California Geology Magazine August 1990

8/7/2019 California Geology Magazine August 1990

http://slidepdf.com/reader/full/california-geology-magazine-august-1990 1/24



APU8L1CATION OF THEDEPARTMENT Of CONSERVATIONDIVISION OF MINES AND GEOLOGY

Stal.olCaM",n,a GEORGE DEUKMEJIANGoVllf/ lO.

The Resoorces Agency GORDON K VAN VLECKSecrelary for Resovrces

In This Issue IAEG 33RD ANNUAL MEETING . 170

COASTAL CONFERENCE . 170

GEOLOGICAL REMOTE SENSING CONFERENCE 170

SEA CLIFF EROSION . 171

HUNGRY VALLEY FORMATION. LOWER MEMBER DEPOSiTION 178

CALIFORNIA GEOLOGY EDITOR·IN-CHIEF RETIRES 184

SURVEY OF CALIFORNIA GEOLOGY READERS . 185BOOK REVIEWS •.•..•.... . 187

MAIL ORDER FORM •.. .189

CALIFORNIA GEOLOGY SUBSCRIPTION FORM .190

RESOURCES FOR EARTH SCIENCE TEACHERS .191

MEMORIAL-DR. ADOLF PABST. .192

CALIfORNIA GEOLOGY sial!

Oepa,'ment 01 General ServicesOUoce 01 Slal(l Pnntlng

OejIarlmenl 01 Cooserval,on

Graphics and DeSign:Publicallons Supervisor:

RANDALL M. WARDlJ,rocIO'

JAMES F DAVISSiale Geoklglsl

Don Dupras

Louise Huckaby

Jeff Tamberl

Cove r: Examp le o f s ea cliff erosion a long the Cal if ornia coast . Shore li ne

retreal is a continuing natural geologic process along 86% of the 1.1OO·mile·

long California coast. Waves, t ides. wind, rain, and waler runoff from human

activities combine to wear down and reshape sea cliffs. Allhough consider·

able money and ellort is spent on protecllve structures-such as concrete

seawal ls . wooden seawal ls, gabions. and r ip·rap-Io withstand di rect wave

attack, such slructures eventual ly fail over geo logi c l ime. Engineers com

monly bui ld wel l-devi sed protect ive s truc tures w ith des ign l ives of 20 to 25

years. This considerat ion is somet imes overlooked when planning long-term

cl if f top st ructures along California's coastline. An ar ticle about this problem

starts on page' 71. Photo by Robert Norris.

Geological

Remote Sensing Conference

Oov,SIOtl He&OQuarl(l'S: 1416 N,nlh SlrMI. Room 1341.SaCtamenlO. CA 95814(Telel>hOne 916-<l45-1825)

PubhCllI,on. and InlormaHon Olloce660 se'CUI D''''e. SacramenlO. CA 95814-(1131CALIFORNIA GEOLOGYPutMlC InlOfmatlOr1· 916-445-5716

lo s A"9"Ie. 0l11Ce 107 Soulh Il<ollto'.vay. Room 1065.Los Angeles, CA 90012-4402(Telephone 213-620-3560)

Pleasanl HIli OUICe 380 C,v,e Dnve. Suite 100.Pleasanl H,II. CA 9<1523·1921

{Telep/'lON 415-646-5920}

CALIFORNIA GEOLOGY (lSSN 0026 (555) IS pubbJhed

monthly by the DeI'll'lment 01 Conse'''''I",n. D,v,s"," 01

Mines andGeology The Record. OUoce I' at 1721·2OthSlfeet, Sacramento. CA 9S814 Second class postagepaid at SacramenlO. CA Poslmasle" Sllnd add,.,.ChangelllQ CALIFORNIA GEOLOGY (USPS 35 0 840).

Sox 2980. S&cramenlo. CA 95812-2980

RGPOft. eonc.rn'ng Olvlloon 01 M,n.s and GeologyP'Ojects and arllCleS and newllllllm. '1I1atlld 10 lhe lIarthSCHIncGSlnCahlo'lIIa are Indu<led;nlhe magaz,"e. Con·lnbuled a,IICIe•. »hOlographs, news,tems, and geoIog;cslhIIIIIhng announce"'ll<lls It....... ICOfT1(I

THECONCLUSIONS ANDOPINIONS EXPRESSED INARTICLES ARE SOLelY THOSE OF THE AUTHORSAND ARE NOT NECESSARILY ENOORSED 8'1' THEDEPARTMENT OF CONSERVATION

AEG 33rdAnnual Meeting

The Aliegheny·Ohio Seclion of the

Association of Engineering GeoIogiS1S

(AEG) will hasl the 33rd Annual Meeling

of the Association of Engineering Geolo

9iSls on October 1-5. 1990 in Pittsburg.

Pennsylvania. The theme of this nalional

meeting is "Engineering Geology for lhe

9O·s." The program irlCludes technicalsessions. symposia, and short courses.

To receive a brochure and infonnation

for registralion and exhibits contact:

AEG. MEMS

P.O. Box 270Greensburg. PA 15601

(412) 836·6813, (800) 343-5129

or (800) 441-1674 (in PAl

CoastalConference

The 1welfth intemalionaJ conference titled"Our Coastal Experience: Assessing lhe

Past, Confronting the FUlUre" will be heldfrom October 21-24. 1990 in San Antonio.Texas. The conference is sponsored by the

CoaslaJ Society. Shoreline retreat ;s

occurring along 86% of California's 1.100

mile-long coast. An eslimated $100 millionin damage occurred to ocean fronl properly

in Cali fornia during 1983 storms. M·vance<! planning will help miligale future

losses. For additional information contact,

William Wise

Slate University of New York

Stony Brook. NY 11794

(516} 632-8656

COulI,pondance ,hllVld ba addtllsud tll Ed'lo'CALIFORNIAGEOLOGY. 660 llII,eut Or.ve. Sac:remenlo.CA 95814-0131

Subscnpllnns. $1000 pe ' yell'. S'ngle copies: $1.00Gect1 send S4JDSC"plit>l1 ord&rS and c ~ a n g e llt add'ess,nlOfmelron IIICALIfORNIA GEOlOGY. PO, Sox 2980,

SacrllfTlentll.CA 95812-2980.

AugUSl 199ONolume 43/Number 8

CGEOA 43 (8) 169·192 (1990)

The "ConfererlCe on Geologic Remote $ensing: Exploralion. Engineerin9 and the

Environmen1" will be held from April 29 to May 2. 1991 at the Marriot t City Center.

Denver. Colorado. The conference will include applications of remote sensing lechnoJogy directed tOVJard mineral and hydrocarbon (oil and gas) exploration. engineering

geology problems. and environmental applicalions. There will be over 200 technical

presentations by experts from more than 30 countries. During the past 10 years there

has been significanl application of remote sensing towards eat1h science. For additional

information contad:

Nancy J. Wallman. ERIMP.O. Box 8618Ann Arbor. MI48107

(313) 994-1200. Ext. 3234

'7 0 CALIFORNIA GEOLOGY AUGUST 1990



A Photo Essay

Sea Cliff Erosion:

A Major DilemmaBy

ROBEAT M. NOARIS,

Professor 01 Geology. EmentusUniversity of California. Santa Barbara

Photo 1. se a elill composed oltha Capistrano Formalion at San Clemente Stale

Beach. Orange CounlY. The Santa Fe Railway at the cliff base prolects this clilt

from direct manne allack. Nonmanne processes. chiefly rain wash. caused the

!Iutmg and badlands topography In this soft rock unit. Note the accumulation of

lalus al the cliff base. Photos by Robert M. Noms, except as noted.

INTRODUCTION

A her many years or observation. theauthor concludes that various engi-

neering structures used as protective

measures to reduce or eliminate sea cliff

erosion in California are not effective

over time. A great deal of time. money.

and dislress can be avoided if. prior 10

buikling structures at or near the top of

sea cliffs. an ample zone is allolted fornaturally occurring cliff erosion to lake

place. Because protective devkes con-

structed at the base of sea cliffs provide

only temporary protection. and in the

long term these partial protective meas-

ures always fail. alternatives should be

considered.

Geologists have long recognized that

all cliffs are inherently unstable. and are

only temporary features over geologic

time. Cliffs cut in hard crystalline rocks.like El Capitan in Yosemite Valley, are

more durable than cliffs cut in soft

sedimentary rocks. but both will yield

eventually 10 erosion. On the California

coaSI there are very few durable rock

outcrops: most coastal cliffs are cut in

relatively weak sedimentary rocks and

steep cliffs are eroded by wave action

which regularly undercuts the cliffs and

removes fallen debris from the cliff

00.. .

In places where the sea has retreatedfrom the cliff base for some years. talus

and loose soil and rock (colluvium)"

from the cliff lace gradually pile up at

the base of the cliff and build upward

toward the lop of the cliff. This proc-

ess is evident. for example. a t San CIe-

menle Stale Beach, Orange County

(PhOtO 1). Here, the Santa Fe Railroad

'SeII Glos.sary. page 177

track constructed along the base of the

cliff has protected the cliff for many

years Irom direct wave attack. In the

intervening years. Ihe pile 01 eroded

rock and soil accumulating at the cliff

base has reached nearly half way up the

original cliff al many places. As this

erosional process continues, the near,

verfical original cliff will be replaced

with a gentler slope near the angle of

repose· for dry material. Over a period

of time, even the top edge of the cliff

will wear back or retreat a considerable

distance.

SEA CLIFF RETREAT

Marine ErOSIon

Sea cliff retreal is caused by marine

and nonmarine agents, including wave

altack. solution, and wind driven salt

spray. The main type of marine ero-

sion is direct wave altack at the cliff

base. This process frequently quarries

out weak beds at the base of the cliff

and eventually undercuts the cliff to the

point where the overlying unsupported

material collapses onlo the beach.

Waves also work along joint or fault

planes 10 loosen blocks of rock or soil

(Photo 2).

The second type of marine erosion

that causes sea cliff retreat is known as

solution erosion. a chemical process in

which the soluble minerals are dissolved

out of rocks. The solution process is

effective on limestone cliffs where seawater dissolves the lime in the rocks.

resulting in the formation of deep

notches. This process is very important

on some raised coral islands in the

south Pacific Ocean and on the lime-

stone coasts of the Mediterranean and

the Adriatic seas. However. only minor

amounts of limestone occur along the

California coast and solution is not amajor cause of sea cliff retreat,

CAlIFORNIAGEOlOGY AUGUST 1990



Photo 2. Marine erosion of Monlerey Formation at Gaviota

State Beach. Santa Barbara County. Wave erosion has cut a

rock plalform at the base of the cliH and created a small sea

cave in a joint crack.

CALIFORNIA GEOlOGY

Photo 3. Erosion of sea cliff caused by waler from a leaking

drain below a concrete porch at a cliff-lOP house: photo taken

in1974.

... Photo 4. Same house (lefl) shown in Photo 3; photo taken

in 1980. Repair work to prevent erosion of the cliff included

installafion of a drain pipe (extreme left) to prevent water

from flowing over the cliff edge and a sea wall of wooden

piles constructed at the cliff base.

A third type of marine erosion occurs when winds pick up

salt spray from waves and drive the spray against sea cliffs.

This salty water may be absorbed by porous sedimentaryrocks. and as the water evaporates. sal! crystals form on the

soil and in the porous rocks. The surface of the cliff malerial

slowly flakes of f and falls 10 the beach below. This process

affects the enfire cliff face. unlike wave erosion and solution

erosion which occur only where sea water comes into direct

contact with the rocks of the cliff.

Barriers placed at the bottom of the cliff may defer wave

erosion, but may have no effect on saIl spray or on solution

processes.

AUGUST 1990



.... Photo 5. Same clill seen in Photos 3

and 4; photo taken in 1987. The sea

cliff has retreated back Irom the edge

01 the porch ollhe house (right side

01 photo). The drain has lallen oil: an

alcove is developing underneath one

building (second 'rom right).

Photo 6. Same cliff shown in

Photos 3-5; photo taken in 1989.

The alcove under the house on lhe

right has been enlarged.

Nonmarine Erosion

Nonmarine agents responsible for

cliff erosion include chemical and

mechanical erosion processes. surface

drainage water. and rainwater. Noneof these processes are affected by con

struction of cliff-base protective struc

tures. Moreover, it is a serious mistake

to ignore these processes when design

ing protective devices because they may

account for as much as half of the cliff

retreat along portions of the California

coast (Photos 3-6).

Erosion is generally a gradual proc

ess. Chemical erosion causes oxidationand hydration. These processes may

remove cementing materials in rocks,

allowing grains to separate from one

another. Volume changes by hydration

or oxidation can weaken or W€dge

rocks apart. Mechanical erosion proc>

esses. such as the freezing and thawing

action of water in crevices. are gener

ally not an important factor in Califor

nia due to the mild climate along the

coast.

Surface water runoff and wind-drivenrainwater are important sea cliff erosive

agents. Water running over the cliff

edge and wind-driven rain causes thefluting· often seen on cliff faces. These

'See G l o $ ~ r y . pag8 177.

same processes have sculptured bad

lands topography. such as Red Rock

Canyon in Kern County. Califomia and

Bryce Canyon in Utah. This type of

topography is developed on soft. rela

tively unconsolidated rocks like

mudstones or clayey shales (Photo 1).

Groundwater seeping from a cliff

face may cause another kind of non

marine erosion called spring sapping·.a process which creates alcove-like

reentrants on the cliff face. and undermines and weakens the strata above

(Photo 7). This process has excavated

large valleys on windward parts of theHawaiian Islands where very large

springs emerge from the porous lava

flows. Similar effects occur on the

bluffs of the Snake River near Twin

Falls. Idaho. However. persistent flowsof groundwaler and active spring sap

ping are minor on the generally arid

Califomia coast.

Where coastal developments are not

serviced by municipal sewage systems.

effluent from septic tanks may cause

spring sapping of a sea cliff. Evenwhere well-defined spring sapping does

not occur, the septic system effluent

will raise the pore pressure in sedi

ments or rocks Into which it is introduced. and thus reduce shear strength

CALIFORNIA GEOLOGY AUGUST 1990



Photo 8. Plastic sheeting has been hung over the sea cliff to

protect it from water draining over the cliff top, Isla Vista, Santa

Barbara County. Photo taken in 1986.

-

..... Photo 7. Same c\iU top shown in Photo 8.

CliU top beneath porches has retreated

and porch raillngs have been made more

secure. Concrete column and foundation

are exposed under the porches of the

houses.

..... Photo 9. Sea c1ilf at More Ranch Beach.

Santa Barbara County; photo taken in

1971. Water is seeping from a

permeable zone (dark area) about two·

thirds of the way up the clill. This water

causes spring sapping and sloughing of

the eli!! face. The water is probably

draining from septic tanks and garden

irrigation on the cliff top.

If bedding. fracture, or joint planes dipseaward, water may move along these

planes and rock slides may occur. In

stallation of sewer systems in developed

areas of the coastline can greatly reduce

cliff erosion caused by spring sapping.

Property owners can protect cliff-top

land from erosion by using drainage

systems to carry water away from un-

stable areas and to prevent surface runoff down the cli ff face. The cli ff top

can be stabilized by planting drought

tolerant vegetation, Vegetation that

requires regular watering will exacerbate

the problem it is meant to correct.

Even drought-resistant vegetation may

have undesirable effects because roots

wedge rocks apart during growth. It is

impractical to place plants on the edge

of vertical cliffs or on cliffs where the

retreat rate is so rapid vegetation cannot be established.

Plastic sheeting has also been used to

protect cliffs from rain wash (Photos 8

and 9). However, constant repair and

maintenance are required to keep the

plastic in place. Strong winds, espe

cially those occurring during storms,

can tear the sheeting and leave the cliff

face unprotected when most needed.

'"CALIFORNIA GEOLOGV AUGUST 1990



,

-Photo 11. Rotational slump. Santa

Barbara: photo taken in February 1978.

Several houses were destroyed by this

slide which occurred aher a lew weeks

01 heavy rainfalt. The head scarp IS

about 20 feet high. Marine erOSion

undercut the cliff. The slide was probably

triggered by penetration 01 rainwater imo

cracks and joints near the chI! edge.

"

. . Photo 10. Small translational rock slide

in the Monterey Formation, Hope Ranch

Beach, Santa Barbara County; photo

taken in 1984. This was a sudden

bedding·plane rock slide, a common

occurrence where the thin-bedded

MOnlerey Formation dips steeply

seaward.

..

--,.•

,.-. '.'" , , ~ - u ..

.,

••

Other Faclors

Landslides can occur in dry or wet

materials. Movement may be slow. or it

may be rapid if it occurs along a con·

cealed bedding plane structure. There-

fore. landslides may involve larger

blocks of me sea cliff than are affectedby weathering processes and may cause

dramatic property damage (Photos 10and 11).

People and animals also affect sea

cliff erosion. For example. foot trailsup steep cliffs result in increased ero

sion; burrowing gophers and other ani

mals can weaken soft rocks when the

burrows intersect cracks in dry soil.

Piping. the development of subterra

nean channels which are rapidly en

larged by water. may result.

MITIGATION

Prior to slope failure. property own-

ers often realize there is a problem and

seek an engineering solution. Becausean effective long-term solution is likely

to be very expensive. less expensive

protective measures. that only defer the

problem by slowing - not stopping

the cliff retreat and erosion. are taken.

These half-way measures include revet

ments constructed with large boulders

placed at the base of the cliff. gabions

(rock-filled baskets) stacked at the cliff

base. pil ing and other types of sea walls

(Photos 4-6). However. any barrier that

is not keyed into the bedrock at the cli ffbase and is not continuous to the cliff

top. wil l eventually fail to provide any

protection to buildings and structures at

the c li ff top. Even where the ent ire c li ff

face is protected with a continuous

sheet of concrete, if it is not massive

and keyed into the bedrock at the base

of the cUff. fai lure Vlill occur within a

few years (Photos 12-15).

State and local government agencies

involved in zoning and building safety

usually do not approve construction ofsea walls and other protective structures

because these structures occupy beach

space. are usually unsightly. require con

tinuing maintenance. and hinder beach

access. However. some type of protec

tion is usually authorized once the prop

eny owner is able to show building

damage is imminent.




SUMMARY

1lIere is no simple engineering s0 -

lution to save a diff-top building

threatened by erosion. Most remedial

measures that are affordable for an

individual property OIAIIler will only

reduce the rate or erosion. nol stop

it. In the long tenn. the same prob

lems will occur again and ultimately it

will be necessary to condemn anddemolish the structure because diff

erosion is part of the on-going ge0-

logical process. Geologic conditions

and common sense suggest that it

would be less costly for both prop

erty owners and taxpayers if a stripseveral hundred feet wide landward of

all cliff lOps was carefully managed.Photo 12. View 01 a cliff showing a porch projected out Irom a cliff-top house. Isla

Vista. Santa Barbara County. Photo was laken in 1971. Groul was sprayed onto the

cliH face to protect the cliff from wave erOSion. Pharo courtesy of Duke UnIVersity Press.

Photo 13. Same sea cliff and prOjectmg porch shown In Photo

12: photo taken in 1978. Wave erOSIon has atlacked the base

0' the grout covering. and drainage over the cliff edge has

eroded the upper ooges 01 the coaling. A covering at jute

sacking has been added at the cliff top (left of grout cover).

Photo courtesy of Duke Universiry Press.

Photo 14. Sea cliff and prOJectmg porch; photo taken tn 1980.

Only a remnanl of the concrete grout cover remains. held in place

by lhe porch support. The concrete covering reduced the tale 01

cliff relreat as shown by the slight seaward butge in the lower part

of the cliff. but il 'ailed 10 SlOP lhe erosion. Photo courtesy of

Duke University Press.

'"CALIFORNIA GEOLOGY AUGUST 1990



•

Photo 15. Same sea cIiH locatIOn shown In Photos 12-14; photo laken In 1987 In 1982, the portIon of the porch extending

oul Ollef the cli ff was removed. Continued erOSion has caused the di l lO relreal under the edge 01 the porch area. but some

seaward bulge In the eli'! is ShU evident.

REFERENCES

Griggs. Gary e., and savoy, laurel E., edl-

lors. 1985, l iving with the CaUforrwa

coast; Duke Umverslty Press, Dumam,

North Carolina. 393 p.

Noms. RObert M.• 1968. sea all retreatnear santa Barbara. California: Mineral

Information $ervk::e, v. 21. 00. 6 ,

p. 87-91,Noms. Robel1 M.. 1985. Southern ~ n l aBarbara County. Gaviola Beach 10 Rln·

con Point. Chapter 15 in Gnggs, G and

Savoy L. editors. LMng WIth the Cahlor-

rlla coast Duke UmVer5lry Press. Dur-

ham, North CarolIna. p. 250-278.

Pilkey. Omn H .. 1989, The engmeem'lg of

sand: Journal 01 Geological Education.

\/. 37. P 308-311

CAlIFOflNIA GEOlOOY

GLOSSARY

angle 01 repose "wumum a"lgle oj

slope al whICh loose malena! comes

to rest wllhoUl sliding,

colluvium: A loose mass 01 lalJen sot!

and redo; collected al the base01a

slope or chft.

l lutlng: A venteaJ channellormed by

d,HerenbaJ weathenrog and erOSIOn

on me lace 01 a el," or rock surface.sp"lng sapplng EroSlOl'l around a

seepage '" a ell" face, resulting In

retreat 01 the chff.

AUGUST 1990 1n



Lower Member Deposition,

HUNGRY VALLEY FORMATIONLos Angeles and Ventura Counties

By

ROBERT D. LOEFFLER, Geologist

JEFFREY D. BENNETI, GeologistGeological Audit Services

Yorba linda, California

Figure 1. Location map showing generalized geology 01 the study area including the

Hungry Valley Formation (modified trom Ramirez. 1984).

'.'.:'.

LEGEtlD

- FAULT L ~ E STT TfiRUsr FAULT LUIES

N

j

.0 0 • •0

..." ..

•

Based on Ridge Basin sedimentationrates. the top of the Hungry ValleyFormation is apparently 5.0 to 4.5mybp (Crowell. 1982a). although thetop of the formation could be as youngas 4.0 mybp (Ramirez. 1984).

feet above the base of the formation(Crowell 1950. 1982a; Ramirez.1984). Magnetostratigraphy. the technique of measuring remnant magneti

zation. was used to date the rocks that

contain the fossils. The fossils werefound to be between 5.5 to 5.0 millionyears before present (mybp) (Ensleyand Verosub. 1982).

RIDGE ROUTE AND

,. PEACE VALLEY FORMATlOtlS

"

.........GORUAN

TEJON PASS

HUNGRY VALLEYFORMATION

DRY CREEK

THRUST

llLOCK

Age

The Hungry Valley Formation isconsidered Pliocene age based on vertebrate fossils and the rocks that contain them. These fossils are called theKinsey Ranch fauna from the placewhere they were discovered and in-clude fragments of horses teeth. andbones of tapir. rhinoceroses. camels.and antelope. Kinsey Ranch fossilswere discovered approximately 600

depositional history of the lower member of the Hungry Valley Formation ispresented in this article.

The sedimentary history of thePliocene Hungry Valley Formation

chronicles the end of Ridge Basin development. the commencement ofmovement on the modern San An-

dreas fault. and the conclusion ofmovement along the San Gabriel fault.

The area of this formation is at thenorthern end of Ridge Basin. in thecentral Transverse Ranges, Los Angeles and Ventura counties. California(Figure L Photo I) . The Hungry Val-ley Formation is divided into threeunits; (1) a lower member. (2) an up

per member. and (3) a conglomeratemember (Crowell. 1982a).

The lower member representsstream deposited fill. The upper member and conglomerate member represent water deposited fill. All threemembers were deposited in Ridge Basin which formed at the splintered Pacific-North American plate margin(Crowell and Link, 1982). Only the

INTRODUCTION

Along strike-slip 'ault zones wherefault movement has stretched or pulled

apart an area. basins develop over geo

logic l ime inlo which sediments are

deposited. Investigating the sedimentary

history of such basins provides insight

into the tectonic activity and other geo

logical aspects altha region. Ridge Basin

is one such basin thaI tormed betweenthe San Gabriel and San Andreas faull

zones near their juncture at Frazier

Mountain in southern California. Thisbasin has a thick. although relatil lely nar

row, down-dropped wedge 01 sedimentary

rock. The deposit ional history of this ba

sin is recorded in i ts rocks. This art ic le

describes a member of one sedimentary

rock Unll, the Hungry Valley Formation,

wIthin Ridge Basin....editor.

'"CALIFORNIA GEOLOGY AUGUST 1990



Photo 1. Upper ponion of the lower member 01 the Hungry Valley Formation near thelower member-upper member contact. Photos by Christina L. H. Loeffler.

deformed by faulting, and was spreadand smeared along the Sandbergthrust and the San Andreas fault.

LOWER MEMBER LITHOLOGY

The lower member of the Hungry

Valley Formation is the youngest.thickest. and most laterally el<tensive ofthe three formation units. It consists

predominantly of sandstone units butalso contains conglomerate units andsiltstone units. Lithofacies are mappable sedimentary features that arebased on physical characteristics andreflect the conditions of rock origins.The lithofacies code scheme for the

lower member is shown in Table 1 andused in FIgure 2. This scheme aids in

distinguishing. describing, and inlerpreting the various rock types within

the lower member of the Hungry Val-ley Formation (Miall. 1977. 1978).Such code schemes are also used tomap lithologic characteristics to delineate patterns of deposition.

Sandstones

RegIonal Geology

The Hungry Valley Formation is

truncated on the north by the modem,active strand of the San Andreas fault(Crowell, 1950. 1982a. 1982b:Ramirez, 1983, 1984. 1987; FIgure

1). Rock types to the north of the for-mation and the San Andreas fault zoneinclude Paleozoic (?) marble. quartzite.and schist: the Cretaceous Tejon Lookout Granite; the Miocene NeenachVolcanics; and the Miocene undifferen

tiated sedimentary Oso Lake and OsoCanyon formations (Ramirez. 1984).

Gneiss·. migmatite", and quartz

monzonite" of probable Precambrianage are exposed along the westernblock of the San Gabriel fault zone andin the upthrown block of the Frazier

Mountain thrust {Crowell. 1982bJ. Inthis vicinity the western edge of theHungry Valley Formation overlaps theSan Gabriel fault and rests nonconformably· on the Precambrian base

ment rocks. and conformably on theViolin Breccia (Crowell. 1982b: FigureI) . The Violin Breccia is a Miocene

0.see Glossary. page 184

sedimentary u n i ~ which formed as

steep talus deposits; a result of uplih

along the San Gabriel fault zone(Crowell and Link. 1982).

To the east and south, the Hungry

Valley Formation conformably overliesthe Ridge Route and Peace Valley for-

mations (Crowell. 1982b; Figure 1).

The Ridge Route and Peace Valley for-

mations are interfingered nonmarinesedimentary units which were deposited in Ridge Basin during the Mio-

cene. The Ridge Route Formationconsists of sandstone and conglomerate beds which represent alluvial, flu-

vial. and shoreline deposits. The predominant rock types of the Peace Val-

ley Formation are lacustrine (or lakedeposited fill), siltstone, and mudstone

(Crowell and Link. 1982).

Pre-Tertiary quartz monzonite anddiorite of Liebre Mountain occur eastand northeast of the Hungry ValleyFormation (Figure 1). The northeastern portion of the Hungry Valley Formation locally rests nonconformablyon the quartz monzonite and diorite(Crowell, 1982b). Much of the formation in thIs area. however. has been

Lower member sandstone rocks aretypically tan to buff in color and rangefrom very thick-beds to massive units.Large-and small-scale trough crossbeds occur In solitary and nestedstrata. and are the most abundant sedimentary structures in the sandstones(labeled as Facies 5t in Table 1: Rgure2; Photo 2). Planar cross-bedding(Facies Sp) occurs in single sets and is

commonly capped by horizontal lami-nations (Facies Sh). Erosional scoursare common between sandstonesiltstone contacts (Facies Se).

The sandstone units are fine-grainedto very coarse-grained and contain fine

pebble- to small cobble-sized clasts.Fining and coarsening upwards sequences of grain sizes are common.

Compositionally. the sandstones arepredominantly lithic arkoses·.

Conglomerales

Lower member conglomerate bedstypically occur in massively beddedlenses·, stringers. or scour fills' (Facies

Gm: Figure 2: Photo 3). These bedsare commonly disorganized although apreferred orientatIon is found in some

CAUFORNlA GEOlOOY AUGUST 1990 ''''



TABLE 1. LITHOFACIES SCHEME FOR LOWER MEMBER SEDIMENTARY UNITS (From Mlall. 1977. 1976).

Facies

Code lithofacies Sedimentary Structures Interpretations

Gm, massive. malrlx supported gravel none debris flow deposits

Gm massive or crudely bedded hOrizontal bedding. imbrication' longitUdinal bars. lagdeposits sieve depoSits

GI gravel, stratified trough cross-beds minor channel fills

Gp gravel, stratified planar cross-beds tongue-shaped bars or deltaicgrowths from older bar remnants

SI sand, medium to very coarse. solitary or grouped trough cross·beds dunes (lower flow regime)may be pebbly

Sp sand, medium to very coarse, solitary or grouped planar cross·beds tongue·shaped, transverse bars,may be pebbly sand waves (lower flow regime)

S, sand, very fine to coarse ripple marks of aU types ripples (lower flow regime)

Sh sand, very line to very coarse hOrizontal lamination, parting or planar bed flow (lower andmay be pebbly streaming linealion upper flow regime)

SI sand, fine low angle «10 degrees) cross-beds scour fil ls, crevasse splays,antldunes'

S . erOSional scours With clasts crude cross-beds scour fills

S, sand, line to coarse, may be broad. shallow scours Including scour Iillpebbly cross-stratificatIon

Sse, Sne, sand analogous to Ss, Sh, Sp eolian depoSitsSp .

F! sand, Silt. mud line lamination. very small ripples overbank or waning t100ddeposits

F" silt. mud laminated to massive backswamp depoSits

F" m,d massive, with fresh water molluscs backswamp pond deposits

Fm mud, silt massive, deSSicatIon cracks overbank or drape deposits

F, silt. mud rootlets seat earth'

C coal, carbonaceous mud plants. mud films swamp deposits

p carbonate pedogenIC feature soil

-''.

"" :•", -

II

••')1 \,

Photo 2. Nested trough crOSS-bedding in

sandstone (Facies St) in the lower member

of Hungry Valley Formation,

'Se9 Glossary. page 184

units. Lens and stringer thicknesses

range from 1 inch to 1.5 feet thick.

Scour f il ls are typically 1 to 2 feet

thick and 5 to 7 feet wide. Planar

conglomerate cross-beds (Facies Gp;

Figure 2: Photo 3) are rare. Clasts in

the cross-beds show a preferred orien-

tation paral lel to the roreset· beds.

Cross-bed sets range from 5 feet to 7

feet In thickness. Foreset beds dip at

angles ranging from 10 degrees to 15

degrees.

180 CALIFORNIA GEOlOOV AUGUST 1990



•

'&:Ie Glossary, J;lage '84.

This facies sequence is similar to sand

flat deposition in the South Sas

katchewan River. Canada (Cant and

Walker, 1978), Lensoidal and thick

bedded. laterally continuous massive

siltstones (Facies Fm) commonly com

prise the upper portion of a fining

upwards sequence. The lensoidal beds

most likely represent channel aban·

donment while the thick-bedded laterally continuous beds are typical of

flood plain deposits (Cant 1978:

Collinson, 1986).

Features of Donjek-type deposition

include the lenses of conglomerate (Fa

cies Gml. common in channel lag de

posits' and conglomerate planar cross

bedding (Facies Gp) representing

tongue-shaped bar deposits (Table 1).

A typical facies sequence in Donjek

type river deposition is a lining up

wards sequence from Facies Gm. Gp

to St. Sp to Fm. FI. and Sf. Similar sequences are uncommon but do occur

in the lower member of the Hungry

Valley Formation (Figure 2).

An idealized schematic block dia

gram of bed forms and geomorphol

ogy of the lower member 01 the Hun

gry Valley Formation is depicted inFigure 3.

,

.-

:..... . . , ~ .

-.

. ~ • •-

• 0;. .... '. .,,

. ,-

• -4

-'~

:. - s..--,

'.

.-,..- ~ " : -

.-.-

,

Photo 3. Ma1nlt-supported conglomerate units occurring 10 lenses and scours

(FaCies Gm) in the lower member of the Hungry Valley Formation.

DEPOSITIONAL SETTING

The lower member of the Hungry

Valley Formation was deposited in a

river system with an interlacing net

work of several branching and reunit

ing channels. This type of river system

is characterized by moderate to high

sediment yield, moderate relief. and/or

seasonal discharge fluctuations (Mian,

1977).

From field evidence, the lower

member of the Hungry Valley Forma

tion was deposited in a river system

that contained characteristics of two

model river systems used universally by

sedimentary petrologists to classify

river deposilional patterns: (I ) the

"South Saskatchewan" system. and (2)

the "Donjek" system,

Characteristic depositional features

of the South Saskatchewan·type riversystem include the abundance of soli

tary and nested trough cross·beds

(Facies St). The trough cross-bedding

represents in-channel sinuous-crested

dune deposits. Planar cross-bedding

(Facies Sp) represents migrating sand

dunes. Several facies sequences showFacies St overlain by Facies Sp, and

Facies Sp is in turn overlain by FaciesSh (horizontal lamination: Figure 2).

So

"Gm

"Gm

Gm

50

So

"Fm

So

"So

Fm

51, 5p , GmFm

gr

Go

"Fm

Siltstones

Figure 2. Stratigraphic column representa

tive of the lower member 01 the Hungry

Valley Formation. Leller symbols to the

right of the column refer to l ithofacies

described in Table 1.

5p . Sh . Gp, am

Fm

Lower member medium to very

thick-bedded massive siltstones are

typically red-brown to gray or green_

The massive siltstones commonly oc

cur in large lenticular beds or are laterally continuous with little variation in

thickness (Facies Fm). These siltstones

commonly conclude a fining upwards

sequence. Typically, the siltstones con

tain 1096 to 4096 disseminated sand.

Compositionally, conglomerate clast

types are predominantly plutonic.

metamorphic. and volcanic rocks.Clast sizes generally range from very

fine pebbles to small cobbles with local

occurrences of large cobbles. Clast

roundness is typically subrounded to

rounded although subangular to angu

lar quartzite clasts are nOI uncommon.

Statistical analyses of conglomerate

clasts in the lower member of the Hun

gry Valley Formation are discussed in

the section titled MClasl Petrology and

Paleocurrent AnalysisM

below.

CALIFORNIA GEOlOGY AUGUST 1990

'"



. . FlQure 3, SChematiC block dIagram of

braided Stream bed forms and geo

morphology based on a South Sas·

katchewan-Donlek type depositIonal

model believed to be representattlle 01

the lower member01the Hungry Valley

FormatIOn. Arrows repfesent bed form

m'OratlOn directIOns. CCB _ cross

channel bars, LB • IlngUOld bars

(longue-shaped). SF • sand flats.

FP • flood plain

TABLE 2. CLAST ANALYSIS OF LOWER MEMBER CONGLOMERATE FROM THREESAMPLING RUNS.

Clast AbundanceClast Composition In Percentages

Sample 1 Sample 2 Sample 3

granite 11 11 I.quartz monzoMe I. • I.diorlle (Includes 13 12 5quanz dlorlle and

granodiorite)

pegmatIte (includes • 17graphIC granite)felsic gnetss

•5 3

augen gneiSS • " 7mylOnite • , 1

metavolcaniCS 3 1 ,quanzlte •• '3 I.marble 1 • •rhyoille • I. 1

daate (includes • 7 15rhyodaCIte)

"" • , 3andesIte • • •Siltstone 1 1 •

CLAST PETROlOGY ANDPALEOCURRENT ANALYSIS

Three clast counts of lower memberconglomerate clasls were made with

an average of 100 clasts in each

coon!. The analyses of these counts

indicate the conglomerate uni ts in the

k>wer member are composed of 33 %

to 48 % plulonic. rock clasts. 31% to

45% metamorphic rock clasts. 11% to

21% volcanic rock clasts. and 0% to

1% sedimentary rock clasts crable 2).

The dominant clast Iypes are quartzite

and grani te. Table 2 is included here

to Illustrate the wide diversity of clast

types In the lower member of Ihe Hun

gry Valley Formation.

Paleocurrent data were measured

from channel axes and f rom trough

and planar cross-beds. Analysis of

these dala indicate Ihe f low direction

was from a south-southwest direction.

ORIGIN OF THEHUNGRY VALLEY FORMATION

Lower Member

Clast roundness in Ihe lower mem

ber of Ihe Hungry Valley Formation

suggesls possible rSlNOrking of olderconglomerate unUs. The source area

for Ihese units was from a north-north

east source. indicating a south-soulh

west flow direction. The source area

for these conglomerate units is nowdisplaced by the San Andreas faull.

Angular to subangular shaped quartz-

Ite. marble. metamorphosed gabbro.

and anorthosite' claSIS ( Ramirez.

1984) suggest a probable short lTans

pori history.

The Uule San Bernardino Moun

tains are Ihe probable source along the

San Andreas fault of all four clast types

(Ramirez. 1983) The initial uplift re

lated 10 the formation of the modem

Strand of San Andreas fault occurred

during the deposition of the lower


tion (Ramirez. 1983. 1984), Ma}or

trandorm displacements in this region

occurred along the present strand of

the San Andreas fault beginning 5 mil

lion to 6 million years ago {Crowell.

1982cl. These conclusions suggest

that denudation of the uplifting block

and subsequent erosion may have con

lTibuted various clast types to the lower


tion (Rgure 4). Continued uplift and

right lateral offset terminated deposi

tion of the lower member of Ihe Hun

gry Valley Formation approximately

5.0 mybp.

". CALIFORNIA GEOlOGV AUGUST Ilil90



Cant, D. J" and Walker. R. G.. 1978. Flu

vial processes and lacles sequences In

the sandy braided South Saskatchewan

River, Canada: Sedimentology, v. 25,

p. 625-648.

Collinson, J. D., 1986, Alluvial sediments:

in H. G. Reading. editor. Sedimentary

environments and facies. second edition: Blackwell Scientific Publications.

Oxford. p. 20·62.

Crowell. J. C.. 1950. Geology 01 the Hun·

gry Valley area, southern Calilornia:

American ASSOCiation ot Petroleum Ge·

ologists Bulletin, v. 34, p. 1623·1646.

Crowell, J. C.. 1982a. Pliocene Hungry

Valley Formation. Ridge Basin, south

ern Calilornia: In J. C. Crowell and M.

H. Link, editors. GeologiC history of

Ridge Basin. southern California: Pa·

cific Section. Society or Economic Pale

onlologists and Mineralogists, Los An·

geles, p. 89·98.Crowell, J. C., 1982b. GeologiC map or

Ridge Basin, southern Cahrornia: Pa

cilic Section. Society or EconomiC Pale

ontologists and Mineralogists, 2 sheels.

scale 1:24,000.

Crowell, J. C., 1982c, The teclonlcs or

Ridge BaSin, southern California: InJ. C. Crowell and M. H. Link. editors.

Geologic history 01 Ridge Basin. south

ern California: Pacific Section. Society

o! EconomiC Paleontologists and Miner

alogists. Los Angeles. p. 89-98.

Crowell. J.C" and Link M. H., editors,

1982, Geologic history of Ridge Basin,southern Cahlornia: Pacific Section.

Society of Economic Paleontologists

and Mineralogists. Los Angeles. 304 p.

Ensley, R. A., and Verosub K L..1982,

Biostratigraphy and magnetostratigra·

phy of southern Ridge BaSin. central

Transverse Ranges. California: In J. C.

Crowell and M. H. Link, editors, Geo·

logic history of Ridge Basin, southern

Calitornia: Pacific Seclion, Sociely of

Economic Paleontologists and Miner·

aloglsts, Los Angeles. p. 89·98.

Miall, A.D., 1977, A review 01 the braided

river depositional environment: Earth

Sciences Reviews. v. 13. p. 1·62.

Miall, A. D., 1978, Lithofacies types and

verlical profile models in braided river

depoSits. a summary: in A. D. Mlall.

editor, Fluvial sedimentology: Canadian

Society of Petroleum Geologists. Mem

oir 5, p. 597-604.

,

Cant, D. J.. 1978, Bed torms and bar types

in the South Saskatchewan River: Jour,

nal ot Sedimentary Petrology, v. 48. p.

1321·1330.

REFERENCES

The Pliocene lower member of the

Hungry Valley Formation represents

river sediment fil l of Ridge Basin after

cessation of offset along the San Gab

riel fault. This South Saskatchewan

Donjek type of river system reworked

lower member conglomerate units lo

cated north-northeast of lhe San An-

dreas fault. The modern strand of the

San Andreas faul t formed pre- to syn

deposilionally with the lower memberof the Hungry Valley Formation. Uplift

during the formation of the San An·

dreas fault is indicated by the occur

rence of subangular to angular quartz

ite. meta-gabbro. anorthosite. and

marble clasts possibly originating from

the Little San Bernardino Mountains.

The change from fluvial to alluvial

deposition in the upper member of the

Hungry Valley Formation indicates

massive uplift and erosion of the

upthrown block and the coincident

truncation of the sediment load from

the north.

CONCLUSIONS

SAN ANDREAS

These interpretations were based on

petrographic comparisons of marble

and quartzite clasts in the upper mem-

ber with those from the Uttle San Ber

nardino Mountains (Ramirez. 1983.1984).

Figure 4. Regional block

diagram showing primary

source area and transport RIDGE BASIN GROUPmedium ror sediments or the

lower member or the Hungry Valley Formation during the Pliocene Epoch.

Diagram restores 135 miles 01 right·lateral ollset along the San Andreas fault.

Conglomerate Member

The conglomerate member is the

youngest member of the Hungry Valley

Formation. A possible source terrane

for unique olivine basalt clasts in the

conglomerate member of the Hungry

Valley Formation has also been identi

fied (Ramirez. 1983. 1984) as occur

r ing in the Santa Ana drainage (sug

gesting 110 miles of right-lateral offset

since deposition of this member).

Upper Member

Upper member deposition is char

acterized by alluvial sedimentation shed

from the unstable uplifted flanks of the

Little San Bernardino Mountains

(Ramirez. 1983.1984). The source terrane of the upper member of the Hun-

gry Valley Formation also occurs in the

l i l lIe San Bernardino Mountains and

the Morongo Valley area. suggesting

135 miles of right-lateral offset along

the San Andreas faul t since depositionof the upper member (Ramirez. 1983.1984. 1987).

LOWER MEMBERHUNGRY VALLEY

F O R M A T I O N ~ _ - l ' c

{continued ,I

CALIfORNIA GEOLOGY AUGUST 1990

'"



GLOSSARY

Ramirez, V. R., 1983, Hungry Valley

Formation: Evidence for 220 kilome

ters 01 post Miocene ollset on the

San Andreas lault: in O. W. Ander

son and M. J. Rymer, editors, Tec

100lcs and sedimentation along

laults of San Andreas system: Pa

aIlC SectIOn, SoCIety of EconomIC

PaleonlologlSts and MmeraJoglsts,

Los Angeles, p 33-44.

Ramirez, V. R., 1984, Geology of the

San Andreas faull at Tejon Pass,

CaMornla: Unpublished M. A Ihesis.

UmverSlly 01 Calilornia. Santa Bar

bara, 256 p.

Ramirez, V. R.. 1987, 100rodl.lC11On to

the geology of lhe San Andreas fault

at Telon Pass area, Cal ifornia; In M.

H Link. editor, Sedimentary faCIes,

tectoniC relations, and hydrocarbon

Significance in Ridge Basin, Calilor·

nla' Pacif ic Section, Society ot Eco

nomIC Paleontologists and Mineralo

gists. Los Angeles. p. 1-4

anortho.lte A plutOfllC rock With grealer

lhan go.,.-. plagioclase feldspar

antidune: A tranSient sand dune tormed

on a stream bed and travels up

stream; charactenzed by erosion on

the downstream Slope and dePOSitIOn

on the upstream slope,

foreset: Sediments dePOSited on a

steep and advan<:lng frontal slope

gneiss: A fchated rock lormed by reo

glonal melamorptusm,

Imbrication: Overlapping clasts. such

as hies on a rool or scales on a bud,

lag depo.lt . : Coarse-grained matenal

that ts left behind alter currents have

WInnowed or washed away the Itner

matenal

lans: sediment deposit resembling a

convex lens lhat IS IhlCk in the middle

and Ihlns at Ihe edges.

lithic arkose: An arltosa IS a feldspar·

rich sandstone composed 01 angular

to subangular grains that may be

poorly to moderately well sorted. and

15 commonly denved Irom Ihe diSInte

gration of graOite or granitic rocks. A

lithic arltose conlams appreciable

rock fragments; specilically. a sand

stone contalmng 10% to 50% hne

grained rock fragments. 25"4 to 90%

feldspar, and 0% 10 65% quartz.

quartzite. and chen

mlgmlltite: A compoStte rock composed

01 Jgl'l8OUs-appearlng rocks, Jgneoos

rocks, and/or metamorphic rock.

nonconformity: SedlmeOlary rock that

rests on older Igneous or metamor

phic rock

quartz monzonite: A plutol\lC rock Wllh

between 35% and 65% plag.oclase

I ~ s p a r and 20% to 60% quartz

.coyr till: A process of excavatIOn and

rer. Ing a channel with sediment

...t earth: A rock uM undertylng a coal

seam thaI supported the vegetation

from which lhe coal was formed Rep·

resents a paleosol (an old soil).

California Geology

Editor-In-Chief Retires

M ary Caroline Woods, long-time Editor-in-ehief of

CALIFORNIA GEOLOGY, retired on May 1. 1990,

Mary began her career with Ihe Division of Mines and

Geology (DMG) as a geologist at the Sacramento oUice in

March 1974. Her first job was 10 edit DMG bulletins,special reports. and CALIFORNIA GEOLOGY magaZine.

She became Editor-In-Chief of the magazine in 1976.

After she received he r geology degree from the Univer

sity of Texas. Austin. Mary was hired by a Texas oil com

pany 10 plot subsurface geologic data After taking some

time to raise three daughters. Mary continued her geologi

cal career in 1963 as a groundwater geologist with theU.S. Bureau of Reclamation unlil she accepted a geologist

position with the DMG.

She is a member o f t he Association of Engineering

Geologists. Geological Society of America. Association

of Earth Science Editors. National Association of GeologyTeachers. ASSOCiation of Women Geoscientists. and the

American Association of University Women,

Mary shared her knowledge and experu5e wilh the many

Division editors and editorial assistants she Irained through

the years. She has written many art icles for the magazine

and countless other articles have been enhanced by her

editorial skills Her characteristically hard-working, coone

oos manner. and wann smile have been inspirational

Mary Carolme Woods, editor, author, and geologist

Mary's future plans include travel to see the geology of the

world, Her many friends and colleagues wish her well

,.. C A U F O R N ~ G E O L O G Y AUGUST 1990



Survey of

California Geology Readers

T he intent of CALIFORNIA GEOLOGY is to inform and enlighten the citizens of Califomia aboutdiverse earth science subjects. Geologic material of educational and scientific value is presented

ina format that

isuseful for both novice and professional alike. This magazine

isalso a forum fordisseminating geologic information about California from investigations by professional earth scien

tists. To better serve our readership. the staff of CALIFORNIA GEOLOGY is conducting a survey.

Your valuable response to this questionnaire is requested to assist us in designing future issues. We

welcome your ideas.

When completed. cut along dashed line. fold into thirds. place In the prepaid envelope stapled in

the center of this issue. and mai l.

o Geologist/Earth Scientist 0 Teacher, K-7

o Non-technical Articles About GeologiC Subjects

o Landslide Hazards

o Mining Industry

o Historical Geology

o Mimng Hislory

o Volcanology

o PhySical Geology/Geomorphology

o GeophySICs! Minerals E ~ p l o r a t i o n

(C) Which 01 the following subjects are of greatest interestto you? (Select 3)

o Seismology/Earthquakes

o Teacher,a-12

o College/University

Sludenl

o Librarian

o High School Student

(A) Background

(B) Which features of CALIFORNIA GEOLOGY

areofgreatest Inlerest

toyou? (Select 3)

o Geolechnical Engineer

o Miner/Prospector

o Mining Engineer

o Interested Lay Person

o Other _

I

IIIIIIIIII

IIIIIIII1

1

III1

1

1

1,II

11

rl31°1

S1

o In-Depth Feature Articleso Mineralogy

o Shorter Articles o Paleontology

o Brief Reviews of New DMG Publications o Petroleum Geology

o Tflvial Quizzes

o Earth Science Teacher'S Page

o Notices of Conferences and Events

o Book Reviews

o Field Trip Guides

o SOil Science

oEngineering Geology

o Hydrology/Hydrogeology

o Mined Land ReclamatiOn/Environmental Engineering

o Articles about DMG Investigations o Prospecting For Gold And Other Minerals

o Other (specify) _ o Olher (specllyl _


'"



(O} What kinds of art ic les would you want more of?

2 _

3 __ _

(E) Do you have suggestions for how CALIFORNIA GEOLOGY can beller serve you? Are artIcles too technical? Should more articles

be written for interested lay persons? What subjects interesl you least?

Commenls: _

CALIFORNIA

GEOLOGYThe eont. science mogcu.ine lor

evet"fOOe in the GoIderl StoteColifornia has hvndreds offaSCinating geologic leotures

hoispnng$.

Foull$, coves.glociers, Fossil beds, gold deposits ,

Eve<)' issue brings geologiC odYlffilure.

Nome _

A d d , ~ _

C"' """ Zip__

'"CALIFORNIA GEOlOGY

Moke check payoble 10:

DIVISION OF MINES AND GEOLOGY

P!eose moil check ond order

fOrlTl in !he postage p<IId

en.."lope provoded.

'''"'''''''o 110 (1 year)- 120 ('2 )'eOf$)

PAYMENT REQUIRED

W1THOROER.

AUGUST 1990



BOOK REVIEWSBooks reviewed in this section are not available lor purchase from OMG.

GEOLOGY OF CALIFORNIA. Sec-

ond Edit ion. By Robert M. Norris

and Robert W. Webb. 1990. JohnWiley & Sons. Inc .. 1 Wiley Drive,

Somerset. NJ 08875-1272. 541 p ..

$43.95. hard cover.

This edition includes over 100 more

pages than the first editlon. an e x panded glossary. and mOTe photos and

illustrations. This widely used college

geology lext is designed for anyone

wishing to learn more about the geol-

ogy of California. No previous training

in earth science is needed to under

stand the concepts. The photos and

diagrams have been chosen to illus-

trate and instruct readers about geo-

logic features in this state.

Two introductory chapters familiar-

ize readers with basic geologic con-

cepts. The following chapters describe

the geology of each of California's 11

geomorphic provinces; the San An-

dreas fault and offshore geology are

discussed in two separate chapters.

Northeastward vIew of the pinnacle-like Sutler BUlles. Often called the "smallest

mountain range on Earth," the Bunes cover about 10 square miles and the highest

peak, South BUlle, IS 2,117 feet tall. The Buttes are plug domes With a core of

andesite porphyry, and an outer f1ng of intrusive rhyolite. Meanders 01 the

Sacramento River are in loreground. Photo by John Burnell.

Tufa pInnacles at the southwestern shoreline of the ancestral Searles lake. 55 miles

northeast of Mojave. Some pinnacles are 140 leet high and more than 500 teet In

diameter at the base. These pinnacles were tormed by a combinallon of spontaneous

precipitation of calcite near Iime·riCh springs and the Influence of lime'secrellng blue'

green algae that lived in the lake during the Pleistocene Epoch. Photo by RM. Norris.

Four appendices acquaint readers

with technical words and terms. common minerals and rocks in California.

geologic time. and geologic theories

that pertain to California.

The landscape of California is the

culmination of a remarkable series of

natural events that began hundreds of

millions of years ago. The same

changes that occurred throughout

geologic time are occurring today. al

beit at dif ferent rates than they have

in the past. Geologic processes that

appear to be unimpressively slow dur

ing our lifetimes olten produce dra

matic effects when viewed over millions of years. For example. slip on

the San Andreas fault averages about

2 inches per year but in a mil li on

years this length adds up to 32 miles.

Another example is the tectonic upl if t

of the Sierra Nevada. The Sierra Ne

vada block is being uplifted by about

0.04 inches per year. and over the

past 3 mil lion years it has been up

lifted by about 10.000 feet.

CALIFORNIA GEOLOOY AUGUST 1990'"



This photo shows an unusually well exposed syl'ldinalfold at

Rainbow Basin. San Bernardino County. For scale note the

geologIst walkmg on the hili top In upper nght 01 photo. These

rocks are among the best known and best displayed sequence

of non·manne Miocene strata In the MOlave Desert. More than

3.000 feet 01 lake. stream, and attuvlal fan sedIments that

formed 10,000.000 to 30,000,000 years ago are exposed in thIS

area located eight mites northwest of Barstow. Many 01 these

sedimentary units are colorful, a result 01 the mineral content In

the rocks. Some rock units in thiS area were mined for borateand strontium minerals. Because of the well·displayed structural

geology in th is area, il is a popular training area for geology

students.

These beds also contain rich fossil evidence of long-extinct

mammals and give insight into the paleoenvironmental

conditions that prevailed In this part 01 California during the

Miocene Epoch. Recovered fossilized remains include severat

species of early horses, two kinds oj camels. mastodon.

chahcotheres (mammals relaled to rhmos). pronghorn

antelope, peccaries. dogs, and various forms of cats such as

saber·tOOlhed cats. One of the strangest fossIls found here IS

the huge bear-dog, a gnzzly·bear-bke beast that had an 11-

loot·long stnde. Fossil evidence IndIcates thIS area had a

climate that was similar to that 01 northern MexICO today WIthsummer (alns. In recogmtlOn 01 rts umque geologIC Importance.

Rambow BaSIn IS a Registered Nabonal landmar1t; lossll

collecllng IS prOhltlited. Photo by R. IrA Noms.

Wave'cut bench in steeply-dipping shale of the Miocene age

Monterey Formation, near Gaviota. Santa Barbara County. For

scale note man standing on bench in upper middle 01 photo.

Photo by R.M. Norris.

These examples illustrate that some

geologic phenomena are difficult to

appreciate because o f their immense

and inconspicuous significance t o o ur

daily lives.

During th e 1960s evidenc.e collected

from the east Pacific sea floor of f the

western coast o f N or th America gavescientists supporting data f o r A lf re d

Wegener's 1910 theory o f continental

drifl. In addition to the confirmation

o f continental drift. since th e 1960s

scientists have discovered paleomag

netism. sea-floor spreading, exotic and

suspect terranes, and polar wandering.

These important concepts have had

far reaching effects about ho w we

understand the geology of California

and ho w this region has evolved

through geologic time. Improved in

vestigative procedures enable earth sci

entists to comprehend previously pUZ-zling aspects o f California's geology.

(continued), , ,

". CALIFORNIA GEOLOGY AUGUST t990



Book Reviews (continued)

, - - - - - - - - - - - - - - - - - - - - - - - - - - -MAIL ORDER FORM

1.003.00

'.00

510,00

518.00

. . .• S20.oo

._-. . . . . S10.00

520.00

. .• S 1.00

. . . . . . S. . . 5. . . S

. . . . . . S20.oo

Price includes

poslage ond !oles tox

. . . . . . • • . . . S 7.00

....... 510.00

Rock Hounding

GEM TRAILS OF CALIFORNIA.Third edition. By James R. Mitchell.1986. Available from: Gem GuidesBook Company, 3677 San GabrielRiver Parkway. Pico Rivera. CA,

90660. 159 p. $5.95. soft cover.

Rockhounds will find directions to93 collecting areas in California.Jade. serpentine. rhodonite. jasper.agate. mariposite. petrified wood,quartz crystals. opals. chalcedony.and psllomelane are among the min·erals that can be found at the collecting sites. The sites are arranged geographically and each is accompaniedby a map: most site descriptions havean accompanying photo.

Indicote number of cople!

•BULLETINS

__ 8189 Mlnerols of Col,fornlo. 1966 .• . • . . .__ B190G.ology of northern Coliforn'o.1966

Complele oddrfll.s form on nU l page

SPECIAL REPOIHS

__ SR093 Eorly PI,o<:eneledimenlary hl!tory of .he Los Angeles Bosin,

Lo. Angeles ond Oronge counlles.1967 . . . . • . . • . . . . . . • . . . • S 1.25

__ 5R101 Geology of the Elysion Park.Repello H,lls oreo, Lo! Angele! County. 1970 . 5 2.50

__ SR118 Son Andreos foult In southern Colifornoo. 1975. 1:750,000 Kole . • . . . • . . • • • . . 5 4.50

__ SR143 Pori 5 Mlnerollond c1osslficolion of lhe greoter Los Angeles oreo, clossificollon

of sand ond grovel re.ource orfICIs. 50ugu!-Newholl production·conwmption r&glon ond Polmdole production·conlUf'l'lptlon region.

1987 (new) . . . • . . . . . . • . . • . . . . . • • . . • • . . • . . . . . . . . • • . S 8.00

__ SR146 Pori 2 Minerol lond c1oSSlfieollon: oggregole rnoteriols In lhe south

Son Fronc.Ko Bay oreO 1988 (new] . . . . . . . . • . . • . . . . . • . . . • • . .

__ SR146 Port 3 Minerollond clos.ifiColion: oggregote molerlols in the norlh

Son Froncisco·Monterey Boy oreo. 1988 (newl__ SR156 Minerollond c101llficolion of portlond cemenl concrele-grode oggregote

in the Socromento-Foirfield prodUclion·conwmphon region. 1987 (new)__ SR163 Surfoce ond groundwoter monagementln surfoce mined-lof\d redomotion.

1989 (new) . . . . . . . • . . • • • . . • .

SPECIAL PUBLICATIONS

__SP033Minerols ond roc:ks. 1962 . . . . . • .. •

. .

__ SP092 CALIFORNIA CEOlOGY mogoz.ine index 1948·1986. 1987 ._

__ SP093M,nes ond mlnerol produce" octive in Colifornio during 1986.1987

CALIFORNIA GEOLOGY__ 1yeor (12 isollfl')

__ 2 yeorsl24 IUlIfI') . • . .

__ Bock ;s!ues (Specify volume ond month] Indiv,duot,swes 51.00 eoch .

This is a personal account by Everett C. Olson. a paleobiologist emeritusat Ihe University of California. LosAngeles. "Ole. W as he is known to hisfriends. spent many years investigatingthe evolution of lower vertebrates fromthe Permo-Carboniferous. the origin of

mammals. taphonomy (the branch ofpaleoecology concerned with burialprocesses that occur after the death ofan organism). biogeography. and evolution of fossil communities. Reflections of his investigations are included.Over the span of his career. Olestrengthened ties between paleontolo'gists of the United States and theUnion of Soviet Socialist Republic.This book provides antidotes and in

sights into the career of a respectedpaleobiologist.

IIII

IIIIIII TOTAL AMOUNT ENCLOSED . .

I PAYMENT MUST BE INCLUDfOWlTH ORDERL

THE OTHER SIDE OF THEMEDAL: A Paleobiologist Reflects onthe Art and Serendipity of Science.1990. By Everell C. Olson. Availablefrom: McDonald & Woodward Publishing Company. P.O. Box 10308.Blacksburg. VA 24062-0308. 182 p.$22.95. hard cover.

Paleontology

Remote sensing, seismic diffractionand reflection, atomic absorptlon spectrometry, electron microscopy, electron diffraction analysis. thermoluminescent dating. thermography. andmass spectroscopy are Just a few ofthe varied and intricate techniques

used to illuminate once enigmatic geologic problems.

One on-going investigative aspectof California geology concerns extensional faulting. For many years flatlying faults have been recognized inthe eastern Mojave Desert. Basin andRange. and Colorado Desert of California. These faults were long interpreted to be thrust faults that had developed as a result of crustal shortening or compression. Although someof these faults are still believed to havebeen caused by this mechanism. evidence from recent investigations indicate that many of these flat-lying faultswere caused by crustal extension andthey merge at depth to form what iscalled a "detachment zone." Moreover. these "detachment faults" ruptured or broke at the more brittle crustal surface but become more elastic atdepth and respond to regional tectonicforces by stretching and thinning alongthe deep·seated detachment zone.

A folded. full-color geologic map ofCalifornia at a scale of 1:2.500,000 is

included with the book. This map depicts the regional exposures of rocktypes and their ages throughout thestate. For example, granitic rocks ofMesozoic age are delineated adjacentto Paleozoic sedimentary and volcanicage rocks. Geomorphic provinces areshown along with major faults. rivers.and lakes.


'"



· .. more Book Reviews

PAYMENT MUST BE INCLUDED WITH ORDER

ADDRESS _

NAME _

ADDRESS FORM FOR ALL ORDERS 1f-LPlease pnnl or lype V

into three categories; (I ) past and fu

ture development of the seismological

observatory. (2) crustal tectonic move·

ment and the distribution of earth

quake foci. and (3) analysis and inter

pretation of observatory data.

In addit ion 10 providing an historical

document of the seismographic sta-tions' first 100 years. this volume

serves as a compendium of current

observatory practice and offers a

glimpse into the future of seismology.

SollOfan DeSert Geology

GEOLOGIC EXCURSIONS

THROUGH THE SONORAN DES·ERT REGION. ARIZONA AND SON·

ORA. Arizona Geological Survey

Special Paper 7. 1990. Edited by

George E. Gehrels and Jon E.

Spencer. Available from: Arizona

Geological Survey. 845 N. Park

Ave .. 11100. Tucson. AZ 85719.

202 p. $22.25 (includes shipping

and handling charges) soft cover.

Make check or money order payable

to: Arizona Geological Survey.

Litehiser. 1989. Available from: Uni

versity of California Press. Berkeley.

CA 94720. 379 p. $48.00. hard

cover.

This book commemorates the

100th anniversary of the seismO"-

graphic stations at the University ofCalifornia at Berkeley. the oldest con

tinuously operating stations in the

Western Hemisphere. A distinguished

group of fellows, staff. and friends of

the stations met on the Berkeley cam

pus in May 1987 lo r a symposium

honoring the occasion.

Twenty scholarly papers presented

at the symposium are gathered in this

book. which covers subjects of past.

present. and luture seismological inter

est. The papers within this volume fall

For each site the author provides

informatlon on mineral and fossil va

rieties. site conditions. road conditions.

and land status. A few col lect ing sites

are privately owned and require en

trance fees. The author cautions that

land status can change. Therefore

each site should be checked locally belore visit ing to make sure collectors

are still welcome. This information can

be obta ined at a local rock shop or the

County Recorder's office

Seismograph StaMns

OBSERVATORY SEISMOLOGY.

An Anniversary Symposium on the

Occasion of the Centennial of the Uni-

versity of California at Berkeley Seis

mographic Stations. Edited by J.

CALIFORNIA GEOLOGY SUBSCRIPTIONS

TOTAL AMOUNT ENCLOSED: .$ _

- - - - - - - ~

CAUFORNIA GEOLOGV r ~ only j,lIln Inlormat>On Ifom your......-.g '-beI« allael! a t.oelffom a pnl In .. .

Geologic guides for 16 field trips

conducted in association of the 861h

annual meeting of the Cordilleran

Section of the Geological Society ofAmerica (held in Tucson. Arizona

dur ing March 1990) are included in

this book. Recent geologic investiga

tions confirm that extensional tec

tonic movement occurred in the

Sonoran Desert during the geologic

past. Although some faults in this

region are still believed to be true

thrust faults. evidence of crustal ex

tension accounts for many of the

high-angle range-front faults and

some low-angle flat-lying faults. High-

angle normal faults that are curved

and f latten at depth are termed l istr icfaults. These faults also merge at

depth to form a detachment zone. In

such areas the crust above this zone

behaves independently from the crust

below. In an extensional regimen. the

upper crust can rupture in a britt le

manner in response to crustal

stretching while the underlying crust

can respond to crustal stretching by

thinning.

(IndiVidual issues are 51.00 each)

EXPIA. DATE ACCT • _

o 2 yr. 520.00o 1 yr. 510.00

1.0. ' _

Your order subscrlpllon cannOl be processed unless COrr\K:1 amounl IS rem'lled All Foreign and

Canadian Ofders muSI be paid Wilt! an Inlemotlonal Money o.der or Drall payable In Unlled Slales

lundS Address ali orders 10 DIVISION OF MINES AND GEOLOGY. PO Box 2960. Sacramento.

Cailler",a 95812·2960

o NEW SUBSCRIPTION: Allow 60 days 10f delivery 01 lirsllssue.

o RENEWAL: To receive your magazine continuously. send In renewal 60 days beloreeXpiratIon dale shown on youraddress label. (Example: EXP9012 meansthat the subscnptlon expires on receipt of Decembef 1990 Issue.) Pleaseenclose address label Irom past Issue.

CITY _

STATE ZIP _

o GIFT: (Gift card from _

o ADDRESS CHANGE: Send us an old address label and yoUf new address.

Allow 60 days lor address change.

""

CALIFORNIAGEOLOGY AUGUST 1990



A Page for Teachers

Resources for Earth Science Teachers

Professional organizations that distribute materials aboutgeology and related subjects for classroom use are in-

cluded in this list. The information that is available, such as

catalogs, publication lists, teacher packets. books, and journals, is described under each organizational listing. Whenrequesting free materials, use school stationery.

AMERICAN ASSOCIATION OF PETROLEUM GEOLOGISTS. P.O. Box 979. Tulsa. OK 74101. (918) 584-2555.Geological Highway Mops. illuSlrated multicolored maps for

major highways in each region of the United States; information printed on both sides of map. $5.00 each plus$1.75 shipping and handling. A Manual for Technical

Presentations, a full-color guide to the preparation anduse of 35mm slides for effective presentations. $5.00.

AMERICAN GEOPHYSICAL UNION. Attention; Circulation Department, 2000 Florida Avenue NW. Washington,D.C. 20009. Geodesy, Geophysics, Oceanography. careerbooklets. free. The Earth In Space. journal. 9 issues peryear (September-May). $10.00 per year. Scientific Event

Alerr Network (SEAN) Bulletin. a source of informationconcerning meteoric. seismic, and volcanic activity worldwkie (monthly). $18.00 per year.

AMERICAN INSTITUTE OF PROFESSIONAL GEOLOGISTS, 7828 Vance Drive, Suite 103. AlVada. CO 80003.

(3031431-0831. Ground Water: Issues and Answers. apamphlet on topics concerning ground water. $3.50 each(50 copies or more. $2.25 each). Similar pamphlets arealso available for radioactive waste and hazardous waste.

FEDERAL EMERGENCY MANAGEMENT AGENCY(FEMA). Earthquake Program. 500 C Street SW, Washington. D.C. 20472. Earthquakes: A Teacher's Package for

K-6. developed by the National Science Teachers Association (NSTA) with grant from FEMA. This six-unit book is acomplete earthquake curriculum containing activities. lessonplans. line master. and background information. One freecopy per school while supplies lasl. Additional copies maybe purchased from NSTA (see address below).

GEOLOGICAL SOCIETY OF AMERICA (GSA), 3300Penrose Place. P.O. Box 9140. Boulder. CO 80301. (303)447-2020; (800)472-1988. Geological Publications Catalog. free. Future Employment Opportunities In the Geo·logical Sclellces. free pamphlet. The Earth Has A History,

a 20-minute program on geologic time. The concept ofgeologic time is explained by "walking the viewer throughtime" in the Rocky Mountain Front Range near Boulder.Colorado. VHS cassette. $25.00: 16mm film. $200.00.

NATIONAL ASSOCIATION OF GEOLOGY TEACHERS(NAGn. P.O. Box 368. Lawrence. KS 66044, (913) 8431234. NAGT sponsors regional meetings with field tripsand workshops. The annual meeting is held in conjunctionwith the Geological Society of America annual meeting.NAGT membership. $20.00. Journal of GeologicalEducation. source of information, ideas. and reviews for

high school and and college teachers: five issues per yearwith membership. ActivllY Source Book For Earth&iellce, $7.99 to members.

NATIONAL EARTH SCIENCE TEACHERS ASSOCIATION (NESTA). Publications/Sales; Art Weinle. 733 Lo-

raine, Grosse Point. MI48230-1235. (313) 882-2569.NESTA meets in conjunction with the National ScienceTeachers Association (NSTA). National meeting includesworkshops. Share-A-Thon. and Rock Raffle. NESTA mem

bership is $10.00. includes quarterly newsletter. Slide Sets.wide variety of subjects for upper elementary through introductory college levels: free brochure. Nesta Computer Pro

gram. Coordinator: Dee E. Drake. Huron High School.Ann Arbor. Ml 48104. (313) 665-7964. Public domainsoftware, 3 disks containing 5 to 6 programs each. with

tutorial and demonstration. Single disk. $2.00 plus $1.00shipping and handling: 3 disks. $7.00.

NATIONAL SCIENCE TEACHERS ASSOCIATION(NSTA). 1742 Connecticut Avenue NW. Washington. D.C.20009. (202) 328-5800. NSTA sponsors regional and na·tional conventions and produces a wide variety of publications. Membership is $35.00 per year: includes subscription

to &/ence and Children. designed for the elementaryschool teacher. Science Scope. designed for the middleschool/junior high schoolteacher. is $15.00 per year. Supplement to &ience Education Suppliers. an annual list of

suppliers' names. addresses. and telephone numbers for

materials in all sciences: free to members.

NATURESCOPE, National Wildlife Federation. 140016th Street NW, Washington. D.C. 20036. Digging fnto

DIllosaurs, Geology-The Active Earth. AstronomyAdventures, and Wild About Weather. a series of activitygUides dealing with natural science topics. Materials includebackground information. activities. master worksheets to du-

plicate for students. and additional sources of information.

Write for free brochure.

U.S. Geological Survey. Geological Inquiries Group.907 National Center, Reston. VA 22092. (702) 648-4383.Teacher Packet of Geological Materials. pamphlets andinformation sheets. and how to order topographic. geologic. and special interest maps. Free; send request onschool stationery and specify grade level.. ..Compiled by

American Geologico/Institute. National Center for Earlh&ience Education. 4220 King Street, Alexandria, VA

22302. (703) 379·2480; (800) 336·4 746.

CAUFOANIA GEOLOGY AUGUST 1990 ,g ,



SlAte Of CAlifORNIA

lHE RESOURCES AGENCY

DEPAR1MENl Of CONSERVAliON

CAliFORNIA GEOLOGY

DIVISION OF

MINES AND GEOlOGYPOBOX 2980

SACRAMENlO, CALIFORNIA 9.5812·0131

USPS 3S0 840

AOORESS COUEcnON REOUEStED

... l:

Dr. Adolf Pabst. an expert on rare minerals and a professor emeritus at the University of California in

Berkeley. died April 3. 1990 in Berkeley. He was 90. Professor Pabst was a graduate of the University of Illinois andreceived his doctorate from the University of California,Berkeley in 1928. He joined the facuhy at V.C. Berkeleyupon graduation and taught mineralogy there for 40 years.

Thousands of students were first exposed to the mysteriesof mineralogy and crystallography in Pabst's laboratory inthe basement of Bacon Hall on ihe V.C. Berkeley campus.They will always remember the professor's painstaking concern that every detail in his lectures be exactly understood.

Dr. Pabst gave meticulous descriptions of even the most ordinary properties of minerals and crystal systems. To hisstudents. Adolf Pabst epitomized the dedicated Mold school"

teaching method of rigorously and precisely applying thescientific method.

Pabst's work was recognized internationally and he wasfrequently invited to universities throughout the UnitedStates and Europe as a guest speaker. He was a member of

numerous professional and honorary mineralogical societiesand held office in many of the organizations. [n 1965 he

received the Roebling Medal awarded by the MineralogicalSociety of America in recognition of his meritorious contributions to the science of mineralogy. This internationallyrecognized award is the most prestigious tribute given toAmerican mineralogists.

In acknowledgment of his work. the mineral pabstite wasfirst described and named for him in 1965. Pabslite-a bar

ium tin titanium silicate-was discovered in Santa CruzCounty and is the tin analogue of benitoite. California'sofficial gemstone. After retiring from the University in 1967.Pabst continued lecturing and conducting mineralogy andx-ray crystallography research there as professor emeritus.

In 1974 he was awarded the distinguished Friedrich BeckeMedal by the Austrian Mineralogical Society. Pabst's scientific publications include more than 90 papers and manyarticles.

SECOND ClASS POSTAGE PAIDAT SACRAMENTO, CAltfORNIA

MEMORIAL

Adolf Pabst. 1899-1990

Photo courtesy of V.C. Berkeley.

Date post:	08-Apr-2018
Category:	Documents
Upload:	bornite
View:	227 times
Download:	0 times

California Geology Magazine August 1990

Documents