on the Hite fault zone. The conjugate

reidels or tension gashes (M450 to 600E-trending shears) exhibit striae

which rake more steeply, generally from 250 to 45"NW. This is consistent

with a large normal component of movement, as would be expected on these

shears for dextral motion on the Hite zone.

The geometry of the three sets of shears favor nearly horizontal

dextral slip on the Hite fault zone. However, the large vertical offset of

Grande Ronde flows suggests a large component of dip-slip movement. On

both Indian Ridge (T6N, R38E), and in the South Fork of the Walla Walla

River, north of Tollgate Chalet (T4N, R38E), N-2 polarity flows arc juxtaposcd

with R-2 polarity flows, indicating vertical offset of over 100 m of the

Grande Ronde flows. However, the Frenchman Springs and Saddle Mountain;

flows, which overlie the Grande Ronde flows in the uplands of the Tollgate

Chalet (T4N, R38E) area appear to have only a few tens of meters of vertical

offset across the Hite zone. Thus, the small amount of stratigraphic data

available near the Hite fault zone suggests larger vertical offset of the

older Grande Ronde flows (15my) than of the younger flows. Such age variation

vJ~P~ ~Aot t @

shuTps

in the amount of offset could be explained by either: 1) continued st e-

slip movement of the Hite zone from post-Grande Ronde time to shortly after

Saddle Mountain time; or 2) normal, dip-slip movement in post-Grande Ronde

time, and post-Saddle Mountains dextral strike-slip motion. The first

alternative requires a relatively large amount of strike-slip, sufficient

to produce more than 100 m of apparent vertical offset. The inclinations

of striae measured suggest that at least 0.7 to 1.0 km of lateral motion

would be required. The second alternative requires no strike-slip motion

in post-Grande Ronde, pre-Saddle Mountains time, and a much smaller amount

of strike-slip in post-Frenchman Springs time. In addition, rejuvenation

of the Hite fault is consistent with the multiple generations of gouge

present along the zone. The favored interpretation is that the cemented

"china wall" breccia likely developed during an initial phase of predominantly

dip-slip movement which occurred in pre-Frenchman Springs time. The younger,

uncemented gouges, which cut the older breccia, were developed during dextral

movement of post-Saddle Mountains age.

4.1.2 Blalock Mountain Fault

The Blalock Mountain fault, as defined herein, extends from the

South Fork of the Walla Walla River north-northeast to the Kooskooskie

fault (sec. 29, T6N, R38E), a distance of about 13 km. The fault is best

expressed on the south side of Blalock Mountain (Figure 2) where it offsets

Grande Ronde flows (NE 1/4, sec. 10, T4N, R37E). Little is known about the

fault. In the South Fork Walla Walla River, the Grande Ronde flows appear

to be down on the east, suggesting dextral dip. No shear zone directly

observed; however, on the color infrared air photos, the fault appears as

a series of sub-parallel to en echelon shears, each from one-half to about

3 km in length and apparently striking slightly to the west of the overall

trend of the zone. Such a pattern would imply sinistral slip, at odds with

that suggested by the apparent stratigraphic offset.

The Blalock Mountain fault appears to die out south of the west-

northwest-striking Lincton Mountain faults. Its inferred juncture with

Kooskooskie faults is not exposed; however, the oblique sense of motion

measured (Figure 2; SW 1/4 sec. 9, T6N, R38E) on the eastern Kooskooskie

fault (right-later, west-side-down) is consistent with and compatible with

PP3SS HqnJ..4

, -- � V. -1 a- '.. -Ji I; 11, Ak

> ~~~~~~~~~STOPtS V;Ltf3i~~~~~~~~~~~~~~~~~~ 0f//

faults occur along, and parallel to, the Rattlesnake Wallula Linea-

ment (Section 3.2.2.3) which merges into the north flank of.the Horse

Heaven Anticline just west of Wallula Gap. South of Umapine and Touchet

(T5N, R53 and 34E), the amplitude of the fold is about 1,300 feet

(390 m). At Wallula Gap, it is less than about 1,000 feet (300 m),

while west of Wallula Gap, the anticline becomes more complex and

its amplitude increases to over 1,600 feet (480 m). The fact that

Wallula Gap occurs at a structural low in the Horse Heaven Anticline

is consistant with structural control of the course of the Columbia

River. The lowest structural elevation of the Horse Heaven Anticline

occurs, however, at its eastern end, south of the study area. There,

the maximum elevation of the top of the Columbia River Basalt is

about 1,600 feet (480 m) above sea level, as opposed to about 1,730 feet

(520 m) at Wallula Gap. Kienle and others (1979) suggest that this

may indicate subsidence of the east end of the structure since

establishment of the present course of the Columbia River through

Wallula Gap. This interpretation is consistent with the apparent

movements along young faults in the Wallula Fault System, which

trend west-northwest along the Horse Heaven Anticline's north flank

near Milton Freewater, south of the study area.

3.2 Regional Fault Systems

3.2.1 Hite Fault System

The Hite Fault System consists of a set of at least five major

3 north-northeast striking faults (Kienle and others, 1979). The system

extends from east of Pendleton, Oregon, along the northeast flank of

the Blue Mountains into southeast Washington. The largest of the faults

is the Tom Hite Fault, generally referred to simply as the Hite Fault.

It is the easternmost large fault in the system which bears its name,

3 and the only major fault in the system which extends into the project

area (Figure 1), near longitude 1180W, latitude 46*N (Plates 2

3 and 3).

£ South of the project area, in the Mill Creek drainage, the Hite

Fault is well exposed as a complex, major zone of faults whose most

g WP3 Hlmdou+

recent movement has been interpreted as right-lateral, strike-slip

(Kienle and others, 1979; Kienle and Hamill, 1980). Within the study

area, the Hite Fault is less well exposed, but it is relatively

easy to follow because of the generally large offset across it and

its distinct topographic expression.

From the south margin of the study area (Plate 3), near Paradise

Ridge, (T6N, R39E) northeastward to the Tucannon drainage (TION,

R41E), the Hite Fault is expressed topographically as a series of

aligned drainages and notches in ridges and spurs. Within this stretch,

the fault generally consists of a conspicuous main strand 300 to

1,000 feet (100 to 300 m) wide, and one or more parallel or sub-

parallel lesser strands which vary from less than 3 feet (1 m) to

at least 30 feet (10 m) across. North of the Tucannon River (TlON-

T11N boundary, R41E) the Hite Fault becomes a much less prominent

topographic feature, largely because of the thick cover of loess,

but also because of a decrease in apparent offset across the structure.

From Eckler Mountain (T9N, R40E) to the south, vertical offset

across the zone is about 600 to 650 feet (180 to 200 m) with the

northwest side down. Northeast of Eckler Mountain, the vertical com-

ponent decreases to about 200 feet (60 m) at the Tucannon River.

North of the Tucannon River, the apparent vertical offset of the fault

decreases, although there is evidence to suggest that vertical offset

of the Grande Ronde flows is larger than the few tens of meters ex-

pressed in the overlying Wanapum flows, as discussed below.

The Hite Fault System (Plate 3) is paralleled by west-facing

drag folds, a geometry consistent with the west-side-down vertical

offset. These drag folds are well-exposed where the fault crosses

the Touchet and Tucannon Rivers (Plate 3). Together the drag folds

and the vertical offset of the fault have a structural relief of

about 980 feet (300 m) in the south part of the area and about 600 feet

(180 m) south of the Tucannon River, based on the difference in ele-

vation of the top of the Grande Ronde Basalt (Vantage horizon) across

the fault zone and associated folds.

S5S H doA+

5ProS >t3

kQ/ts- /SCThe best exposures of the Hite Fault are along the Tucannon River

on the east canyon wall (NE 1/4 sec. 16, T1ON, R41E) and about 1-1/3

miles (2 km) to the northeast along Blind Grade Road (NW 1/2 sec. 10,

T1ON, R41E). There the main Hite Fault Zone is bounded by two parallel

gouge jones about 600 feet (180 m) apart. The western gouge zone dips

approximately 800E and averages about 20 feet (6 m) in width. It con-

sists of about 19 feet (5.7 m) of silica-cemented gray breccia and

about 1 foot (0.3 m) of yellow-brown clay-silt gouge on its west

margin. The clay-silt gouge has well-developed striae which rake

1O0N. At the Tucannon exposures, this western margin strikes N300E,

while to the north it curves gently northward to a N21°E strike on

Blind Grade Road.

The east boundary of the zone is less well defined, apparently

consisting of shattered basalt cut by an anastamosing network of east

dipping shears which strike between Nl500E and N300E, and dip between

55°E and 800E. Shears along the east boundary which have strikes

closest to that of the overall zone (N210E) have the steepest dips

(800E) and striae which are close to horizontal (rake 100N); shears

most divergent have the shallowest dips (as low as 55°SE) and the

steepest raking striae (up to 400N).

A small thrust fault (not shown on map) dipping 400N and strikingapproximately east-west also cuts the east margin of the Hite Fault

on Blind Grade Road. Although offset is only a few feet, the presence

of this small thrust is consistent with the other features described

above which suggest strike-slip motion.

North of the Tucannon River-Blind Grade Road area exposures, the

Hite Fault Zone is largely covered by thick deposits of loess and

colluvium. In Linville Gulch (center sec. 3, T1ON, R41E), the fault is

inferred to pass through a notch between exposures of Grande Ronde and

Dodge basalts located about 350 feet (110 m) apart. Offset of the

Dodge flow of the Frenchman Springs Member of the Wanapum Basalt appears

\Nves H cad ij

to be about 160 feet (50 m) down to the west, as compared to about

300 feet (90 m) approximately 1-1/3 miles (2 km) south. Together with

the apparent narrowing of the fault zone from about 600 feet (180 m)

at Blind Grade Road to about 350 feet (100 m), this suggests a rapid

diminution of total movement on the fault from the Tucannon River to

the north. Indeed, at Pataha Flat, about 3-1/2 miles (5.6 km) north-

northeast of Linville Gulch, the unfaulted Roza flow passes across the

trend of the Hite Fault.

Although no continuation of the Hite Fault was found through

Pataha Flat, two faults approximately on trend with the Hite Fault

were found north of Pomeroy in Tps12 and 13N, R42E. Both of these faults

cut Grande Ronde and lower Wanapum (Frenchman Springs) flows, but are

not known to cut the Roza flow. The first and southernmost of these

faults extends at least from the west end of the Ben Day Gulch Fault (NE

1/4 sec. 20, T12N, R42E) on a N100E strike, to Meadow Creek, 2 miles

(3 km) to the north. It is well exposed in cuts on the Gould City

Road (SE corner SW 1/4 sec. 9, T12N, R42E). The fault gouge consists

of about 15 to 17 feet (4.5 to 5.2 m) of indurated, brown, basalt

breccia in a brown-orange clayey silt matrix. Sheared and shattered

Grande Ronde Basalt extends at least 30 feet (9 m) on both sides of

the zone which, at this exposure, strikes approximately N50E to N10°E.

Horizontal striae occur at both contacts between the gouge and the

sheared basalt. No significant vertical offset of the basalt was

observed, consistent with the horizontal striae. The zone is cut by

several small vertical shears which strike N500W.

The second, northern fault extends from at least Meadow Creek

(NE 1/4 sec. 8, T12N, R42E) northward to South Deadman Creek, and is

inferred to extend along a photolinear striking N15°E to the northeast

of Gould City (NW corner sec. 21, T13N, R42E), a distance of about

3-1/2 miles (6 km). This fault is also exposed in cuts along the

Gould City Road (SE 1/4 sec. 32, T13N, R42E). Where exposed, it is a

shear zone striking N5E, which dips 860E to 880E. The zone consists

\U\NPP5i HanduA

$:Ties '- d 3

of 2-1/2 feet (3/4 m) of cemented red-brown breccia, with about 1 foot

(1/3 m) of coarse, indurated, rubbly, basalt breccia in a clay-silt

matrix on the west side of the zone. Well-developed horizontal striae

and grooves are exposed in the west wall of the fault. About I mile

(1.6 km) along the fault trend to the south, a small, east-west

striking thrust, dipping 18'N, is exposed cutting the Frenchman Springs

flows (NW 1/4 SW 1/4 sec. 4, T12N, R42E). The orientation and slip

of this small zone are consistent with strike-slip motion on the adjacent

fault striking N10°W.

3.2.1.1 Other Structures Related to the Hite Fault. Several

features were mapped which appear to be related to the Hite Fault.

These include two parallel monoclines which extend north-northeast

along the Hite Fault trend north of Tatman Gulch (sec. 23, T11N, R41E)

to near Pomeroy. Across the eastern monocline, which is an antiform,

the dip of the Roza flow increases from near-horizontal to about

1-1/20 to 20W. Across the western, synform monocline, dips decrease

again to near-horizontal. Net structural relief is about 100 feet

(30 m) on the surface of the Roza flow.

Also apparently related to the Hite Fault is a feature referred

to as the "Pataha synform". It consists of a tight, northeast-striking

syncline, which Is exposed at Pataha in cuts on Bell Plain Road

(SW1/4 sec. 35, T12N, R42E) and to the south in Benjamin Gulch (S1/2

sec. 8, T11N, R42E), and which opens southward into a northwest-facing

monocline as it nears the north end of the Hite Fault. At Pataha, the

fold strikes about N25'E; the west flank dips 13'SE, while the east

flank dips at least 200NW. At Benjamin Gulch, the west flank of the

"Pataha synform" dips about 8° SE, while the east flank dips only

20 NW. South of Benjamin Gulch, dips on the east flank flatten to

horizontal or to a slight westward dip near the Hite Fault.

Another feature related to the Hite Fault is the Linville Gulch

Fault, which appears to be a north-northwest striking splay of the Hite

Fault. It is inferred to extend along Linville Gulch (T11N, R41E)

fPSS 6 YJ oa

for a distance of approximately 5 miles (8 km). The elevation of the

base of the Dodge flow appears to be about 80 to 100 feet (25 to 30 m)

higher west of the gulch than to the east (sec. 33 and 34, TU1N, R41E).

A small gouge zone, possibly related to the fault, is exposed along

the Linville Gulch Road about 2 miles (3.2 km) north-northeast of the

Hite Fault (NE 1/4, SE 1/4 sec. 28, T11N, R41E). The gouge zone trends

approximately N400W and consists of 8 to 10 feet (2-1/2 to 3 m) of

loose basalt breccia in a clay silt matrix. Poor exposures did not

permit determination of the apparent sense of offset.

The Linville Gulch Fault was previously inferred to extend north-

northeast to the Central Ferry Fault (T13N, R40E) by Kienle and Newcomb

(1973). However, more detailed work conducted for this study shows

that the Linville Gulch Fault must stop south of Pataha Creek, where

flows can be traced unbroken across its projected trend.

Faulting along the Snake River (T14N, R42E) downstream from Lower

Granite Dam was previously interpreted to be an extension of the Hite

Fault (Kienle and Newcomb, 1973). This interpretation was based mainly

on prominent north-northeast trending topographic linears, which con-

tinue between Illia and Gould City, and the pinch out of the Frenchman

Springs Member in the general location of these linears. Mapping

during this study, however, suggests that faulting near Illia (Tps 13

and 14N, R42E) trends northwest and is related to the other small north-

west-trending faults in the study area, as discussed in Section 3.2.2.6.

3.2.1.2 Age and Offset of the Hite Fault. Because of the

well-expessed drag folds, large vertical offset and lack of good out-

crops of the fault zone itself, the Hite Fault has previously been

interpreted as a down-to-the-west, normal fault (e.g. Newcomb, 1970,

1965; Swanson and others, 1977). However, as described above, more

detailed work, examination of new borrow and road cuts along the

fault zone within the study area, and mapping to the southwest of the

study area (Kienle and others, 1979), document significant strike-slip

YPsS +crAo+

i s . ' - . _

on the Hite Fault between its southern terminus east of Pendleton,

Oregon, and the Tucannon River area. Observations along the fault

suggested to Kienle and others (1979) that dextral slip was the most

likely sense of offset. However, data developed by Davis and others

(personal communication, 1980) east of Pendleton, Oregon, may be

more consistent with left-lateral offset.

Age of the Hite Fault is also problematic. Although young alluvium,

the Palouse Formation and colluvium are not deformed by the fault, pre-

Palouse sediments whose age can be firmly fixed have not yet been

found across its trend. South of the area, the Hite Fault appears to

be older than faults of the Wallula Fault System.

Lack of faulting of the Roza flow at Pataha Flat was interpreted

by Newcomb (1970) as indicating that the Hite Fault ended at Tatman

Gulch, south of Pataha Flat. However, Kienle and Newcomb (1973)

later found evidence for faulting on trend with the Hite Fault, north

of Pataha Flat. They interpreted the lack of faulting of the Roza

flow at Pataha Flat to show that the youngest movement of the Hite Fault

was of pre-Roza age. Subsequently, Swanson and others (1977) found

offset of the Roza flow south of the Tucannon River in the Cahill

Mountain area (T9N, R40E) and revived the earlier interpretation that

the Hite Fault ends south of Pataha Flat, with the additional refinement

of two small monoclines. Thus, their mapping suggests that deformation

north of Pataha Flat along the Hite Fault trend could be associated

with the dying out of a normal fault into a west-facing monocline..

Two new lines of evidence are, however, at odds with this normal-

fault interpretation. First is the abundant evidence for strike-

slip motion on the Hite Fault, both in and south of the study area.

This evidence includes not only subhorizontal to horizontal slicken-

sides and striae, but the presence of conjugate shears located within

and extending from the Hite Fault Zone (Kienle and others, 1979).

Second is the local presence of small, generally east-west trending

Y^P~sS Hcand ovt

STOPS t 3

normal and thrust faults in, and emergent from, the Hite Fault one.

These faults show local elements of extension and compression parallel

to the main zone, and are similar to features found on many large

strike-slip faults elsewhere.

3.2.1.3 Central Ferry Fault. The Central Ferry Fault, as

defined here, extends from a quarry east-northeast of Dodge (SW 1/4,

SE 1/4 sec. 10, T12N, R40E) northward to the Snake River at Central

Ferry (NE 1/4 sec. 9, T13N, R40E), and probably extends across the

Snake River and under glaciofluvial deposits for a total distance of

about 10 miles (16 km). The fault is expressed as a linear topographic

depression and as notches in drainages and ridges. It is exposed in

roadcuts in lower Deadman Creek, along the new state Highway 127, and

in the above-mentioned rock quarry near Dodge, where it is intersected

by another fault which strikes N50°W. The measured strike of the gouge

zone in outcrops ranged from N5°W to N151W. Well-exposed striae rake

from horizontal to 110 N. The east side of the fault is down at Central

Ferry, which, together with the striae and low dips, indicates a

left-lateral sense of movement. Previous reconnaissance mapping (Kienle

and Newcomb, 1973) had inferred a connection between the fault ex-

posed at Central Ferry and the Linville Gulch Fault (Section 3.2.1.1);

however, the present study documented that such a connection does

not exist.

Gouge and shear zones observed along the fault are variable in

both width and degree of brecciation. At the exposure in the quarry

near Dodge, the fault consists of several small vertical shears, 2 to

10 inches (5 to 25 cm) in width, which cut shattered and jointed Dodge

flow in the north face of the pit. The fault is cut by an intersecting

N500W fault with 2-1/2 to 3 feet (0.5 to 1 m) of gouge. The small shears

lie along a linear north-south trending depression which continues

toward Deadman Creek and allows a tentative connection of this exposure

with the northern exposures of the Central Ferry Fault.

A linear mound or possible reverse slope scarp trending N50W was

observed in a tilled field of loess about 1 mile northeast of Housner

w9Pss Hcdow+

2

Reviewer k. ke ~ndkDate * _jI

/ O l~s/8GEOLOGY FIELD REVIEW CHECKLIST

1. Outcrop/stop identification. SI -o p- U~. _q

T7 V 1f37 EJ Sc- 3),2. Outcrop/stop description.

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BUROKER FAULT

Location: About 5 miles south of Buroker, T7N R37E, Sec 31.

Distance toRRL:

Strike:

Dip:

Striae:

Sense ofMotion:

Capability:

124 km

N150E

31°NW

Rake N30 0W

Reverse

May be classified as being capable; Pleistocene gravel,Palouse soil and reworked Touchet are displaced.

Reference: Kienle, C.F., 1980, Geologic Reconnaissance of Parts ofWalla Walla and Pullman, Washington, and Pendleton, Oregon10 x 20 AMS Quadrangles, report prepared for the U.S. ArmyCorps of Engineers by Foundation Sciences, Inc., Portland,Oregon.

vWep-s• I40may.co~

4 .a1 in kj~i-1Lm - --I /

Figure 78. SKETCHUnits present(same scale as

OF STRATIGRAPHIC UNITSin Buroker Fault exposurephoto 7A.)

with faults shown

Location: NW, SW,4

Strike: N150E

Dip: 310NW

Striae: Rake N30W

sec. 31, T7N, R37E

' La_|V^; ~. ,S

6 % FOUNDATION SCIENCES, INC.GEOTECHNICAL CONSULTANTS

PORTLAND, OREGON

wPepss H'4q o-iBUROKER FAULT

DATE 12/80 JOB NO. 148-1 FIG. 7tA~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~'

the basalt are caused by faulting or by a monoclinal fold, although

Newcomb (1965) shows the flexure as a buried fault. No surface

expression of the flexure was found during this investigation.

3.2.2.8 Prospect Point Fault. The Prospect Point

Fault is inferred to trend east-west along Mill Creek North of Pros-

pect Point Ridge (SE 1/4 corner sec. 15, T7N, R37E to SE 1/4 sec. 17,

TiN, R36E). The location of the fault (Plate 2) is closely fixed

by water well data (Newcomb, 1965), which show a measurable change

in the elevation of the groundwater surface across the fault. The

elevation of the top of the basalt also changes across the inferred

fault, with the south side about 50 to 100 feet (15 to 30 m ) higher

than the north side (Figure 6). Some of this difference may, however,

be erosional. No outcrops of the zone were found, so its age remains

unknown.

3.2.2.9 Promontory Point and Buroker Faults. The

Promontory Point Fault (Plate 2) extends east-southeast from the

Walla Walla Basin along the south side of Prospect Point Ridge onto

the flank of the Blue Mountains (Tps. 6 and 7N, Rs. 36 and 37E).

The west end of the fault was located by Newcomb (1965) on the basis

of a difference between groundwater temperatures in the basalt north

and south of the structure. Wells immediately south of the fault

have anomalously warm water, while those to the north have normal-

temperature or anomalously cool water. The fault extends from beneath

the alluvial fill of Russel Creek onto the Blue Mountain flank along

a prominent linear ditch that trends straight up the regional dip

slope into the Pikes Peak area (south of study area). The linear

is well-expressed on U-2 photos and in the topography, particularly

in the N 1/2 sec. 10, T6N, R37E.

The fault itself is not exposed; however, the apparent offset

can be observed in several places. Southwest of Kooskooskie (SW 1/4

sec. 11, T6N, R37E) along McKay Grade Road the fault juxtaposes a

I. '~h Lf - io/>s/s Vi

phyric flow of the Frenchman Springs Member (southside) with a Grande

I Ronde flow (north side). South of Prospect Point, Dodge flows (Eck-

ler Mountain Member), which are exposed at or above 1,309 feet t400 m)

| (MSL) along Russell Creek Road, are downdropped at least 250 feet

(76 m) south of the fault (Figure 6).

The apparent downward offset on the south side is probably not

a consequence of simple, normal faulting. This is suggested by five

small related faults exposed in cuts on Russell Creek Road (sec. 31,

T7N, R37E) about 5 miles south of Buroker. These faults are inform-

| ally known as the 'Buroker faults', after the name given one of them

by Farooqui (1980). The westernmost of the Buroker faults (center

KW 1/4 sec. 31) cuts two Dodge flows in a small borrow area on the

north side of Russell Creek Road. This fault was first mapped by

Swanson and others (1979a). Earlier mapping by Newcomb (1965)

noted the anomalous dips of the Dodge flow, but the shear zone was

not exposed until recently. The fault strikes N 30'E and dips 49°:1W.

It consists of a 2- to 3-inch (5- to 8-cm) zone of gray clayey

silt gouge, which has well-developed striae at both contacts, with

| the adjacent basalt. The striae rake 459N. The top of the Dodge,

a few yards east of the fault, strikes N 55°E and dips 40'NW. The

low angle between the fault and the flow top makes estimation of the

offset difficult, but, if the flow top exposed west of the fault is

the same as that to the east, then the apparent offset is normal,

with the northwest side down. If this assumption is correct, the

striae then suggest a right-lateral oblique slip.

About 1,850 feet (565 m) east of the westernmost "Buroker fault'

X another fault zone is exposed in cuts on Russell Creek Road (NW 1/4

SW 1/4 HE 1/4 sec. 31, 200 feet (60 m) east of 1/4 section fence).

j Two shear planes are present in the zone: one which juxtaposes cemented

tectonic basalt breccia with colluvial gravels and loess; and another,

opposite to the first fault, which cuts only the breccia. The first

4 of these faults appears to be the larger of the two. It strikes

35J 90approximately N 15E and dips 31aW.IW (Figure 7). The striae on the

contact between this shear and the footwall rake 30°NW. Basalt

breccia, on the west side, is juxtaposed with post-basalt sedi-

ments (old loess overlying gravels) on the east side. Thus, the

apparent offset (Figure 7) is that of a thrust, up to the west, with

a large component of left-lateral slip. The second, lesser shear

also strikes about N 15E; however, it dips about 30ESE, and its east

side is offset upward a few inches, forming a small, horst-like wedge

at the end of the upper plate of the thrust (Figure 7). The apparent

throw of the top of the basalt on the main shear is about 3 feet

(1 m) in the plane of the outcrop. Taking the orientation of the striae

(30INW) into account yields an estimated total throw of about 6 feet

(2 m).

Examination of this fault shows it to be the fault discussed

by Rockwell (1979, p. It-115); they interpreted it as cutting over-

lying gravels and an older loess", but state that it "does not deform

overlying, younger loess." A subsequent examination of the fault

by Farooqui and Thoms (1980) is less clear. Farooqui and Thoms

(1980, Figure 10) show a fault between the western-most 'Buroker

fault" and the thrust (SW 1/4 NE 1/4 sec. 31); however, their photo-

graphs (Farooqui and Thoms, 1980, Figure 12), are clearly of the fault

described above (in NW 1/4 SW 1/4 sec. 31).

East of the thrust fault, three other shear zones are exposed

in cuts on Russell Creek Road. Two are exposed in a borrow pit about

200 feet (60 m) west of the Junction of Russell Creek and Foster

Roads (NE 1/4 SE 1/4 NE 1/4 sec. 31). Both are exposed in the north

wall of the borrow pit as vertical zones of poorly-indurated orange-

yellow basalt breccia in a clayey silt matrix. The zones vary from

a few inches to about 1 foot (.3 m) in width, and appear to have

caused little or no vertical offset of the exposed Frenchman Springs

flow. The western fault strikes N 45OW, while the eastern fault

strikes due north. The easternmost "Buroker fault" is similar to

I -.

these two faults, and is exposed about 100 feet (30 m) to the east of

} them in a roadcut along Russell Creek Road, near the Foster Road. The

fault strikes north, is vertical and consists 3 to 6 inches (7 to

15 cm) of poorly-indurated basalt breccia in a yellow-orange clayey

I silt matrix. Large horizontal striae observed on the westernmost of

these three faults, together with the lack of vertical offset, sug-

1 gest strike-slip offset.

| The "Buroker faults", are all near the location of the Promon-

tory Point Fault (Kienle and others, 1979) inferred by Newcomb (1965)

based on the well data. The orientations and inferred or observed

motions on the "Buroker faults" are consistent with an origin as

secondary shears associated with dextral strike-slip on the Promontory

| Point Fault. Indeed, if the south-down offset of the Promontory

Point Fault was consequence of normal faulting, it would be expected

that the "Buroker faults" would also be normal faults parallel to

the main faults.

Four of the five 'Buroker faults" cut basalt and are overlain

only by "young" loess; i.e. light tan eolian silt and fine sandy

silt, which is similar to the post-Touchet loess mapped as "loess

undifferentiated" by Newcomb (1965). This loess is very similar in

petrology to the Touchet beds, and appears to have been in large

part derived from them. The remaining "Buroker Fault", the thrust

fault in N.I 1/4 SW 1/4 NE 1/4 sec. 31, cats basalt, gravels, loess

and is overlain by unfaulted loess (Figure 7); it thus provides some-

what more information on the chronology of movement than the other

faults.

-The youngest material cut by the thrust fault in the "Buroker

faults' is the tan loess, derived from reworking of the Touchet

beds. As shown in Figure 7, only the lowest part of this loess is

faulted. Both the underlying brown loess (Palouse) and the gravels

X are cut in their entirety (Figure 7). The gravels consist of subangular

.

to subrounded pebbles, cobbles and boulders of basalt in a sandy silt

matrix (Figure 7). They are well-indurated but not cemented. Be-

cause of their composition, their position beneath the Palouse, and

their proximity to nearby outcrops mapped by N~ewcomb (1965) as .old"

or Pleistocene gravels, these gravels are also thought to be part ofthe 'old" or Pleistocene gravels of the Walla Walla Basin.

The offset of the materials cut by the fault is difficult to

measure because of the lack of exposure of unfaulted Dodge flow west

of the fault, and the syntectonic sloughing-ef the gravels from the

fault scarp. However, the offset of the Dodge flow is clearly greater

than that of the gravels, which is in turn, greater than that of the

loess. Thus, it appears that the offset occurred progressively over

a long time period, rather than in one episode. The youngest motion

must have been during Holocene time, since it cut materials reworked

from the Touchet beds.

No direct evidence is available for the age of the related

Promontory Point Fault. However, if one accepts the apparent genetic

relationship, then the motion on it must also be young. This con-

clusion is consistent with ages of other faults in the Wallula System

west and south of the area (Kienle and others, 1979) which cut Touchet

beds and post Touchet 7oess.

3.2.3 Service Anticline and Sillusi Buttes

The Service Anticline is a 26-mile (42-km) long, north-south

trending series of anticlinal segments. The structure emerges from

the regional north dip of the Blue Mountains Anticline north of the

Butter Creek drainage (sec. 4, TiN, R28E) at Service Butte, and is

inferred to continue along a series of small, isolated basalt knobs

northward to Umatilla Butte and Sillusi Butte. Previous mapping of

the structure was performed by Kienle and Newcomb (1973), and the

Sillusi Butte area was mapped by Anderson (Swanson and others, 1979).

About 2 miles (3 km) north of the Columbia River, the axis of the

structure bends sharply toward the northeast parallel to the Columbia

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SFcp _�_ /04sjFAULTED TOUCHET SEDIMENTS

Location:

Distance toRRL:

Description:

South of Umapine, T6N R35E

105 km

Touchet sediments and elastic dikes within the Touchet aredisplaced by normal faults. The faults strike N700 toN75oW and generally dip 300 and 600 north. Displacementgenerally varies from 2 cm to 50 cm with the north side down.Individual faults vary from 1 to 4 cm in thickness. Striaeare well developed and display rakes of N300E and due northfor the 300 and 600 dipping faults, respectively. Orienta-tion of the striae and apparent down-to-the-north displacementare consistent with dextral oblique-slip (Kienle, 1979).Kienle associates the faulted Touchet to the Barrett fault;a fault of the Wallula fault system.

Capability:

Source:

Based on the displacement of the Touchet sediments, the faultsmay be termed capable. However, the spatial and geneticrelationships of these faults to bedrock tectonic structureshave not been established.

Kienle, C.F., Hamill, M.L. and Clayton, D.N., 1979, GeologicReconnaissance of the Wallula Gap, Washington - Blue Mountain -

LaGrande, Oregon Region, report prepared for Washington PublicPower Supply System by Shannon & Wilson, Portland, Oregon.

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FINLEY OUARRY

Location: West end of-the Butte, T7N R3OE

Distance toRBL:

Strike:

Dip:

Striae:

Offset:

Time of LastMovement:

66 km. I

i

N60W to N70W for all three faults

South fault - nearly verticalMiddle fault - 60 - 890 SW-North fault - 40 - 700 SW

Nearly vertical to gently northwestward plunge.

Up to the southwest reverse faulting, less than 200 feet.

South fault - overlain by Holocene colluvium and loess. Timeof last movement vnkaown (pre-Eolocene). -

North and Middle faults: overlain by unfaulted colluvial depositsthat in turn are overlain by two caliche soil horizons. Uraniim-thorium dates on caliche rinds indicate that the upper soil isat least 70,000 years old. The degre of soil profile develop-ment (stage UI to III carbonate dev lopment) and the minitusage of. 70,000 years suggest that th',. upfer valeosol formed duringthe Sangamon Interglacial (oxygen isotope stage 5), which.lastedfrom 125,000 to 75,000 years B.P. By inference, the lower paleosolmay have formed during oxygen isotope stage 7 which lasted from251,000 to 195,000 years B.P. Thus, the time of last movementis at least 70,000 and may be as long as 200,000 to 250,000-years 3.?. .

Capability: Capable - NRC reviewers considered this zone subject to multiplemovements based on its estimated amount of offset and complexity.Based on the definition of capability in 10 CFR 100 Appendix Athis fault has been designated as capable.

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LOGS OF TRENCHESAT FINLEY QUARRY

Prepared for

Washington Public Power Supply System

Under the Direction of

United Engineers & Constructors, Inc.Philadelphia, Pennsylvania

December, 1981

Woodward.Clyce ConsultantsThree Embarcadero Center. Suite 700, San Francisco, CA 94111

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d-I rs 4 SToeP I O/ AG I V9Woodward-Clyde Consultants

CONTENTS -

Unit Descriptions

Straie Directions from FaultsExposed in Finley Quarry

Log of Trench at Finley Quarry

Log of Quarry Face at Finley Quarry

* NqPPSS Hoindout,

Pages 1-7

Figure 1

Sheet 1

Sheet 2

'-a.

Fo mop tslo 0UNIT DESCRIPTIONS

L Loess and reworked loess, massive silt with rare cobbles. The silt is brown(10 YR 5/3, dry) and very dark yellowish brown (2.5 4/2, wet). The unit is weaklyconsolidated and massive; is composed entirely of silt with occasional pebble- tocobble-size, subrounded-to-angular clasts scattered throughout the unit. The lowercontact is-an erosional unconformity. Silt has filled interstices where present inlower units.

Co-2 Colluvium, unconsolidated, angular basalt clasts in silt matrix. The clasts are cobblesof basalt in silt matrix with lesser amounts of granules and sand (<2% of the unit).The clasts are fresh with random orientations and no distinct bedding. Almost allclasts are derived from the Umatilla member. The matrix is brown (I0YR 5/3, dry)and very dark yellowish brown (2.5Y 4/2, wet). The lower contact is distinct withan erosional unconformity. The upper contact is gradational with unit L, loess.

Co-1 Weathered colluvium, poorly sorted, massive colluvium. Cobbles are nonvesicular,randomly distributed and range up to five inches In diameter. Matrix is clayey silt.Unit color is brownish yellow (2.5Y 6/6, dry) and dark brownish yellow (2.5 4/4,wet).

CL-1 Brown and black silty clay: This unit occurs in two colors: black in wedges in thefan-shaped top of the unit and in one stringer near the bottom; brown makes upthe rest. The black clay is black (5Y 2.5/1, dry) and black (5Y 2.5/1, wet). Thebrown is brownish yellow (2.5Y 5/6, dry) and brownish yellow (2.5Y 4/4, wet).

CL-2 Black day, dark gray (5' 3.5/1, dry) and very dark gray (5Y 4.5/1, moist). Theunit: is clay with clay with coarse sand to granule-size clasts making up -10%of tne unit; weathers massively, but is broken into pieces 'h- to %-in. long; hassubrounded pebble-, cobble-, and boulder-size clasts. The long axes of the clasts aresubparallel to the North Fault and form a crude foliation. The cobbles and bouldersare basalt, comprising -5% of the unit. The contact with unit CL-3 is undulatory,with unit 2, sharp and clear.

CL-3 Green clay, pale olive (5Y 6/3, dry) and (5Y 5.5/4, wet). The unit: is clay with aminor silt component; weathers massively; is non-resistant, breaks into pieces

%- to 1-in. long. Fabric and overall shape of the unit are parallel to the NorthFault. The northern contact with unit CL-2 is undulatory; the southern contactis the North Fault.

C-1 Calcified zone. This unit has great textural and lithologic variation, characterizedby development of calcification which decreases to the south. Based on the degreeof calcification, the zone has been mapped as two subunits, C-1 and C-la. Theupper portion, unit C-1 is highly calcified, white (1OYR 8/1, dry) and very palebrown (10YR 813, dry) to light-gray I00YR 7.5/2, wet). The lower portion,unit C-la is pale brown (l0YR 6/3. dry) and dark brownish yellow (2.SY 4/4,wet). Grain size within the unit ranges from areas which are composedpredominately of silt to those composed predominately of pebble- and cobble-sizebasalt clasts. The gravels are friable, massive and very poorly sorted. Clastsare angular to subangular and commonly float in a fine silt matrix. Allobserved clasts are derived from the Umatilla member. In the coarser grainedareas the calcification consists primarily of a coating of clasts. In the

UNIT DESCRIPTIONS (continued)

-\AjpfSS tk.J,,Jsilty subunits the calcification creates a platy texture. Clastic dikes are locallypresent. No tectonic fabric is apparent. Upper and lower contacts aregradational: upper contact with unit L is distinguished by an irregular colorchange; the tower contact is less distinct..

U-3 Compacted silt. Unit consists of three subunits: compacted silt, U-3; weatheredcompacted silt, U-3a; compacted silt with pebbles, U-3b. Units U-3 and U-3b arebrownish yellow (1OYR 6/6, dry) and dark brownish yellow (2.5Y 5/4, wet).Subunit U-3a, found near south end has reddish staining. Subunit U-3a is mottledwith brownish yellow (1OYR 616, dry) and yellow (0OYR 816, dry) and locally.yellowish red (SYR 5/6, dry) stringers. Subunit U-3 is nearly all silt, massive andindurated with planes of caliche developed subparallel to quarry face. SubunitU-3b has gravel stringers and packets. The gravels are massive, friable, andvery poorly sorted. Clasts are angular to subangular. All observed clasts werederived from the Umatilla member. Clastic dikes, %- to l-in. wide and up to4 ft long, generally steeply inclined and changing orientation abruptly, arefound throughout the unit. No tectonic fabric is present. Contact with unit Mis difficult to identify in places, sharp in others, and generally defined by thepresence of staining and/or mottling in M. Upper contact with unit U-4 isIrregular and marked by the presence of clasts and calcification.

U-2 Gravelly silt and silty gravel. Unit consists of very poorly sorted gravels andgravelly silts in which basalt, plutonic and metamorphic clasts float in a silt matrix.The matrix color is yellow-brown (2.5Y 5/4, dry) and very dark yellowish brown(2.5Y 3.5/2, wet). The lithology of the matrix varies widely, consisting of 40% to80% silt, 40% to 80% sand, and 0 to 20% granules. Clasts are predominatelycobble-size with approximately 10% boulder-size scattered throughout the unit.Approximately 90% of the clasts are non-vesicular, angular basalt. The remainderof the clasts are made up of approximately equal fractions of rounded tosubrounded vesicular basalt, and rounded clasts of granitic, andesite, schist, andquartzite. Bedding is poorly developed to the south and becomes better developedto the north. The lower contact with unit M is an erosional unconformity. Theupper contact with unit C-1a is gradational.

U-1 Poorly sorted, poorly consolidated gray gravels. Clasts consist predominately ofbasalt; Umatilla clasts are common. Non-Umatilla clasts are also common. Clastsare vesicular and non-vesicular, and range from rounded to angular. Diameters ofbasalt clasts range up to 1 ft. but the mode is 2 to 4 in. Quirtzite, granitic, andgneissic clasts are a rare but persistant part of unit U-1. These range from well-rounded to subangular. Maximum diameter is approximately 3-% in. Matrix of thegravels ranges from coarse sand to fine sand, and locally contains silt. The gravelsare locally crudely bedded; bedding is defined by changes in size. In the trench,the matrix color is yellowish brown (lOYR 5/4, moist) and (2.5Y 7/4, dry).

N-1 Unbedded, friable, poorly sorted, very fine sand clastic dike. The thickness of thedike is variable, ranging up to 4 in. Contact between unit N-1 and adjoiningunits is highly irregular in detail: it locally contains small fragments of claysimilar to the clay in the adjoining fault. One rounded, 1/5-in.-diameter redquartzite pebble is present within the dike. The sands contain muscovite as acomnmon accessory mineral.

Project No. IHnodFA14940 Hanford FSAR UNIT DESCRIPTIONS

Woowad-yde Cosuiltants 2 of 7

Frs9 Slop. IC? ;LG/Fq,

UNIT DESCRIPTIONS (continued) / HN-2 White silt with near-vertical layers of feldspathic sands. Sands contain muscovite.

N-3 Massive, friable, fine silty sand and sandy silt. Sand component includes predomi-nately quartz and/or feldspar. Muscovite is present but rare. Unit N,3 has a higherpercentage of silt and is slightly more indurated than unit N-1. Unit N-3 is awedge-shaped body that pinches out downward and reaches a maximum thicknessof 2 to 3 in.

M-5 Very poorly sorted, massive gray silty gravel. Angular to subrounded. basalt clastsin a fine sandy-silty matrix. Diameter of clasts range up to 3-4 in. Clasts arematrix-supported.

M-4 Poorly sorted, crudely bedded gravel. Clasts are subangular to subrounded.Diameters of clasts range from less than 1 in. to approximately 5 in. (Mode is1 to 3 in.). Umatilla clasts are abundant. The matrix is made up of coarse sand tofine pebbles. Bedding is locally defined by slight changes in the size of the gravel.The unit contains thin (generally less than 2 in.) lenticular fine sand lenses thatshow thin bedding. Color Is variable, but It varies from yellowish red (SYR 5/8,dry) to (5YR 6/8, dry). Locally, It shows darker patches of strong brown(7.5YR 3/5, dry). The gravel part of the unit is pale yellow (SY 8/4. dry)and dark yellowish brown (1OYR 5/4, wet). This color is better developed at thesouth end of the outcrop. Black bands of color are locally present. These aregenerally parallel to bedding.

M-3 Bedded silts and sands. This is a lenticular unit found at three locations along thequarry face. The southernmost location consists of interbedded white silts,lenticular sands, and rare lenticular pebbly gravels. The silts are white and coarse,and most are massive; however, the silts locally show thin bedding. Muscovite andbrown biotite are present. Sands are medium- to coarse-grained and gray in color.Most of the grains are lithic. Sand beds generally show no internal bedding andare normally less than 2 in. thick. Thin, lenticular pebbly gravels are present.Virtually all of the clasts in these gravels are basalt; however, two brown quartzitepebbles were present, and they were both well-rounded and less than %-in. indiameter. Within unitM-3, some very large basalt clasts lie within much finer units6nd commonly lie across bedding planes. The diameter of these clasts range from2 to 3 in. to as large as 20 in. x 15 in. They are normally subrounded tosubangular. The central unit M-3 lens is the smallest of the three. It consists ofcoarse white silt that exhibits abundant laminations. The laminations are locallydeformed around pebbles resting on top of the silt Small lenses (generally less than5 in. x 2 in.) of fine basaltic gravels are locally present. These contain isolatedclasts as large as 2-% in. x 1-% in. The northermost part of unit M-3 consists of whitesilts interbedded with thin pebbly sands. Enclosed within these finer-grainedsediments is one basalt clast that is approximately 6 to 8 in. in diameter.

M-2 Poorly sorted, massive conglomerate. Contains subangular to subrounded clasts ofbasalt; Umatilla clasts are common. No granitic or metamorphic clasts were observed.Diameter of clasts commonly is 5 to B in. One large boulder is 24 in. x 15 in.The gravel matrix consists of fine pebbles to coarse sand.

1Proje0 No. Hanford FSAR UNIT DESCRIPTIONS

Wd Icd W C 3 of 7

Rrs 57T0pUNIT DESCRIPTIONS (continued)

M-1 Angular basalt conglomerate, abundant Umatilla basalt clasts. Matrix color is verypale brown (lOYR 6.5/4, dry) and dark brownish-yellow (2.5Y 4/4, wet). MatrixIs friable and clasts stand out prominently above the less resistant matrix. Clasts arepebble- to cobble-size, are matrix supported and comprise approximately 35% ofthe unit. Matrix is predominately silt-size with a minor coarse component up togranule size. Granule-size matrix is found within a pod near the southern end ofthe unit. Clasts adjacent to Central Fault show no preferred alignment.

L-6 Clayey silt. Color is (2.5Y 6/4, dry) and (2.5 4/4, moist). Massive. Upper andlower contacts are clear.

L-5 Sandy gravel. Poorly sorted. The sand component is dominantly medium size,predominately basalt sand. Color is (2.5Y 6/4, dry) and yellowish brown (1OYR5/4, moist). Diameters of clasts range from % to 9 in. (Mode is 2 In.). The clastsare subrounded to rounded and Include both vesiculated and nonvesiculated basalts.Some clasts have weathering rinds up to 1/8-in. wide. The unit is massive with grossdepositional fabric defined by imbrication of clasts. The unit is slightly consolidated.Upper and lower contacts are clear. Phyric Pomona and aphyric Elephant Mountainclasts are present. No Umatilla clasts were observed.

L4 Silty clay with minor sand component. The silty clay color Is 2.SY 7/4, dry) andolive (5Y 5/4, moist). Highly plastic, minor scattered pebbles and cobbles. Thesand content is variable, and the unit grades from silty clay to sandy clay. Theunit is massive and is pervasively sheared. The shear planes are discontinuous andhave varied orientation. Due to abundance and discontinuous nature, these shearplanes were not mapped. The clay is highly susceptible to shrink/swell. A zone ofcolor change from olive to a slightly bedded-clay occurs subparaflel to the contactwith L-5, approximately 'A- to 1-ft wide. Thin (less than 1 in.) clastic dikes occurlocally.

L-3 Gravelly sand. The sand component is very fine, with minor silt and clay. Color ispale yellow (SY 7/3, dry) and olive (SY 5/3, moist). The gravel component issubrounded to rounded and ranges from 1 to 4 in. (Mode is 2 in.). The clasts arebasalt, including vesicular, non-vesicular, phyric, and non-phyric clasts. Theconcentration of clasts is highest in the lowermost 0.8 ft of the unit. Locallyclasts have thin weathering rinds. The contact with unit L-2 Is clear.

L-2 Very poorly sorted conglomerate. Loosely consolidated, poorly sorted. The matrixcolor is (2.5Y 6/4, - 7/4, dry) and (2.5Y 4/4, wet). Poorly sorted, fine to very finesand with significant amounts of day and silt. Medium to coarse sand grains ofbasalt are common. The larger sand grains are subangular to subrounded. The clast.-range in size, pebbles (0.5 in.) to boulders (15 to 18 in.). The modal size is 4 in.The clasts are basalts from Pomona and Elephant Mountain formations. NoUmatilla clasts were observed. Clasts larger than 2 in. generally have well-developedweathering rinds (up to 0.5-in. thick). The matrix comprises from 80% to 30% ofthe unit. The unit is massive with subtle depositional fabric that has an orientationof N60W ION. The fabric includes slight imbrication and lenses of clay, sand,and gravel.

Project No.| 14940 | Hanford FSAR | UNIT DESCRIPTIONS

W| od, WMd-Clyde CormntUftS 4 of 7

Fws~/- CobfUNIT DESCRIPTIONS (continued)

L-1 Clayey silt to clayey fine sand. The color of the silt component ranges from olive(SY 5/4) to pale yellow (5Y 7/3. dry) and olive (SY 5/3, moist). The color of thesand component is pink (SYR 7/3, dry) and (2.5 5/4, moist). The silt componentis expansive and sticky. Discontinuous shear plane with random orientations are

-- . common. Minor subrounded to rounded pebbles and cobbles are predominantlyPomona basalt. Massive upper and lower contacts are clear.

2H White tuff. The color is white to light gray (5Y 7.5/1, dry) and pale olive (5Y 6.5/3,wet), and has smaller areas of reddish-yellow (7.5 YR 7/6, dry) and reddish-yellow(7.5 YR 5.5/8. wet). The unit is friable and breaks into small poorly induratedplates. The unit is approximately 95% fine grained (predominately silt-size) ash withapproximately 5% dark minerals which commonly occur as concentrations longbedding(?) planes. The unit locally shows straited surfaces.

2G Weathered and sheared basalt. This unit is a highly weathered basalt which islocally spheroidally weathered. The spheroids make up approximately 30% of theunit. The more deeply weathered material between the spheroids is predominatelysilty clay in size (approximately 90%) with a minor sand component. Unit color isdark yellowish brown (00YR 4.5/6, dry) and dark yellowish brown (IOYR 3/4,wet). The uppermost part of the unit exhibits abundant fractures that are generallyparallel to the contact with unit Co-1. These fractures commonly exhibit polishedsurfaces.

2F Unit 2F consists of three distinct units described separately as 2F-1, 2F-2. and2F-3.

2F-1 Basalt granules in a weathered silty matrix. This unit consists of vesiculated,subrounded basalt granules in a silty matrix. The granules comprise approximately85% of the rock. Color is dark yellowish brown (2.5Y 4/14, dry) and darkbrownish yellow (wet).

2F-2 Basalt breccia. Unit consists of subangular to subrounded basalt clasts in apredominately silt and minor clay matrix. Clasts are both vesicular and non-vesicular, range from granules to cobbles, and are concentrated in pods. Color isyellowish brown (2.5Y 5/6, dry) and dark yellowish brown (2.5Y 4/4, wet).

2F-3 Basalt breccia with pink matrix. Unit consists of predominately basalt clasts in afine matrix. Clasts are almost exclusively basalt with less than 1% composed ofquartzite, tuff, and greenstone. Matrix ranges from silty clay to granules in sizewith silty clay being the mode. Clasts are randomly distributed and soww nopreferred orientation. Color is yellowish brown (1OYR 6.5, dry) and darkyellowish brown (1OYR 4.5/4, wet).

2E-2 Brecciated Pomona basalt. Same as unit 2E-1 except no boulders are present.In addition, its color Is all gray (BY 5/10). Unit contains clasts of fine grainedclastic material identical to unit 2E-1.

2E-1 Brecciated Pomona basalt. Rounded vesicular basalt cobbles and rare boulders ina matrix of basaltic pebbles, granules and coarse sand. Cobbles compriseapproximately 10% of the unit and are present in the lower and middle parts of

Project No.14940 Hanford FSAR UNIT DESCRIPTIONS

Wkodwcr-MV Consults 5of 7

I ED

:h

UNIT DESCRIPTIONS (continued)

the unit. Two cobbles of fine grained clastic material are present in the unit.These exhibit thin columnar joints, approximately 6 in. long and nor more than1/3 in. in diameter. The matrix makes up approximately 90% of the unit andexhibits mottled blue and salmon colors. Matrix colors are pink (7.5YR 7/4) andgray (5Y 5/1, dry) and strong brown 17.5YR 5/6) and very dark gray (5Y 3/1,wet).

2D Vesiculated Pomona. Large, subrounded vesicular clsts of Pomona basalt in aclastic matrix. Clasts range up to approximately 17 in. in diameter. Clasts aresubrounded and vesiculated. Vesicles range from 1/16 to 1/2 in. in longestdimension. The matrix makes up approximately 10% of the rock and is composedof clay, silt, fine, medium, and coarse sand; granules and pebbles with the clay-to-sand portion making up approximately 75% of the matrix. The matrix is brownishyellow (10YR 7.5/8, dry) and yellowish brown (10YR 5/8, wet).

2C Brecciated Pomona basalt. Predominately unvesiculated, subrounded to subangularclast of Pomona. Diameter of clasts range from less than 1 in. to 4 in. (Mode isI to 2 in.). The breccia is matrix-supported, which consists of silt-sized materialthat is predominately pale-yellow and cream colored.

2B Brecciated Pomona basalt. Lower part of the unit sbows abundant vesiculatedangular clasts of Pomona basalt clasts. The clasts display small vesicles that aregenerally less than 1/10-in. diarneter. §Thmeter of clasts range from less than I in.to approximately 1 ft. (Mode Is 2 to 4 in.). Matrix in lower part of unit 2Bconsists of silt-sized material, is mottles red-brown, yellow-brown, and creamcolored, and is probably palagonized. Rae black glass fragments present withinthe lower part of unit 26. Upper part of unit 26 displays predominatelyunvesiculated clasts, but the matrix maintains the yellow-brown to cream colorof the lower part of the unit.

2A Highly fractured Pomona basalt. Very similar to unit 2 but unit 2A contains morematrix (30% to 40%). In addition, lasts In unit 2A are smaller than those inunit 2, ranging from 'h to 4 in. in diameter. Clasts are both vesiculated andunvesiculated and vesiculated clasts are characterized by very small vesicles(<1/8-in. diameter) and by a low density of vesicles. The matrix is predominatelyfine sand with scattered subangular to subrounded coarse sand grains. Matrix coloris pale brown (10YR 6/3, dry) and (2.5YR 5/4, wet).

2 Highly fractured Pomona basalt with a fine sand and silt sized matrix. Angularclasts of Pomona basalt which show lath shaped phenocrysts to 1/8-in. in diameterin a fine grained black ground mass which weathers to medium gray. Clasts rangefrom h to 18-in. in diameter with a modal size of 3 in. Many clast edges areconcordant and may have once fit together. Matrix is composed of fine sand andsilt and makes up 20% or less of the unit. The color of the matrix is (2.5Y 6/4,dry) and (2.5Y 4/4, wet). Clastic dikes to Win. thick are locally present.

Is Closely fractured Umatilla basalt. Fractures spaced less than I in. apart and areapproximately parallel to the contacts between unit 16 and units 1A and 1.

Project No.14940 Hanford FSAR UNIT DESCRIPTIONS

Woodward-Myce Cornstats 6 of 7

.-6

Ft �4 S+0pUNIT DESCRIPTIONS (continued)

* ~WPPS- 4HindouA1A Angular to subangular clasts of Umatilla in a carbonate matrix. Diameter of clasts

range from less than I in. to 3-'% in. (Mode is 1 to 2 in.). Clasts are commonlyrmatrix-supported. The unit is generally massive and does not show well-developedanastomising clay seams or aligned clasts. The lower part of unit 1A displaysincreasing amounts of clayey-silt matrix.-This material replaces the carbonatematrix exposed higher in the exposure.

I Umatilla basalt. Very fine-grained aphyric black basalt, nonvesicular, jet black onfresh surfaces, dark red-brown on weathered surfaces. Commonly has broad,conchoidal fractures and irregularly shaped hackly columnar joints (C 1 ft. diameter).Outcrops have subhorizontal changes in weathered color (brown to black). Thelong axes of columnar joints are approximately vertical.

Project No. Hanford FSAR

14940 1 UNIT DESCRIPTIONSWoodwwCyde Conuft.ft 7 of 7

Fir4I 7s~

WPF

N

a

W

EXPLANATION

S a South Fault

M a Middle Fault

N a North Falut

Note: Striae for which fault planes are notshown were measured on surfaces whichtrike between N5SW and N7hW and dip

greater than 600.

Project No. Hanford FSAR STRAIE DIRECTIONS FROM FAULTS14940 HWoodwa rd- 'tyde Cors"Altmft EXPOSED IN FINLEY QUARRY Figure 1

6* Th.

J..

`7

EXPLANV.

k7'� c;c Z, a Mediuin'sa

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sandy"silt. j),eb

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S. /~~~~~~~~~~~~~~~~

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- - - - ~~~~~ -- -~~Clay 2

~~~~ ~~~~~~~~~tcgast~~~~~~~~~~~~~SAMP LEE K

B~asalt clast -

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in feet~~~~- ~ -

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90

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~~~~~~~~~~~~~~-7: JI -- . - : . e 4 .- - \ - w

, ,. , .- -- S .; ,-: -, < > ~EXPLANATION

- e - :- - ' :- ,,, - - - .e-; ;-. '- ' y/; Ts~in (less than l1in. thick) discolored :'. - ' .. . ., ' -. ., tr ."', j _:, .' 'live drab. clayerc oe

- .. . * .-;;- . .; 2. ~~~~~~~~~Polished and striated elay %earns

; ; e_,,t , ,,, X t;' > ii ' '; ' ;;; ; ; ' >-~~

fED S; X DD-Y99R~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.o-tw L~~~~~~~~~~~~~~~~~~~~~~~~~~~

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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~Bas ai0'te Cb''

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<'o''ffi'''g __ ; I Qary t 'jA

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2

-Sa f~ - -%Reviewer 444 SDate (O/1Z41/ o



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V/2lVI cZ4 f c b

'I/,77,

1190

a

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Fof l%

SOURCES: Kienle and others 11979. 19811Swanson and others 11980)

0 3 6 9 km.. . .~~~~~~~~~~~~~~~~~~~~

EXPLANATION

* Fault: dashed where inferred, dotted whereconcealed. 1ell on downthrown side.

Anticline arrows indicate direction of diD. and plunge; dashed where inferred, dotted

where concealed.

Syncline: arrows indicate direction of dip. .. and plunge; dashed where inlerred. dotted

where concealed.

If Project No. HnodFAProject No. | Hanford FSAR LOCATION MAP Figure

Woodward Clyde Consuttants

\A/PPSS )404o

ReviewerDate 44 , F 4E

f


1. What area does the map cover?Tu7i Wj' f40

0~~040 < 30~~~0 ,2&2. What type of map is it? What is

o-1 . I-

060�

7 -� X e 0, Y�' -�e �'ga;:� ( ~ / �"- /0-.

V I^0/0=An-,

3 h Id 0th3. Who did the I

&MIC-pe_i4. What is (are) prominent feature(s) shown to date?

6 r lit I~. ?P/elsi aez

5. Why was this mapping project undertaken and when was the mapbegun/completed? ;

pla��4�

IL

/31�Il/ Wf Af -46(e I6 //91/


* Jo , In, -a& . * ee ~ 4

7. When is the map to be published? In what publication series?already published, when and in what document?

kAt I I 4

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lb*.

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p iv dccfet - nrc.gov · 2 reviewer k w l"k date fiel? c geology field review checklist 1....

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