Stratigraphy of the 

Southern Coast Ranges near the 

San Andreas Fault from 

Cholame to Maricopa, California

GEOLOGICAL SURVEY PROFESSIONAL PAPER 764
Stratigraphy of the 

Southern Coast Ranges near the 

San Andreas Fault from 

Gholame to Maricopa, California

By T. W. DIBBLEE, JR.

GEOLOGICAL SURVEY PROFESSIONAL PAPER 764

A discussion of the regional stratigraphy of the McLure Valley 

area, Temblor Range, Carrizo Plain, Cuyama Valley, Caliente 

Range, La Panza Range, and Sierra Madre Mountains

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1973
UNITED STATES DEPARTMENT OF THE INTERIOR 

ROGERS C. B. MORTON, Secretary

GEOLOGICAL SURVEY

V. E. McKelvey, Director

Library of Congress catalog-card No. 72-600327

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 

Price: Paper cover-80 cents, domestic postpaid; 55 cents, GPO Bookstore. Stock No. 2401-00300
CONTENTS

Abstract _ _ __________________________

Introduction _____________________________________

Scope and purpose ___________________________

Problems of stratigraphic terminology _________

Chronology used _____________________________

Tectonic areas ____________________________

Crystalline plutonic and metamorphic rocks ________

Eugeosynclinal sedimentary and igneous rocks _____

Definition ___________________________________

Franciscan rocks ____________________________

Ultramafic rocks _ __ __________________

Jurassic (?) and Cretaceous marine sedimentary sequence __ ______________________________

Definition _____________________________

Gravelly Flat Formation _____________________

Hex Claystone _______________________________

Panoche Formation __________________________

Upper Cretaceous and lower Tertiary marine sedimentary sequence _________________ 

Definition ___i_______________________________

Marine clastic sedimentary rocks ______________

Lower Tertiary marine sedimentary sequence _______

Definition ________________________ 

Lodo(?) Formation __________________________

Avenal Sandstone ____________________________

Kreyenhagen Shale __________________________

Point of Rocks Sandstone _________________

Wagonwheel Formation ______________________

Middle Tertiary sedimentary sequence _____________

Definition ___________________________________

Simmler Formation __________________________

Vaqueros and Temblor Formations ____________

Review of nomenclature __________________

Vaqueros Formation ____________

Quail Canyon Sandstone Member __ 

Soda Lake Shale Member _____________

Painted Rock Sandstone Member 

Temblor Formation ______________________

Cymric Shale Member ___________

Wygal Sandstone Member ____________

Santos Shale and Agua Sandstone Members __________

Carneros Sandstone Member ________

Media Shale Member _________________

Page

1

1

1

3

3

5

5

6

6

6

6

6

6

7

8

8

9

9

9

10

10

10

10

12

13

13

13

13

14

15

15

17

17

17

18

18

20

20

22

23

23

Page

Middle Tertiary sedimentary sequence Continued 

Vaqueros and Temblor Formations Continued 

Temblor Formation Continued

Buttonbed Sandstone Member ______ 23

Monterey Shale ____________________ 24

Review of nomenclature _____ _ 24

Stratigraphic units southwest of the San

Andreas fault 24 

Saltos Shale Member ______________ 25

Whiterock Bluff Shale Member ____ 26 

Stratigraphic units northeast of the San

Andreas fault. 27 

Gould Shale Member __ 28 

Devilwater Shale Member 29 

Interbedded shale and sandstone member ____________ 29 

McLure Shale Member __ 29 

Belridge Diatomite Member 30 

Branch Canyon Sandstone ___ 30 

Santa Margarita Formation ___ 31 

Caliente Formation 31 

Basalt _________________-___ 32 

Bitterwater Creek Shale _____ 33 

Reef Ridge Shale ___________ 33

Upper Tertiary sedimentary sequence 33

Definition _____ 33

Deposits in the San Joaquin Valley area 34

Terminology __ 34

Etchegoin Formation 36

San Joaquin Formation 37

Deposits in the Salinas Valley-Cuyama Valley

area _____ 37

Unnamed marine sediments _ 37

Quatal Formation 38

Morales Formation 38

Valley deposits 39

Definition ________ 39

Paso Robles Formation 39 

Tulare Formation _ 40 

Surficial deposits 41 

Relationship of sedimentary sequences to the San

Andreas fault _ _ 41 

References cited _ '- 42

ILLUSTRATIONS

FIGURE 1. Index map of part of central California showing area studied __________________________________

2. Generalized geologic map showing distribution of major stratigraphic sequences in the southern Coast 

Ranges near the San Andreas fault from Cholame and Avenal to Cuyama and Maricopa 

Page 

1

III
IV CONTENTS

Page 

FIGURES 3-8. Stratigraphic diagrams showing:

3. Major Mesozoic and Cenozoic sedimentary sequences of the southern Coast Ranges near the

San Andreas fault from Cholame and Avenal to Cuyama and Maricopa 3

4. Cretaceous and Cenozoic chronology of the southern Coast Ranges 4

5. Jurassic (?) and Cretaceous marine sedimentary sequence in the southeastern part of the

Diablo Range and in the Temblor Range 7

6. Lower Tertiary marine sedimentary sequence in part of the Diablo Range between McLure and

Cholame Valleys and in the Temblor Range 11

7. Lithologic units of the middle Tertiary sedimentary sequence southwest of the San Andreas

fault from Cholame to Cuyama _ _ 14

8. Lithologic units of the middle Tertiary sedimentary sequence northeast of the San Andreas

fault from Avenal to Maricopa 15 

9. Map of the Temblor Range showing geographic localities mentioned and areal extent of the Tertiary

formations _ __________________ 19

10. Geologic map of the Chico Martinez Creek area, Temblor Range, showing members of the Temblor

Formation and Monterey Shale ________ 21

11. Stratigraphic diagram showing sections of the Temblor Formation from Cedar Creek to Zemorra Creek

in the Temblor Range ____________ -_ _ - 22

12. Map showing probable original and present areal extent of contemporaneous formations or facies of

mainly middle and late Miocene age in southern Coast Ranges ___ _ _ 25

13. Diagram showing classification and names applied to the upper Tertiary (Pliocene) sedimentary sequence in southeastern part of the Diablo Range and Kettleman Hills 35

14. Stratigraphic diagram showing valley deposits and upper Tertiary sedimentary sequence of the San 

Joaquin Valley area along east side of the southeastern part of the Diablo Range, Kettleman Hills, 

and the Temblor Range ___________ _______________________ _ __-_ 36

TABLES

TABLE 1. Names applied by other investigators to strata herein assigned to the Vaqueros and Temblor Formations of map region of figure 2 _________ 

2. Local Stratigraphic units of the Temblor Formation in the Temblor Range between Chico Martinez 

Creek and Bitterwater Creek _______ ____________ _ 

3. Members of the Temblor Formation exposed at Devils Den ___________ _____ _ 

Page

16

20

24
STRATIGRAPHY OF THE SOUTHERN COAST RANGES

NEAR THE SAN ANDREAS FAULT 

FROM CHOLAME TO MARICOPA, CALIFORNIA

By T. W. DIBBLEE, JR.

ABSTRACT

The upper Mesozoic and Cenozoic sedimentary series 

within about 20 miles on either side of the San Andreas 

fault has been mapped and systematically classified. Southwest of the fault, the sedimentary series overlies a Mesozoic 

crystalline basement of plutonic and metamorphic rocks, is 

from 5,000 to 40,000 feet thick, and is divided into four 

lithologic sequences. Northeast of the fault, the sedimentary 

series overlies a Mesozoic basement of eugeosynclinal rocks 

(Franciscan rocks and serpentine), is from 25,000 to 40,000 

feet thick, and is divided into five lithologic sequences. These 

sequences are in large part separated by regional unconformities. The Cretaceous and Tertiary sequences are marine 

and terrestrial southwest of the fault, marine northeast of 

it. The youngest sequence, mainly of Quaternary age, is 

composed of lithologically similar valley sediments on each 

side of the fault.

Most of the sedimentary sequences are divided into lithologically distinct formations of large areal extent, some of 

which in turn are divided into local members. A standardized 

set of names has been designated for the formations and 

members for this region, using the existing names that are 

applicable.

On opposite sides of the San Andreas fault, not only are 

the basement rocks contrasting, but the oldest corresponding sedimentary sequences are dissimilar; the successively 

younger sequences are progressively less different. This condition appears to be the result of persistent right-lateral 

movement on the fault since Cretaceous time.

INTRODUCTION

SCOPE AND PURPOSE

The areal geology of about 20 miles on either side 

of an 80-mile segment of the San Andreas fault 

from Cholame and Avenal to Cuyama and Maricopa (fig. 1) has been mapped and compiled at a 

scale of 1:125,000, or 2 miles to 1 inch (Dibblee, 

1973b). The region mapped is in the southern 

Coast Ranges and includes the extreme southeastern 

part of the Diablo Range, all the Temblor Range, 

Carrizo Plain, Caliente and La Panza Ranges, 

Sierra Madre Mountains, and much of Cuyama 

Valley (fig. 2).

The subsurface geology of this area based on the 

areal geology mapped and on logs of test holes

122 120°

FIGURE 1. Index map of part of central California. Area 

studied, indicated by dashed outline, is shown in figure 2.

drilled for oil or gas is shown in five cross sections 

(Wagner and others, 1973). The purpose of the 

geologic map (Dibblee, 1973b) and cross sections 

(Wagner and others, 1973) is to portray the regional geology and to provide a geologic background 

for earthquake investigations and geophysical 

studies in progress or contemplated along this great 

active fault.
STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

EXPLANATION

Upper Tertiary sedimentary sequence

Middle Tertiary sedimentary sequence

Lower Tertiary marine 

sedimentary sequence

Upper Cretaceous and 

lower Tertiary marine 

sedimentary sequence

Upper Jurassic (?) and 

Cretaceous marine 

sedimentary sequence

Eugeosynclinal sedimentary and igneous rocks

Crystalline plutonic and 

metamorphic rocks

Contact

Fault

Dotted where concealed 

or inferred

FIGURE 2. Distribution of major sequence in the Southern Coast Ranges near the San Andreas fault from Cholame and

Avenal to Cuyama and Maricopa.

The .purpose of this report is to supplement the 

description of the rock units on the geologic map 

(Dibblee, 1973b) with a discussion of their stratigraphy in this region. To resolve the problems in

terminology, it was necessary to (1) designate the 

major and minor lithostratigraphic units that are 

physically recognizable and mappable throughout 

the region, (2) review the stratigraphic name or
INTRODUCTION

names that have been applied to each unit by previous investigators, and (3) suggest the best designation for each unit.

PROBLEMS OF STRATIGRAPHIC TERMINOLOGY 

The map area (fig. 2) is one in which the Mesozoic and Cenozoic stratigraphy is exceedingly complex because of many unconformities and lateral 

variations in lithology and thickness resulting from 

deposition concurrent with tectonic movement. During pioneer geologic investigations of the oil and 

gas districts of this region in the early twentieth 

century, attempts were made to delineate major 

stratigraphic units on the basis of reconnaissance 

mapping. Later, more detailed investigations revealed stratigraphic complexities not recognized in 

the earlier investigations. Correlation problems became evident and led to the naming of numerous 

local stratigraphic units. As a result, each district 

has its own set of locally recognized stratigraphic 

units, and no major regional stratigraphic units of 

the California Coast Ranges have been established. 

Thus, the stratigraphic terminology is somewhat 

chaotic.

The most practical approach to regional mapping 

was to recognize and map the major stratigraphic 

divisions with a characteristic lithology of regional 

extent. These are informally designated herein as 

sedimentary "sequences" and shown in figure 3. 

Their areal extent is shown in figure 2. All are in 

large part separated by unconformities. The uppermost sequence is terrestrial; the other sequences 

are all or largely marine. Each marine sequence 

represents a complete or nearly complete sedimentary cycle of marine transgression, inundation, and 

regression. These sequences are divided into mappable units designated as lithologically distinct 

formations. Where convenient, these in turn are 

divided into local units, such as members or fades. 

This report discusses the pertinent terminology and 

evidence for the age of each stratigraphic unit, as 

well as discrepancies and problems involved.

In figure 3 and in those figures that follow, time 

boundaries of the standard European systems and 

series are suggested only by queries. Definite boundaries are not shown because of (1) uncertainties in 

the definitions of the European series or epochs, 

(2) uncertainties involved in the assignment of the 

faunal stages and "ages" to those epochs, and (3) 

uncertainties of correlation of the terrestrial vertebrate "ages" with the marine molluscan "ages" 

and microfaunal stages of the Pacific Coast region. 

The resolution of these controversial correlation 

problems is beyond the scope of this report; hence 

the queries.

AGE

0

O 

M

O

z

LJ

O

O

O

s

CO 

UJ

s

1X

£K

<<

?

o:

H

cr

LU1-

Pleistocene

??

Pliocene

??

Miocene

Oligocene

??

Eocene

??

Paleocene

CRETACEOUS

CRETACEOUS

AND

OLDER

SOUTHWEST OF SAN

ANDREAS FAULT TO

RINCONADA FAULT

NORTHEAST OF SAN

ANDREAS FAULT TO

SAN JOAQUIN VALLEY

Surficial deposits

-v_x-\/-^_/ v_^\^-^x~v_/-S_x--v_x

Valley deposits

Upper Tertiary

sedimentary

sequence

(terrestrial and

marine)

 v^x-v^-~V^ 

Middle Tertiary

sedimentary

sequence

(marine terrestrial

and volcanic)

(Absent)

Upper Cretaceous

and lower Tertiary

marine

sedimentary 

sequence

 -^ 

(Absent)

Crystalline

Plutonic and

metamorphic

rocks

Upper Tertiary

sedimentary

sequence

(marine)

V_/~v^ 

Middle Tertiary

sedimentary

sequence

(marine)

Lower Tertiary

marine 

sedimentary

sequence

 ^^^v^^^-^^^^V-x^s.

(Absent) \

Upper Jurassic(?) 

and Cretaceous

marine 

sedimentary

sequence

Eugeosynclinal

sedimentary

and igneous

rocks

FIGURE 3. Major Mesozoic and Cenozoic sedimentary sequences of the southern Coast Ranges near the San Andreas 

fault from Cholame and Avenal to Cuyama and Maricopa. 

Regional unconformities indicated by wavy lines.

CHRONOLOGY USED

Each stratigraphic unit is assigned to the "ages" 

and (or) stages currently recognizable in California 

on the basis of stratigraphic and paleontologic evidence. Tentative correlations from one chronology 

to another are indicated in figure 4 by horizontal 

dotted lines. Assignment of the units to the standard European series is controversial and not yet 

definitely resolved.

The terrestrial mammalian "ages" in figure 4 are 

those proposed by Wood and others (1941) and by 

Savage, Downs, and Poe (1954), with modifications 

by Evernden, Savage, Curtis, and James (1964). 

None were defined with reference to type sections. 

Volcanic samples from rock units within each "age" 

have been radiometrically dated by Evernden, Savage, Curtis, and James (1964) and Turner (1970),
STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

< 

sr 

u

CENOZOIC

MESOZOIC

SYSTEM

*£

r- £

zz

CX

TERTIARY

<i> CL Q.

ID

<l>

 a 

 o

^

<5 

o

CRETACEOUS

*%

^ e/j -> <

SERIES

Holocene

Pleistocene

Pliocene

Miocene

Oligocene

Eocene

Paleocene

Upper

Lower

Upper

Middle

Lower

Upper

Lower

Upper

Middle

Lower

Upper

Lower

Upper

Lower

Upper

MAMMALIAN "AGES"

Rancholabrean

Irvingtonian

Blancan

Hemphillian

Clarendonian

Barstovian

Hemingfordian

Arikareean

RADIOMETRIC 

AGES 1

I 5 .............

4 

10 ........... ?

12?---?

13? 

14

&=***

21 ..--.._

 2£.o

1C

Maestrichtian 

Campanian w 

Santonian w 

Coniacian ^ 

Turonian iCenomanian w 

Albian 

Aptian 

Barremian ^ 

Hauterivian w

Valanginian 0- 

_ . o Bernasian ^

;.) 

u 

Tithonian

FORAMINIFERAL 

STAGES

"Delmontian" 2 

Mohnian

Luisian

Relizian

Saucesian

Zemorrian

Refugian

Narizian

Ulatisian

Penutian

Bulitian

Ynezian

MOLLUSCAN "AGES"

"Upper 

Pleistocene"

"Lower 

Pleistocene"

"San Joaquin" 

and "Etchegoin"

"Jacalitos"

"Santa 

Margarita"

"Temblor"

"Vaqueros"

"Gaviota"

"Tejon"

"Domengine"

"Capay"

"Meganos"

"Martinez"

1 Potassium-argon dates in millions of years (Evernden and others, 1964, and Turner. 1970). 

2Now considered part of Mohnian Stage (R. L. Pierce, oral commun., 1970)

FIGURE 4. Cretaceous and Cenozoic chronology of the southern Coast Ranges. Diagonal dotted lines indicate correlations with the standard European series (Durham, 1954, fig. 3; Savage and others, 1954, fig. 10); horizontal 

dotted lines indicate questionable but tentative correlations.
CRYSTALLINE PLUTONIC AND METAMORPHIC ROCKS

who determined the approximate age in millions of 

years of the boundaries of those "ages." Correlation 

of the "age" boundaries with the standard European series as inferred by Durham (1954, fig. 3) and 

Savage, Downs, and Poe (1954, fig. 10) is indicated 

in figure 4. Figure 4 is based on the correlation by 

Turner (1970, fig. 9) of the mammalian "ages" with 

the foraminiferal stages and on the currently accepted assignment of those stages and correlative 

molluscan ages to the European series.

The marine foraminiferal stages assigned to the 

middle Tertiary system were proposed and defined 

by Kleinpell (1938), and those assigned to the lower 

Tertiary were proposed and defined by Mallory 

(1959). Correlation of the middle Tertiary stages 

with corresponding mammalian "ages" is adopted 

from Turner (1970, fig. 9), who radiometrically 

dated the approximate boundaries of most of those 

stages as well as those of the mammalian "ages." 

Assignment of the foraminiferal stages to the European series is adopted from Weaver and others 

(1944, chart 11), with modifications from Bandy 

and Arnal (1969, p. 786).

Marine molluscan "ages" have been proposed or 

listed but never adequately defined. Those shown 

are the ones currently recognized for the southern 

Coast Ranges by W. O. Addicott (oral commun., 

1970). Assignment of those ages to the European 

series is modified after Weaver and others (1944, 

chart 11). Those assigned to the Quaternary and 

upper Tertiary are listed by Durham (1954, ch. 3, 

p. 25); those to the middle Tertiary were proposed 

by Corey (1954, ,p. 82), and those to the lower Tertiary, by Clark and Yokes (1936).

Fossils have been reported from only very few 

places in the Mesozoic rocks; so, only a very general 

assignment of their ages to the European systems 

and stages can be inferred. Lack of microfaunal data 

from these rocks precludes their assignment to the 

foraminiferal stages proposed by Goudkoff (1945) 

and recognized by Church (1968).

TECTONIC AREAS

The region discussed in this report (fig. 2) is 

divisible by the San Andreas fault or some of its 

strands into two tectonic areas of dissimilar basement rocks and sedimentary sequences. The area 

on the northeast, which has a basement of eugeosynclinal sedimentary and igneous rocks, extends 

into the San Joaquin Valley. The area to the southwest, which is part of the Salinia block of Reed 

(1933, p. 12, fig. 16), has a basement of crystalline 

rocks and extends to the Rinconada fault (fig. 2). 

Much of the Rinconada fault as shown is commonly

assumed to be the Nacimiento fault (Vedder and 

Brown, 1968). Recent mapping by the writer, however, reveals that the Rinconada fault as shown in 

figure 2 is continuous to the northwest not with the 

Nacimiento fault of Taliaferro (1943) but with the 

Rinconada fault (Jennings, 1958) northwest of 

Atascadero. Southeastward from Atascadero, however, the Rinconada fault (fig. 2) is largely within 

the Sur-Nacimiento fault zone as defined by Page 

(1970).

It is noteworthy that not only do these two juxtaposed tectonic areas have contrasting basement 

rocks, but they also have dissimilar sedimentary 

sequences; the successively younger corresponding 

sequences are progressively more similar (fig. 3). 

This dissimilarity is interpreted to be the result of 

recurrent or continuous lateral movements on the 

San Andreas fault during or after deposition of 

each sedimentary sequence since Cretaceous time, 

as inferred by Hill and Dibblee (1953, p. 445-449) 

and discussed further at the end of this report.

CRYSTALLINE PLUTONIC AND 

METAMORPHIC ROCKS

In the Salinia block of Reed (1933) between the 

San Andreas and Rinconada faults, the Cretaceous 

and Cenozoic sedimentary rocks are underlain by a 

crystalline basement complex of plutonic and metamorphic rocks. The basement is exposed extensively 

in the northern part of the La Panza Range, where 

it is composed of massive granitic rocks, mainly 

granodiorite. These rocks were formerly thought 

to be of Jurassic age or older on the basis of their 

supposed correlation with granitic rocks of that age 

in the Sierra Nevada (Reed, 1933, p. 86). However, 

the granitic rocks of the La Panza Range are now 

considered to be about 80.5 million years old, or 

Late Cretaceous (Turonian Stage), on the basis of 

radiometric dating (Curtis and others, 1958; Hay, 

1963, p. 113), if this is the age of the emplacement 

of these rocks and not a later event.

The most southeasterly exposure of crystalline 

rocks in La Panza Range (10 miles west of Soda 

Lake, fig. 2) shows mainly gneissic rocks, including 

quartzite and marble, metamorphosed from preexisting rocks of Mesozoic age or older. In the Hed 

Hills, gneissic quartz diorite, probably metamorphosed from similar preexisting rocks, is exposed.

Plutonic rock exposed at Gold Hill, about 8 miles 

north of Cholame, is an amphibolite composed of 

hornblende quartz gabbro. It is probably an amphibolite facies of the plutonic rocks exposed west of 

the fault, as is suggested by an inclusion of marble.

495-417 O - 73 - 2
STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

The gabbro has been radiometrically dated as about 

143 million years old, or Jurassic in age (Hay, 1963, 

p. 113).

EUGEOSYNCLINAL SEDIMENTARY AND 

IGNEOUS ROCKS

DEFINITION

Northeast of the San Andreas fault (with the 

exception of Gold Hill in Cholame Valley), the lowest major rock division is a generally unmetamorphosed but severely deformed assemblage of eugeosynclinal sedimentary and mafic igneous rocks. It 

forms the basement complex upon which the upper 

Mesozoic and Cenozoic miogeosynclinal sedimentary 

sequences rest. The sedimentary and volcanic rocks 

that make up most of this assemblage are known 

informally as Franciscan rocks (Bailey and others, 

1964). Ultramafic igneous rocks intruding the 

Franciscan rocks form part of the eugeosynclinal 

complex.

Exposures of the eugeosynclinal assemblage in 

the Temblor Range are the southeasternmost in the 

Coast Ranges northeast of the San Andreas fault. 

This assemblage is exposed extensively in the Diablo 

Range to the northwest, mostly beyond the map 

area.

FRANCISCAN ROCKS

As in other parts of the Coast Ranges province, 

the Franciscan rocks, as designated by Bailey, Irwin, 

and Jones (1964, figs. 1, 2, 3; pi. 1), form an 

assemblage of eugeosynclinal marine sedimentary 

and mafic volcanic rocks many thousands of feet 

thick. The assemblage is composed of graywacke, 

claystone, basalt (greenstone), and small lenses of 

varicolored chert and limestone. These rock types, 

together with the mafic intrusive rocks, form numerous commonly brecciated lenticular masses of all 

sizes in a pervasively sheared "matrix" of dark 

claystone and fragmented graywacke. It is not 

known how or when this assemblage became so intensely deformed. This deformation may have resulted from severe tectonic movements such as 

underthrusting, accompanied by the numerous injections of ultramafic rocks, during or soon after 

deposition. These violent events appear to have 

occurred prior to deposition of the superjacent 

Jurassic (?) and Cretaceous marine sedimentary sequence because it is unaffected by pervasive shearing, mixing, and shattering.

The age within the Mesozoic Era of the Franciscan rocks of this region is controversial. Foraminifera from limestone east of Cholame Valley suggest 

a middle Cretaceous age (Dickinson, 1966a, p. 718-

719), yet the lowest units of the superjacent sedimentary sequence in the Diablo Range contain fossils inferred to indicate Early Cretaceous age. The 

Franciscan of western California is generally considered to range in age from Late Jurassic (Tithonian) to Late Cretaceous (Turonian) only on the 

basis of fossils from a few localities (Bailey and 

others, 1964, p. 122). The age relationship of the 

Franciscan to the crystalline basement complex 

across the San Andreas fault is not definitely known.

ULTRAMAFIC ROCKS

In the area within figure 2, the uliramafic rocks 

are composed mainly of serpentine and partly of 

serpentinized peridotite. They are intricately associated with Franciscan rocks in the form of numerous lenticular sill-like masses, some large, either 

intrusive or injected into the Franciscan rocks. 

Many are at or near the top of this assemblage in 

contact with the overlying Jurrassic(?) and Cretaceous marine sedimentary sequence, but none are 

found within that sequence. All the serpentinous 

masses are pervasively sheared or shattered, either 

because of expansion that occurred as a result of 

serpentinization, because of tectonic movements, or 

both. These ultramafic rocks are presumably Early 

Cretaceous and (or) possibly Late Jurassic in age.

JURASSIC(?) AND CRETACEOUS MARINE 

SEDIMENTARY SEQUENCE

DEFINITION

Northeast of the San Andreas fault, the eugeosynclinal sedimentary and igneous rocks are overlain by or are in fault contact with a sequence of 

miogeosynclinal marine clastic sedimentary rocks 

chiefly of Cretaceous age. This sequence is herein 

designated the Jurassic (?) and Cretaceous marine 

sedimentary sequence. It is the same major unit as 

that referred to by Bailey, Irwin, and Jones (1964, 

p. 123-124) as the Great Valley sequence. It was 

informally named for the Great Valley, west of 

which it is thickest. The term "Great Valley sequence" is somewhat inappropriate because the 

entire sequence is marine and was not deposited in 

a valley, as this seemingly descriptive term implies. 

Within the region of figure 2, this sequence is from 

7,000 to 10,000 feet thick and is composed of sandstone, shale, claystone, and small lenses of conglomerate. It accumulated probably under open-sea conditions offshore from a landmass, as suggested by 

scarcity of megafossils and lack of terrestrial beds. 

Three divisions are recognizable: in ascending order, 

the Gravelly Flat Formation, Hex Claystone, and 

Panoche Formation (fig. 5).
JURASSIC (?) AND CRETACEOUS MARINE SEDIMENTARY SEQUENCE

AGE

CRETACEOUS

Late

? 

Early

o

CRETACEOUS 

AND 

JURASSIC(?)

SOUTHEASTERN TCMQI r»o OAM/-C 

DIABLO RANGE TEMBLOR RANGE

Clay shale

Sandstone

c"^

\

\. (Absent)

Clay shale ^^

_ . -r- PANOCHE FORMATION

Clay shale ~~~~ -=""

s 

 s. 

Conglomerate"^"^-- --._

Sandstone ~~~.Z=»-

_ .^^ 

Clay shale

 ^-----_____HEX CLAYSTONE

GRAVELLY FLAT FORMATION

FRANCISCAN ROCKS AND SERPENTINE

CRETACEOUS JURASSIC(?) AND SEQUENCE MARINE SEDIMENTARY 

EUGEOSYNCLINAL 

SEDIMENTARY 

AND IGNEOUS 

ROCKS

FIGURE 5. Jurassic (?) and Cretaceous marine sedimentary sequence in the southeastern part of the Diablo Range and

in the Temblor Range.

Within the area of figure 2, the age of this sequence is Cretaceous. In some places it may be as 

old as latest Jurassic, but no fossils have been 

found to demonstrate this; hence the query after 

Jurassic.

GRAVELLY FLAT FORMATION

The lowest unit of the Jurassic (?) and Cretaceous marine sedimentary sequence is prominently 

exposed in the southeastern part of the Diablo 

Range, where it consists of about 3,000 feet of thinbedded dark shale containing thin interbeds of 

brown-weathering sandstone. On the southwest 

slope of Orchard Peak, this unit was originally 

referred to by Arnold and Johnson (1910, p. 351, 

pi. 1) as the Knoxville Formation (of Diller and 

Stanton, 1894), but was mapped as part of the 

undifferentiated "Knoxville-Chico rocks." It was 

later named Badger Shale by Marsh (1960, p. 9- 

12). Farther northwest, near Parkfield (10 miles 

northwest of Cholame (fig. 1)), this shale unit was 

mapped as the lower and middle parts of the Panoche Group by Dickinson (1966a, p. 709-710, pis. 1, 

2; 1966b, p. 461-462, pi. 1). Still farther northwest, 

near Gravelly Flat east of Priest Valley (about 38 

miles northwest of Cholame or 16 miles westnorthwest of Coalinga (fig. 1)), this shale unit contains Buchia and was named Gravelly Flat Formation by Rose and Colburn (1963, p. 41).

Regional mapping within and northwest of the 

area of figure 2 reveals that this shale unit is recognizable in various parts of the Diablo Range and 

commonly contains Buchia. It would be appropriate 

to apply one name to this unit throughout its recognizable areal extent, but unfortunately different 

names have 'been applied to it in different areas. A 

type exposure should be one that is fossiliferous 

and structurally homoclinal with the top and base 

exposed; the exposure that best meets these requirements is the one east of Priest Valley. Here 

this unit was named by Rose and Colburn (1963, 

p. 41) as the Gravelly Flat Formation. Therefore 

this name is hereby applied to the lowest mappable 

commonly Buchia-bearmg predominantly shale unit 

of the Jurassic (?) and Cretaceous marine sedimentary sequence within and northwest of the area 

of figure 2.

The type section of the Gravelly Flat Formation 

was not designated by Rose and Colburn (1963), 

although they mapped the exposure of this unit 

southeast of Gravelly Flat. From Gravelly Flat this 

unit was traced farther northwest by the writer,
8 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

and type section is here designated as the spur 

extending southwest from Center Peak in the SW*4 

sec. 12 and NW*4 sec. 13, T. 20 S., R. 12 E., about 

3 miles northwest of Gravelly Flat (Priest Valley 

15' quad.) and about 16 miles west-northwest of 

Coalinga (fig. 1). There the Gravelly Flat Formation is about 2,400 feet thick. It is composed mainly 

of dark shale, including about 400 feet of brownweathering sandstone in the lowest part, in contact 

with serpentine at the base. The shale is conformably overlain by a thick conglomerate unit herein 

assigned to the base of the Panoche Formation.

According to Rose and Colburn (1963, p. 41) 

and D. L. Jones (oral commun., 1970), the lowest 

part of the Gravelly Flat Formation east of Priest 

Valley contains Buchia piochii, generally considered 

diagnostic of Late Jurassic (Tithonian) age; the 

middle part contains Buchia crassa, diagnostic of 

Early Cretaceous (Valanginian) age; and the upper 

part contains fossils suggestive of Early Cretaceous 

(Hauterivian) age.

In its exposure east of Priest Valley and also 

within the area of figure 2, the Gravelly Flat Formation is distinguishable from the overlying Panoche 

Formation by its dark-gray to olive-brown color, the 

dark-colored graywacke character of its sandstone 

interbeds, and a lack of thick light-colored sandstone 

beds. Within the area of figure 2 on the south and 

west slopes of Orchard Peak, where the unit herein 

referred to the Gravelly Flat Formation was mapped 

by Marsh (1960, p. 9-12, pi. 1) as the Badger 

Shale, the formation is about 3,700 feet thick, it 

contains two layers of tuff or bentonite, and its 

base is partly if not entirely in fault contact with 

serpentine. North of Orchard Peak this unit is 

either depositional on or in fault contact with the 

Franciscan rocks. It yielded no diagnostic fossils 

in any of these exposures, but is assigned to the 

Gravelly Flat Formation because it is lithologically 

similar to and occupies the same stratigraphic position as the type section. It is tentatively considered 

to be of the same age, but because of the absence 

of fossils, the Jurassic assignment is queried.

In the northwestern Temblor Range the Gravelly 

Flat Formation is lithologically similar to the unit 

in the Diablo Range, and no fossils were found. It 

may be over 5,000 feet thick, but its contact with 

shale of the overlying Panoche Formation is only 

arbitrarily placed at the lowest abundantly interbedded sandstones.

HEX CLAYSTONE

Pervasively sheared gray claystone is exposed in 

two places, one southeast of Orchard Peak, the

other west of Devils Den. In the former exposure 

it was named Hex Formation by Marsh (1960, p. 

6-7). The type locality was designated at Hex Hill, 

about 6 miles east-southeast of Orchard Peak. This 

name is adopted herein for this unusual formation, 

but is modified to Hex Claystone because of its 

nearly homogeneous claystone lithology.

The stratigraphic position of the Hex Claystone 

is not definitely known because (1) it is pervasively 

sheared, (2) it is bounded by faults, (3) it appears 

to have been injected as a plastic mass between 

faults into the Panoche Formation at Hex Hill and 

even into Tertiary rocks at Devils Den, and (4) it 

is lithologically similar to the claystone or clay shale 

of the Panoche Formation, but contains fossils diagnostic of a pre-Late Cretaceous age.

Marsh (1960, p. 6-7) considered his Hex Formation to be of Late Jurassic (?) age on the basis of 

marine fossils found in the Hex and to be older 

than his Badger Shale (Gravelly Flat Formation 

of this report), which he assigned to the Early Cretaceous (?). While it is possible that the Hex Claystone may have been injected from below the 

Gravelly Flat Formation, this is considered unlikely 

because no claystone has been found in that position 

in an unfaulted section. Structural evidence revealed 

from mapping on Hex Hill (Dibblee, 1972a) suggests that the Hex Claystone formed by pervasive 

shearing of the upper part of the Gravelly Flat 

Formation, possibly with some involvement of the 

Panoche Formation.

Belemnites and foraminifers from the Hex Claystone of the Hex Hill area have been considered 

suggestive of Late Jurassic, Early Cretaceous, or 

Late Cretaceous ages, and the formation was tentatively assigned a Late Jurassic (?) age (Marsh, 

1960, p. 8). Foraminifers from both the Hex Hill 

and Devils Den exposures are now, however, considered strongly suggestive of an Early Cretaceous 

(Valanginian) age (Church, 1968, p. 527). This 

age is also suggested from Buchia species found at 

both exposures (D. L. Jones, oral commun., 1970).

PANOCHE FORMATION

In the southeastern part of the Diablo Range, 

the Gravelly Flat Formation is overlain by as much 

as 7,500 feet of interbedded concretion-rich lightcolored sandstone and dark-gray clay shale or claystone of Late Cretaceous age. The contact with the 

underlying Gravelly Flat Formation is gradational, 

but in places it is marked by lenses of conglomerate 

or sandstone.

These Upper Cretaceous strata were referred by 

Arnold and Johnson (1910, p. 35-37, pi. 1) to the
UPPER CRETACEOUS AND LOWER TERTIARY MARINE SEDIMENTARY SEQUENCE

Chico Formation (of Gabb, 1869), but were mapped 

as the major part of their undifferentiated "Knoxville-Chico rocks." In the Orchard Peak area southwest of McLure Valley, these strata were divided 

by Marsh (1960, p. 12-29, pis. 1, 2) into eight local 

units mapped as formations, including the uppermost claystone unit that he referred to the Moreno 

Formation of Anderson and Pack (1915). The 

names Marsh applied to these units are not adopted 

herein because the units are not recognizable outside that area. Farther northwest, all the Cretaceous marine sedimentary sequence was referred 

by Dickinson (1966a, p. 709-710) to the Panoche 

Group.

This series of strata, of Late Cretaceous age, is 

assigned to the Panoche Formation because it includes the major part of the series mapped as the 

Panoche Formation by Anderson and Pack (1915) 

and is lithologically distinct from the part assigned 

to the Gravelly Flat Formation. It is most practical 

to differentiate the Panoche Formation on the basis 

of lithology into units that are predominantly sandstone, units that are predominantly shale or claystone, and units that are predominantly conglomerate, as shown in figure 5. No names are applied 

herein because the lateral extent of these units is 

very limited.

The uppermost clay shale unit crops out on the 

west and south sides of McLure Valley, where it is 

about 900 feet thick and is overlain unconformably by Tertiary formations. On the south side of 

the valley, this clay shale unit was referred by 

Marsh (1960, p. 28-29, pi. 1) to the Moreno Formation of Anderson and Pack (1915, p. 46-47) on the 

basis of similar lithology and microfaunal correlation. This correlation is doubtful, however, because 

the Moreno Formation, of latest Cretaceous and 

Paleocene(?) age, overlies the Panoche Formation 

north of Coalinga but is overlapped by Tertiary 

formations south of Coalinga; moreover, it is not 

known to be present within the area of figure 2, 

either on the surface or in the subsurface (R. L. 

Pierce, oral commun., 1968).

In the northwestern Temblor Range, only the 

lowest 2,000 feet of the Panoche Formation is exposed. It lies unconformably below Tertiary formations, and its contact with the underlying Gravelly 

Flat Formation is gradational and arbitrarily 

Jocated.

The Panoche Formation within the area of figure 2 contains scattered megafossils and microfossils diagnostic of Late Cretaceous age (Campanian and Maestrichtian Stages) (Marsh, 1960, 

p. 16, 21, 24, 25, 28, Orchard Peak area; Dickinson,

1966b, p. 464, Table Mountain area; D. L. Jones, 

oral commun., 1966, Cedar Creek area of northwest 

Temblor Range). In the Orchard Peak area, the 

upper half of the Panoche Formation is inferred 

from megafossils and microfossils to be mainly 

within the Campanian Stage, ranging into the Santonian and possibly into the lower Maestrichtian 

Stages (Marsh, 1960, p. 25, 28, 29). West of Reef 

Ridge the lowest shale unit of the Panoche Formation, about 7 miles southwest of Avenal, yielded an 

ammonite (found by Paul Enos) considered diagnostic of the Turonian Stage (D. L. Jones, oral 

commun., 1965).

UPPER CRETACEOUS AND LOWER

TERTIARY MARINE SEDIMENTARY

SEQUENCE

DEFINITION

Southwest of the San Andreas fault, the crystalline basement of the Salinia block is overlain by a 

very thick sequence of miogeosynclinal marine clastic 

sedimentary rocks that ranges in age from very 

Late Cretaceous through Paleocene to middle Eocene. It is designated herein as the Upper Cretaceous and lower Tertiary marine sedimentary sequence. It is extensively exposed in the La Panza 

Range and the Sierra Madre Mountains, where it 

is herein designated as marine clastic sedimentary 

rocks; a small part is exposed at the southeast end 

of the Caliente Range, where it was called Pattiway 

Formation.

This thick sequence and its paleogeographic implications were described by Chipping (1972), who 

divided it into several unnamed lithogenetic units.

MARINE CLASTIC SEDIMENTARY ROCKS

The marine clastic sedimentary rocks are a monotonous, continuously deposited series, as much as 

30,000 feet thick, of interbedded arkosic sandstone, 

siltstone, clay shale, and granitic conglomerate. 

These strata appear to be deltaic deposits derived 

from rapid erosion of a nearby granitic terrane and 

deposited in a shallow sea. This thick series is not 

named nor differentiated into formations or members because it contains no persistent distinct lithologic units other than a basal conglomerate as thick 

as 2,000 feet which overlies granitic basement in 

the La Panza Range. The marine clastic sedimentary 

rocks, together with the granitic basement exposed 

in the La Panza Range, are overlain unconformably 

by the middle Tertiary sedimentary sequence.

This series of marine clastic sedimentary rocks 

rarely contains fossils. This sequence was formerly 

thought to be of Late Cretaceous age (Eaton and
10 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

others, 1941, p. 213-214, fig. 3; Hill and others, 

1958, p. 2997; Jennings, 1958); however, a few fossils diagnostic of Late Cretaceous age were found in 

the lowest 6,000 feet of this sequence in the La 

Panza Range from 21/& to 7 miles northwest of 

Pozo and in the basal 1,000 feet near Deadman 

Flat, 24 miles southeast of Pozo. A few mollusks 

and foraminifers considered to be of Paleocene age 

were found stratigraphically higher a few miles 

southeast of Pozo, and orbitoidal foraminifers diagnostic of early to middle Eocene age were found 

still higher in the section in the Sierra Madre 

Mountains (Vedder and Brown, 1968, p. 248-249). 

Just beyond the southeast border of figure 2, the 

highest part of this series yielded mollusks diagnostic of middle Eocene age (Vedder and Brown, 

1968, p. 249-251).

At the southeast end of the Caliente Range (T. 10 

N., R. 25 W.), is exposed about 3,000 feet of marine 

clastic sedimentary rocks which there were named 

the Pattiway Formation by Hill, Carlson, and Dibblee (1958, p. 2977). This name is adopted herein 

for this unit but only for this exposure, and others 

beyond the southeast border of figure 2. In these 

exposures, the Pattiway Formation is composed of 

light-gray sandstone, gray silty shale, and a few 

thin conglomerate lenses. It is unconformably overlain by the Simmler Formation, and the base is not 

exposed. In the Caliente Range, the Pattiway Formation yielded mollusks and foraminifers considered 

to be of Paleocene age (Vedder and Repenning, 

1965).

LOWER TERTIARY MARINE SEDIMENTARY 

SEQUENCE

DEFINITION

Northeast of the San Andreas fault, the Jurassic (?) and Cretaceous marine sedimentary sequence 

is overlain unconformably or disconformably by a 

marine sedimentary sequence of early Tertiary age. 

It is designated herein as the lower Tertiary marine sedimentary sequence. It is as thick as 3,000 

feet and is composed of moderately well defined 

units of sandstone and clay shale of Eocene age; it 

includes at the top a thin unit of early Oligocene 

age exposed only at Devils Den.

All but the thin top unit of this sequence was 

formerly referred to the Tejon Formation (of Gabb, 

1869, p. XIII and p. 129, footnote) by Arnold and 

Anderson (1910, p. 67-70, pi. 1), Arnold and Johnson (1910, p. 38-39, pi. 1), and Curran (1943). 

Such a name might be appropriate, but as now used 

it is generally applied to strata that are definitely

or presumably of late Eocene age, whereas part of 

the sequence described here is older. This lower 

Tertiary sequence is composed of the units shown 

in figure 6.

LODO(?) FORMATION

On Media Agua Creek, in the Temblor Range, 

about 280 feet of rocks, predominantly clay shale, 

forms an interval between shale of the Panoche 

Formation and the Point of Rocks Sandstone. On 

the basis of microfaunas, this interval was correlated with and assigned by Mallory (1959, figs. 

3, 7) to the Lodo Formation of White (1938) (type 

locality about 35 miles northwest of Coalinga) of 

Paleocene and early Eocene age. Mallory divided 

this interval into three units: lower, middle and 

upper Lodo.

The lower Lodo, as indicated by Mallory (1959, 

p. 25-26, 30-31, 34, figs. 3, 7), is about 160 feet 

thick at Media Agua Creek and is composed of soft 

clay shale. On the basis of microfaunas he assigned 

this unit to his Ynezian and Bulitian Stages, Paleocene, with the exception of the uppermost 20 feet, 

which, together with the overlying "sandstone reef" 

(his middle Lodo), he designated as his type Penutian Stage, early Eocene. These stages assigned to 

this 160-foot-thick clay shale unit correlate it with 

the type Lodo Formation, and its assignment to that 

formation is tentatively adopted. From Media Agua 

Creek this clay shale unit appears to extend southeastward along strike for an unknown distance, 

through poor exposures, possibly as far as Carneros 

Creek or Salt Creek. Northwest of Media Agua 

Creek it laps out.

Mallory (1959, p. 28, 37, fig. 7) suggested that 

a similar shale unit underlying the Avenal ("Mabury") Sandstone in the Devils Den area may be 

of Paleocene and early Eocene ages, and he assigned 

it to the Lodo Formation. Foraminifera suggestive 

of those ages have been reported from a thin shale 

unit above the Panoche Formation from several 

wells in the Devils Den area (H. C. Wagner and 

others, unpub. data).

Mallory's middle Lodo at Media Agua Creek is 

considered to be the Avenal Sandstone, and his 

upper Lodo the Gredal Shale Member of the Kreyenhagen Shale, for reasons discussed under "Avenal 

Sandstone." Their assignment to the Lodo Formation is therefore not adopted.

AVENAL SANDSTONE

In the Reef Ridge area, northwest of McLure 

Valley, the basal Tertiary sandstone unit was named 

Avenal Sandstone by Anderson (1905, p. 164, pi. 34,
LOWER TERTIARY MARINE SEDIMENTARY SEQUENCE 11

AGE

Oligocene

CD

CD

O

O

L±J

CD

ro""

CD

i

<s

L±J

Paleocene

STAGE

Refugian

Narizian

Ulatisian

Penutian

Bulitian

Ynezian

SOUTHEASTERN 

DIABLO RANGE

Absent

Point of 

Rocks

Sandstone

(Absent?)

REEF RIDGE 

AREA

DEVILS DEN TEMBLOR 

AREA RANGE

Wagon Wheel 

Formation

(Absent)

Welcome Shale

Member

Kreyenhagen

Shale

Point of 

Rocks

Sandstone

Gredal Shale Member ./

Avenal Sandstone J^ (Absent)

(Absent) \ |_odo(?) Formation X

CO 0)

-Eg

io « 

E a

ro >

0} *->

L_ C

V <"

« E

-J w

FIGURE 6. Lower Tertiary marine sedimentary sequence in part of the Diablo Range between McLure and Cholame Valleys

and in the Temblor Range. Unconformity indicated by wavy line.

fig. 1) for Avenal wells in Big Tar Canyon, 6 miles 

southwest of Avenal (fig. 2). This sandstone was 

assigned to the Domengine Formation (of Anderson, 1905, north of Coalinga) by Clark (1929, p. 

216) and Gester and Galloway (1933, p. 1167,1184). 

The Avenal Sandstone, which contains orbitoid 

Foraminifera and abundant mollusks, was mapped 

and described in detail by Stewart (1946, p. 89-94, 

pi. 1), who adopted the name and suggested its 

correlation with the Domengine Formation, which 

is very similar and is probably the same unit. The 

Avenal Sandstone is from 300 to 500 feet thick and 

fine grained, and it contains abundant mollusks 

assigned to the middle Eocene (Stewart, 1946, p. 

92-94). It was questionably assigned to the Ulatisian 

Stage, middle Eocene, by Mallory (1959, p. 51, 

fig. 7).

In areas south and southeast of McLure Valley, 

the basal Tertiary sandstone discussed in the next 

three paragraphs is herein included in the Avenal 

Sandstone because of generally similar lithology 

and probably similar stratigraphic position. Local 

names have been applied to this sandstone because 

of uncertainty of its correlation with the type Avenal Sandstone.

In the Diablo Range west of McLure Valley, this 

basal sandstone is as thick as 400 feet and was 

called Acebedo Sandstone by Dickinson (1963, p. 

48-52). This sandstone contains <(Spiroglyphus" 

and orbitoid Foraminifera, and according to Mallory (1959, p. 50-51), it is slightly older than the 

type Avenal Sandstone and was assigned by him 

to the Ulatisian or Penutian Stage, middle or lower 

Eocene.

In the Devils Den area, the lowest Tertiary sandstone unit, as thick as 200 feet, contains "Spiroglyphus" (Rotularia) and was named Mabury 

Sandstone by Van Couvering and Alien (1943, p. 

496-500). Mallory (1959, p. 37, fig. 7) assigned 

this sandstone to the Lodo Formation and to his 

Penutian Stage, lower Eocene.

In the Temblor Range between Media Agua and 

Carneros Creeks, the lowest Tertiary sandstone unit 

forms a lens as thick as 300 feet. It is underlain by 

clay shale of the Lodo Formation and is overlain 

by the Gredal Shale Member of the Kreyenhagen 

Shale. According to Durham (1942, p. 503-510), 

this sandstone contains (in NE^4SE^4 sec- 28, T. 

28 S., R. 19 E., east of Media Agua Creek) mollusks 

and corals referred to the Domengine Stage, middle
12 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Eocene. However, at Media Agua Creek, where the 

sandstone unit is only 25 feet thick, Mallory (1959, 

p. 24, 34, fig. 7) designated the sandstone (his middle Lodo) and 20 feet of the underlying shale as his 

type Penutian Stage, lower Eocene; he correlated 

the sandstone, which there contains "Spiroglyphus" 

and orbitoid foraminifers, with the Mabury Sandstone of Devils Den and assigned both to the Lodo 

Formation.

This assignment is not adopted because at Media 

Agua Creek this 25-foot-thick "sandstone reef" is 

overlain by about 90 feet of clay shale which Mallory (1959, p. 30, fig. 3, 7) designated as upper 

Lodo but which he assigned to his Ulatisian Stage, 

middle Eocene. This assignment would correlate 

this shale with the Gredal Shale Member of the 

Kreyenhagen Shale. The underlying "sandstone 

reef" is therefore probably the same unit as the 

Avenal Sandstone, to which it is assigned.

Although there is some doubt as to exact correlation, the Acebedo Sandstone west of McLure Valley, 

Mabury Sandstone of Devils Den, and the sandstone 

at Media Agua Creek are herein assigned to the 

Avenal Sandstone because in each area they are of 

generally similar lithology and form the basal transgressive sandstone unit of the lower Tertiary marine 

sedimentary sequence; thus they appear to be the 

same unit. Therefore the local names Acebedo and 

Mabury are not formally adopted. The Avenal Sandstone, as herein mapped, is presumably in the Domengine molluscan age and Fenutian and Ulatisian 

Stages, early and middle Eocene.

KREYENHAGEN SHALE

The clay shale and claystone facies of the lower 

Tertiary marine sedimentary sequence is prominently exposed in the Reef Ridge area north of 

McLure Valley. It was named Kreyenhagen Shale 

for Kreyenhagen wells at Canoas Creek (7 miles 

west of Avenal), the type locality, by Anderson 

(1905, p. 163-168). This name was not used by 

Arnold and Anderson (1910, p. 58-70) but was 

adopted by Cushman and Siegfus (1942), who described the sections exposed at Canoas and Garza 

Creeks (7 miles west of Avenal) and by Stewart 

(1946, p. 95, pi. 1), who described and mapped the 

formation in detail.

In the Reef Ridge area the Kreyenhagen Shale 

is from 950 to 1,250 feet thick, consists of gray 

clayey to silty shale, overlies the Avenal Sandstone, 

and is unconformably overlain by the Temblor 

Sandstone. The major part of the Kreyenhagen 

Shale contains foraminifers diagnostic of the Narizian Stage, late Eocene (Mallory, 1959, p. 71, fig. 7). 

Cushman and Siegfus (1942, p. 395-397) suggested

that the upper part may be as young as Oligocene 

(Refugian). The lowest 50-110 feet of the Kreyenhagen Shale is greenish claystone which was named 

the Canoas Siltstone Member by Cushman and Siegfus (1942, p. 390-391) and which contains a foraminiferal fauna ("Canoas Fauna") to which they 

assigned a middle Eocene age. Mallory (1959, p. 51, 

71) suggested that this fauna may belong to his 

Ulatisian Stage, middle Eocene, but it is not certainly diagnostic.

In the Devils Den area the Kreyenhagen Shale is 

separated into two units of clayey shale by the 

Point of Rocks Sandstone (fig. 6). The lower unit, 

as thick as 700 feet, was named the Gredal Formation by Van Couvering and Alien (1943, p. 496- 

500). This same unit was designated as the Gredal 

Member of the Lodo Formation and assigned to the 

Ulatisian Stage, middle Eocene, by Mallory (1959, 

p. 45, 51, fig. 7), but it was mapped as the Canoas 

Siltstone Member of the Kreyenhagen Shale by 

Marsh (1960, p. 31, pi. 1). Because this unit is much 

thicker than the type Canoas Siltstone Member of 

Reef Ridge (too thin to show at the map scale), 

with which it is correlated by petroleum geologists, 

the unit at Devils Den is herein adopted as the 

Gredal Shale Member of the Kreyenhagen Shale. 

The type section of this member is designated as 

the section exposed in NE*4 sec. 10, T. 26 S., R. 

18 E., 4 miles south of Devils Den, where it consists 

of about 750 feet of gray clayey shale with local 

occurrences of green and red clay, overlies the Avenal ("Mabury") Sandstone, and is overlain by the 

Point of Rocks Sandstone.

In the northwestern Temblor Range, the Gredal 

Shale Member of the Kreyenhagen Shale is exposed 

south of Cedar Creek and at Media Agua Creek 

(fig. 9). In the former area, it is several hundred 

feet thick and consists of gray, green, and red claystone that unconformably overlies the Gravelly Flat 

Formation. At Media Agua Creek, it overlies the 

Avenal (?) Sandstone and is overlain by the Point 

of Rocks Sandstone, as at Devils Den; it is about 

90 feet thick and is the same unit as the upper Lodo 

of Mallory (1959, p. 24, 45, figs. 3, 7), which he 

assigned to his Ulatisian Stage, middle Eocene.

The upper unit of the Kreyenhagen Shale in the 

Devils Den area is composed of about 600 feet of 

clayey shale that overlies the Point of Rocks Sandstone and is overlain by the Wagonwheel Formation. 

This shale unit was named Welcome Formation by 

Van Couvering and Alien (1943, p. 496-500). This 

unit is herein adopted as the Welcome Shale Member of the Kreyenhagen Shale, with the type section 

designated as Welcome Valley (SE^4 sec. 35, T. 25
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 13

S., R. 18 E., NE*4NE14 sec. 2 and NWVi sec. 1, 

T. 26 S., R. 18 E.), just south of Devils Den. This 

unit is poorly and incompletely exposed; it is concealed by alluvium to the southeast and is overlapped by the Temblor Formation to the northwest. 

It forms the upper part of the type Narizian Stage, 

upper Eocene, of Mallory (1959, p. 55-56), although foraminifers of the Refugian Stage have 

been reported from the uppermost part of this 

shale unit by Smith (1956, p. 77-78) and Mallory 

(1959, p. 71).

On the basis of the foregoing evidence, the Gredal 

Shale Member of the Kreyenhagen Shale is assigned 

to the Ulatisian Stage, middle Eocene, and the Welcome Shale Member is assigned to the Narizian 

Stage, upper Eocene, with the upper part possibly 

extending into the Refugian Stage, early Oligocene.

POINT OF ROCKS SANDSTONE

The sandstone of the Eocene sedimentary sequence 

is prominently exposed in the northwest part of the 

Temblor Range, where it is as much as 2,000 feet 

thick, near Devils Den where it is about 2,350 feet 

thick, and in the Diablo Range, where it is as much 

as 1,250 feet thick. In the Devils Den area, it was 

named Point of Rocks Sandstone, for Point of Rocks 

(Si/2 sec. 2, T. 26 S., R. 18 E.), 3 miles south of 

Devils Den, by Van Couvering and Alien (1943, 

p. 496-500). This name is adopted herein. In the 

Reef Ridge area, this sandstone either is missing 

or may be represented by a sandstone lens as thick 

as 30 feet about 100 feet above the base of the 

Kreyenhagen Shale (Dickinson, 1966a, p. 711).

The Point of Rocks Sandstone rarely contains 

fossils. "Characteristic Tejon fossils" were reported 

but not listed from the Point of Rocks area by 

Arnold and Johnson (1910, p. 38). At Devils Den, 

the Point of Rocks Sandstone, with the possible 

exception of the lowest 75 feet, was designated as 

the type Narizian Stage, upper Eocene, by Mallory 

(1959, p. 55-56). Foraminifers diagnostic of the 

Narizian Stage were obtained from thin shale beds 

in this sandstone at Devils Den and also at Media 

Agua Creek by Mallory (1959, p. 56). At Devils 

Den, shale interbeds in the lowest 75 feet of the 

Point of Rocks Sandstone contain foraminifers assigned by Mallory (1959, p. 57) to the Ulatisian 

Stage. The basal part of the Point of Rocks Sandstone is thereby assigned to the Ulatisian Stage, 

middle Eocene, and the major part to the Narizian 

Stage, upper Eocene.

WAGONWHEEL FORMATION

In the Devils Den area, a basal marine sandstone 

and a clayey shale unit, about 500 feet thick, were

mapped as Oligocene (?) rocks by Arnold and Johnson (1910, p. 40). Johnson (1909, p. 63) had previously named this unit the Wagonwheel Formation 

for exposures near Wagonwheel Mountain, 2 miles 

south of Devils Den, and had tentatively assigned 

it to the Oligocene. This name was used by Van 

Couvering and Alien (1943, fig. 213) and is adopted 

herein. Atwill (1935, p. 1207) correlated this unit 

with his Tumey Formation north of Coalinga.

The Wagonwheel Formation and its foraminiferal fauna were described and discussed in detail 

by Smith (1956). He assigned the formation to the 

Refugian Stage of early Oligocene age and indicated 

that it lies conformably on the Kreyenhagen Shale 

and disconformably below the Temblor Formation. 

Because of these stratigraphic relationships, this 

unit, which is the only one wholly assigned to the 

Refugian Stage within this region, is placed arbitrarily at the top of the lower Tertiary marine sedimentary sequence, rather than in the middle Tertiary sedimentary sequence.

MIDDLE TERTIARY SEDIMENTARY 

SEQUENCE

DEFINITION

The middle Tertiary sedimentary sequence is extensive on both sides of the San Andreas fault. It 

lies unconformably on the older rock units in most 

areas and is lithologically more variable than the 

other sedimentary sequences. It represents a complete sedimentary cycle of transgression, inundation, and regression. This sequence is mainly of 

Miocene age, but it is in part Oligocene and possibly 

in part Pliocene.

Southwest of the San Andreas fault, this sequence 

is as thick as 10,000 feet in the central part of the 

Caliente Range and probably equally as thick under 

the Carrizo Plain. Within a few miles the whole 

sequence thins to the northwest, southwest, and 

southeast to about 2,500 feet or less, with a few 

local unconformities within it. The lowest unit of 

this sequence is terrestrial, the remainder is marine; 

much of this marine part grades laterally northeastward into terrestrial deposits apparently derived 

from a granitic terrane that existed northeast of 

the San Andreas fault in middle Tertiary time. 

Most of the marine facies is sandstone and some 

argillaceous sediments, but the middle part in areas 

distant from the San Andreas fault is mostly siliceous shale. Basaltic intrusions and lava flows occur 

in both the terrestrial and marine facies in the 

Caliente Range. This sequence unconformably overlies the Upper Cretaceous and lower Tertiary marine 

sedimentary sequence, overlapping and truncating

495-417 O - 73 - 3
14 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

LLl

Miocene * 

Oligocene 

STAGE

Mohnian

Luisian

Relizian

Saucesian

Zemorrian

SIERRA MADRE MOUN" 

AND LA PANZA RAN

SAN"

CALIENTE RANGE, 

rAINS CARRIZO PLAIN(?), AND NORTHEAST.^

GE RED HILLS AREA

FA MARGARITA FORMATION ^^^<^___Basa\i_^>

(sandstone) "r"--.,. f- ^-^ /Basalt

I Whiterock Bluff Shale J> <^ <---"*

1 Member -= - ' -.--" BRANCH ""^ ->. ~3sasalt MONTEREY ^.--^ ^--> ,v,v/ ---J1 _==^pa*<M

SHALE 

Saltos Shale M

S VAQU 

N FORM

 SAN n^Tni\|F <"

ember <=^- " -*"-> ^ 

Basalt/ _ _ ^---r-^?' , J

-7= =~ % CALIENTE

Basalt7 «£ FORMATION 

< 

Painted Rock ^

Sandstone __- ^^ ^^^ 

EROS Member <^^ -^T ^> 

ATION - =._"""" ^--::^" ^^-^

^" Soda Lake Shale Member J^;*~ ^>- \ * '

1 Mostly *^ Quail Canyon Sandstone Member7

(Absent) \^ conglom- ^fMMLER FORMATION Mostly 

^x erate ~~^ 

x v^ <^ sandstone

UPPER CRETACEOUS AND LOWER TERTIARY MARINE 

SEDIMENTARY SEQUENCE, AND CRYSTALLINE ROCKS

| MIDDLE TERTIARY SEQUENCE SEDIMENTARY 

FIGURE 7. Lithologic units of the middle Tertiary sedimentary sequence southwest of the San Andreas fault from Cholame to Cuyama. Caliente and Simmler Formations are terrestrial; all other units marine. Unconformity indicated by 

wavy line.

it from south to north onto the crystalline rocks. 

The lithologic units that make up the middle Tertiary sedimentary sequence southwest of the San 

Andreas fault are shown in figure 7.

Northeast of the San Andreas fault, this sequence 

is virtually all marine. It attains its greatest thickness, one of the greatest in California, in the southeastern Temblor Range, where it is as thick as 

15,000 feet. In this area and adjacent parts of San 

Joaquin Valley, most of it accumulated under 

bathyal and abyssal conditions (Bandy and Arnal, 

1969, p. 794, 814). Northwestward, this sequence 

gradually thins to as little as 700 feet in the Diablo 

Range and accumulated under shallower water. The 

lower part is chiefly sandstone and argillaceous 

deposits, the upper part mainly siliceous shale. In 

the southeastern Temblor Range and adjacent parts 

of the San Joaquin Valley, this sequence lies disconformably(?) on the lower Tertiary marine sedimentary sequence, but in the northwestern Temblor 

Range and Diablo Range it becomes unconformable 

on this and the older sequences, with increasing discordance westward toward the San Andreas fault. 

In a few places local unconformities occur within 

this sequence. The lithologic units that make up the

middle Tertiary sedimentary sequence northeast of 

the San Andreas fault are shown in figure 8. The 

stratigraphic units of this sequence shown in figures 7 and 8 are discussed in the following sections.

SIMMLER FORMATION

Southwest of the San Andreas fault, the basal 

unit of the middle Tertiary sedimentary sequence 

is composed of terrestrial red to gray conglomerate, 

sandstone, and siltstone. It was named the Simmler 

Formation by Hill, Carlson, and Dibblee (1958, p. 

2981-2983, fig. 3). The name is adopted herein. This 

formation lies unconformably on and overlaps the 

Upper Cretaceous and lower Tertiary marine sedimentary sequence from south to north onto the 

underlying crystalline rocks. It is conformably overlain by the Vaqueros Formation.

In the Caliente Range, the southeastern part of 

which includes the type section from 4 to 5 miles 

northeast of Cuyama (Hill and others, 1958, p. 

2981), the Simmler Formation is about 3,000 feet 

thick and consists of hard red and greenish-gray 

well-bedded sandstone, siltstone, and local basal 

conglomerate. Its red and greenish colors and lack 

of marine fossils suggest that this formation is
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 15

STAGE SOUTHEASTERN 

DIABLO RANGE

NORTHWESTERN 

TEMBLOR RANGE

SOUTHEASTERN 

TEMBLOR RANGE

REEF RIDGE SHALE (Absent or not exposed)

BITTERWATER 

CREEK SHALE

(Absent?)

Mohnian

Belridge Diatomite Member

McLure Shale Member

SANTA MARGARITA 

FORMATION 

J^pnglpmerate) 

Sandstone 

lenses<

Luisian

Relizian

Saucesian

Devilwater Shale Member

(Absent)

SHALE

Shale and 

Gould Shale Member I sandstone

Sandstone

o <u QOC

Zemorrian

(Absent)

Conglomerate lens

TEMBLOR FORMATION

Pre-Zemorrian LOWER TERTIARY MARINE SEDIMENTARY SEQUENCE AND OLDER ROCKS

FIGURE 8. Lithologic units of the middle Tertiary sedimentary sequence northeast of the San Andreas fault from Avenal 

to Maricopa. All units are marine. Unconformities indicated by wavy lines. For named local units of Temblor Formation, see table 2 and figures 10 and 11.

entirely terrestrial and may contain some lacustrine 

beds.

In the La Panza Range and the vicinity of Cuyama 

Gorge, the Simmler Formation consists of red and 

gray coarse conglomerate and sandstone. It is as 

thick as 3,400 feet in Cuyama Gorge, but is much 

thinner in the La Panza Range. This conglomerate 

was mapped as the Redrock Canyon Member of the 

Santa Margarita Formation by English (1916, p. 

202); as the nonmarine Vaqueros Formation by 

Eaton, Grant, and Alien (1941, p. 217); as the 

Sespe Formation by Clements (1950); and as Oligocene(?) red beds by Vedder and Brown (1968, p. 

252-253). It was referred to the Simmler Formation by Hill, Carlson, and Dibblee (1958, fig. 3) 

because its stratigraphic position is the same as 

that of Simmler Formation in the Caliente Range 

and it was presumed to be continuous with that 

formation. It is, however, much coarser and contains much sandstone detritus.

The Simmler Formation is unfossiliferous, except for sparse plant remains and bone fragments. 

Its possible age range is from late Eocene to early 

Miocene. Its conformable relationship to the overlying .beds of Zemorrian Stage of the Vaqueros

Formation and unconformable relationship to the 

underlying sequence suggest that it is most likely 

Oligocene in age. It is probably mainly in the Zemorrian Stage, late Oligocene, and possibly in part 

in the Refugian Stage, early Oligocene. The Simmler 

Formation is probably correlative with the Berry 

Formation (of Thorup, 1943) of Salinas Valley and 

with the Sespe Formation (of Watts, 1897) of the 

Santa Ynez Mountains and Ventura basin on the 

basis of similar lithology and stratigraphic position.

VAQUEROS AND TEMBLOR FORMATIONS 

REVIEW OF NOMENCLATURE

Marine sandstone and argillaceous sediments, 

commonly assigned early and middle Miocene ages 

but now considered to be late Oligocene to middle 

Miocene, form all or much of the lower part of the 

middle Tertiary sedimentary sequence on both sides 

of the San Andreas fault. Two names, Vaqueros 

and Temblor, have been applied to this marine unit, 

and both have been in common usage for more than 

60 years.

The name Vaqueros was applied by Hamlin 

(1904) when he mapped sandstone exposures of 

this unit about 10 miles west of King City. This
16 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

name was also used by Fairbanks (1904) for equivalent rocks near Paso Robles. Anderson (1905) applied the name "Temblor beds" to what was later 

found to be essentially a stratigraphically equivalent 

unit in the Temblor Range. Application of both these 

names followed, as shown on table 1. In early years,

TABLE 1. Names applied by other investigators to strata 

herein assigned to the Vagueros and Temblor Formations 

of map region of figure 2

Southwest of 

San Andreas fault

Northeast of 

San Andreas fault Investigators

Vaqueros Formation ____ _ ___ Fairbanks (1904) 

Temblor beds ______-Anderson (1905, p.

170-172; 1908, p.

18-20). 

Vaqueros Formation Arnold and Anderson

(1908, p. 31-35,pl. 1;

1910. p. 80-88, pi. 1).

 _,_do____ _ __ Arnold and Johnson

(1910, p. 42-51, pi. 1). 

Temblor Group _ Anderson and Martin,

(1914, p. 37-44, pi.

10). 

Vaqueros Formation __Anderson and Pack (1915

p. 80-87). 

Vaqueros Formation.--___ ____ English (1916, p. 198-

201, pi. XIX). 

Vaqueros Formation English (1921, p. 13 21,

Pi. 1). 

Do Loel and Corey (1932, p.

45-50). 

Temblor1 and Vaqueros1 _________________Eaton (1939, p. 261-266,

pi. IV); Eaton, Grant

and Alien (1941, p.

216-230, fig. 3). 

Temblor Formation ___Kleinpell (1938, p. 104-

107, pi. 6). 

Temblor Sandstone _ Woodring, Stewart, and

Richards (1940, p.

129-144, pi. 51). 

Temblor-Vaqueros ____Simonson and Kruegrer

(1942, p. 1613-1616). 

Temblor Formation _ Curran (1943, p. 1365 

1369).

Escudo and Hannah Van Couvering and 

Formations Alien (1943, p. 496-

500). 

Vaqueros Sandstone _ Bramlette and Daviess

(1944). 

Temblor Formation ___Stewart (1946, p. 97-103,

pi. 9).

 do -Heikkila and MacLeod 

(1951, p. 5, 7-11, pi. 

1). 

___do___________Marsh (1960, p. 31-32,

Pi. 1).

Vaqueros Formation _ _ Hill, Carlson, and

Dibblee (1958, p. 

2983-2987).

Do__________ Temblor-Vaqueros Dibblee (1962, p. 9-10); 

Formation. Fletcher (1962, p.

17). 

Do ________________-__-___-- Vedder and Repenning

(1965). 

Temblor-Vaqueros Dickinson (1966a, p.

Formation. 711-713, pi. 2). 

Temblor Formation ___Foss and Blaisdell (1968, 

p. 38-41). ___

1 Used in the time-stratigraphic sense.

"Vaqueros" was used by geologists of the U.S. 

Geological Survey, and "Temblor" by F. M. Anderson of the California Academy of Sciences.

Paleontological studies of the molluscan and echinoid faunas from the "lower Miocene" strata by 

Wiedey (1928, p. 104-107) and by Loel and Corey 

(1932, p. 45-50) established the presence of two 

faunal zones, namely a lower or Turritella inezana 

zone and an upper or Turritelta ocoyana zone. Although some confusion resulted when it was found 

that Turritella ocoyana ranges downward far into

the lower faunal zone in the Caliente Range (Eaton, 

1939, pi. IV; Repenning and Vedder, 1961, p. C237), 

the faunal assemblages are distinct. Loel and Corey 

(1932, p. 45-50), Wimrarth (1938, p. 2127, 2234- 

2235), Eaton (1939, p. 259-266, pi. IV), Eaton, 

Grant, and Alien (1941, p. 216-224), and Woodring, 

Stewart, and Richards (1940, p. 129) applied the 

term Vaqueros to strata that contain fossils of the 

lower faunal zone because these fossils occur in the 

type Vaqueros Formation (of Hamlin, 1904) and 

applied the term Temblor to strata that contain 

fossils of the upper faunal zone because these fossils 

occur in most of the type Temblor Formation (of 

Anderson, 1905). These names were also applied to 

the faunal zones or "ages," when the lower faunal 

zone became known as "Vaqueros age" and the 

upper zone as "Temblor age" (Weaver and others, 

1944, chart 11; Corey, 1954, chap. Ill, fig. 9), but 

these molluscan "ages" were never defined.

Studies of the foraminiferal faunas in the "lower 

Miocene" strata by Kleinpell (1938, p. 152-155, fig. 

4) indicate that "Vaqueros age" corresponds roughly 

to his Zemorrian Stage; "Temblor age" to his late 

Saucesian Relizian and Luisian Stages; and a "transition zone" to his early Saucesian Stage.

Differentiating the "lower Miocene" marine strata 

into the Vaqueros and Temblor Formations on the 

basis of their faunal content seemed appropriate, 

but was impractical because (1) generally the lithology does not change within these strata, (2) no 

definite boundary separates the two faunal "ages," 

and (3) in many exposures fossils are scarce or 

lacking. Even in the most fossiliferous and complete 

section in the Caliente Range, the formations could 

not be differentiated with certainty on this basis 

by Hill, Carlson, and Dibblee (1958) or by Vedder 

and Repenning (1965), although the faunizones 

could be recognized.

It is here proposed that in all areas southwest 

of the San Andreas fault the name Vaqueros Formation be applied to this whole stratigraphic unit and 

that in all areas northeast of this fault the name 

Temblor Formation be applied. Because of their 

long-established usage in this manner (fig. 4), both 

names are best retained with the fault as an arbitrary boundary.

In the field this marine unit, deposited under a 

transgressing sea, is diff erentiable into two principal 

lithologic types or fades: (1) sandstone and (2) 

argillaceous sedimentary rocks variously called 

mudstone, siltstone, claystone, clay shale, silty shale, 

and shale. Where these two types are interbedded, 

the facies unit is designated by the predominant 

rock type. In some areas, especially near oil fields,
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 17

the parts of these facies that form local stratigraphic units have been named and described in 

many publications as members.

The age of the Vaqueros and Temblor Formations 

is generally regarded as early Miocene or Oligocene 

and Miocene (Weaver and others, 1944, chap. 11). 

Within the region of figure 2 both formations are 

mainly within the Zemorrian and Saucesian Stages, 

and locally the uppermost parts include the lowest 

part of the Relizian Stage, middle Miocene. The 

Zemorrian Stage is now considered equivalent to 

late Oligocene age and the Saucesian Stage to the 

early Miocene (Bandy and Arnal, 1969, p. 786). If 

this correlation is accepted, then the Vaqueros and 

Temblor Formations are late Oligocene to middle 

Miocene in age.

VAQUEROS FORMATION

Southwest of the San Andreas fault the Vaqueros 

Formation is thickest, 7,000 feet, in the central and 

northwestern parts of the Caliente Range and possibly under the Carrizo Plain. It thins southeastward to about 1,000 feet at the southeast end of the 

range, in part by intertonguing of its upper part 

into the terrestrial Caliente Formation. To the 

northwest, west, and southwest, this formation thins 

to about 1,000 feet or less under Salinas Valley and 

in the La Panza Range. In western Cuyama Valley 

and in the Sierra Madre Mountains, it is either 

absent or very thin.

In areas other than the Caliente Range, the 

Vaqueros Formation is mostly all sandstone and is 

undivided. In the Caliente Range, this formation 

was divided by Hill, Carlson, and Dibblee (1958, 

p. 2983-2988) into a local basal unit called the Soda 

Lake Sandstone Member, a lower unit called Soda 

Lake Shale Member, and an upper unit called 

Painted Rock Sandstone Member. The last two of 

these names are adopted herein; the first is renamed (fig. 7).

QUAIL CANYON SANDSTONE MEMBER

The Soda Lake Shale Member in the southeastern 

Caliente Range is underlain in large part by a thin 

sandstone unit that was called the Soda Lake Sandstone Member by Hill, Carlson, and Dibblee (1958, 

p. 2984). Because the name Soda Lake is already 

applied to the overlying shale unit, this sandstone 

unit is here renamed the Quail Canyon Sandstone 

Member of the Vaqueros Formation. It is named for 

exposures in Quail Canyon, Cuyama quadrangle, 

1964. The type locality is in the NWViSWi/i sec. 

4, T. 10 N., R. 25 W., which is the same as that

designated by Hill, Carlson, and Dibblee (1958, p. 

2984) for the Soda Lake Sandstone Member. It 

conformably overlies red beds of the Simmler Formation and was described by Hill, Carlson, and 

Dibblee (1958, p. 2984) as follows: 

The sandstone in the type section attains a maximum thickness of 300 feet. It thins westward by a probable gradation 

into Soda Lake shale and toward the southeast it becomes 

undifferentiated from the overlying Painted Rock sandstone 

(T. 10 N., R. 25 W.). At its type locality * * * the Soda 

Lake sandstone is characteristically gray-white, weathering 

to light buff, massively bedded, fine to medium grained, 

well sorted, and very firmly indurated. It is commonly 

cross-bedded with fore-set beds dipping in a westerly direction.

This sandstone member contains Pecten magnolia and other forms diagnostic of "Vaqueros age" 

(J. G. Vedder, oral commun., 1968), Oligocene. 

According to R. L. Pierce (oral commun., 1970), 

this sandstone member is probably correlative with 

the Agua Sandstone Member of the Temblor Formation, and with the Vaqueros Sandstone of the 

Santa Ynez Mountains. The Quail Canyon Sandstone Member is assigned to the late Zemorrian 

Stage, late Oligocene, on the basis of the foregoing 

evidence.

SODA LAKE SHALE MEMBER

The Soda Lake Shale Member consists of darkgray silty clay shale, claystone, and siltstone. The 

type section is in the northwestern Caliente Range 

(NE14 sec. 6, T. 31 S., R. 19 E., and extreme SE14 

sec. 31, T. 30 S., R. 19 E.), 3 miles west of the 

north end of Soda Lake (Hill and others, 1958, p. 

2983, 2985). There, it is about 1,200 feet thick and 

contains a prominent bed of chert just below the 

middle. It contains foraminifers diagnostic of the 

Zemorrian Stage (late Oligocene) below that chert 

bed and foraminifers of the Saucesian Stage (early 

Miocene) above it.

The Soda Lake Shale Member is also exposed in 

the southeastern Caliente Range, where the probable 

time-stratigraphic equivalent of the type section is 

about 900 feet thick or less. It is of the same lithology as at the type section and in one place contains a lens of chert a few feet thick, just below the 

middle. It is in part overlain by as much as 2,000 

feet of siltstone and some interbedded sandstone 

that was included in the Soda Lake Shale Member 

of this area by Vedder and Repenning (1965) because of its predominant siltstone lithology. According to them, this part contains foraminifers diagnostic of the Saucesian Stage and mollusks diagnostic 

of "Vaqueros age." Near the southeast end of this 

range, all the strata assigned to the Soda Lake Shale
18 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Member grade laterally eastward into the Painted 

Rock Sandstone Member.

According to R. L. Pierce (oral commun., 1970), 

the part of the Soda Lake Shale Member below the 

chert bed at the type section and the lowest part of 

this member in the Cuyama Valley oil fields contain 

a neritic foraminiferal fauna diagnostic of the late 

Zemorrian Stage and are probably correlative with 

the Agua Sandstone Member and part of the underlying lower part of the Santos Shale Member of the 

Temblor Formation as defined herein; the part above 

the chert bed at the type section and the upper part 

in the Cuyama Valley oil fields contain a subabyssal 

fauna diagnostic of the early Saucesian Stage and 

are probably correlative with the upper part of the 

Santos Shale Member of the Temblor Formation as 

defined herein. The faunas of the Soda Lake Shale 

Member, according to Pierce, however, are unlike 

those of the San Joaquin Valley, but are similar to 

those of the same age in the Santa Ynez Mountains. 

Thus, the basin in which this member accumulated 

was probably not connected with the San Joaquin 

Valley basin at that time, as suggested by Cross 

(1962, p. 27).

PAINTED ROCK SANDSTONE MEMBER

The Painted Rock Sandstone Member was named 

for Painted Rock, a prominent cavernous sandstone 

outcrop south of Soda Lake, but the type locality is 

the section exposed in the vicinity of Caliente Mountain, 7 miles northwest of New Cuyama (Hill and 

others, 1958, p. 2986, 2988). In the northwestern 

Caliente Range this member is nearly all sandstone, 

but at Caliente Mountain and a few miles eastward 

it includes as much as 50 percent interbedded siltstone. In these areas this member is about 5,500 

feet thick. It thins to the southeast, in part by lateral gradation of its lower beds into the Soda Lake 

Shale Member and of its upper beds into the terrestrial Caliente Formation and in part by actual 

thinning of the whole member. At the southeast end 

of the Caliente Range, the Painted Rock Sandstone 

Member is only about 600 feet thick.

The Painted Rock Sandstone Member in the 

vicinity of Caliente Mountain and southeastward 

contains abundant Turritella ocoyana and Lyropecten miguelensis, especially in its upper and middle 

parts. In other areas these species occur in sandstones of "Temblor age." Eaton, Grant, and Alien 

(1941) assigned the upper 900 feet of this sandstone unit to the "Temblor" and the rest to the 

"Vaqueros." The fauna throughout this member is 

now considered to be of "Vaqueros age," early Miocene (Repenning and Vedder, 1961). In the northwestern Caliente Range, the uppermost sandstones

of this member are somewhat higher stratigraphically than those near Caliente Peak and may be of 

"Temblor age," middle Miocene.

The Painted Rock Sandstone Member contains 

undiagnostic shallow-water foraminifers, but foraminifers diagnostic of the Saucesian Stage, early 

Miocene, occur in the underlying beds of the Soda 

Lake Shale Member and west of Caliente Mountain 

in the immediately overlying beds of the Monterey 

Shale (Vedder and Repenning, 1965).

On the northeast flank of La Panza Range, the 

Vaqueros Formation is nearly all sandstone and 

ranges from about 200 to 1,200 feet in thickness. 

It is assigned to the Painted Rock Sandstone Member because it is lithologically similar to that unit 

in the nearby northwestern Caliente Range and is 

conformably overlain by the Saltos Shale Member 

of the Monterey Shale. In most places the Painted 

Rock Sandstone Member rests unconformably on 

crystalline basement rocks or on the Upper Cretaceous and lower Tertiary sedimentary sequence, 

against which the lower beds buttress out. In other 

places this member conformably overlies conglomerate of the Simmler Formation, and at La Panza 

Canyon (in sec. 36, T. 29 S., R. 16 E.) it overlies 

a thin intervening wedge as thick as 200 feet of 

the Soda Lake(?) Shale Member of the Vaqueros 

Formation.

The upper part of the Painted Rock Sandstone 

Member of La Panza Range is generally fine grained 

and fossiliferous, with abundant fossils of the Turritella ocoyana zone of "Temblor age," lower or 

middle Miocene. The lower part is medium to coarse 

grained, nearly white, and rarely fossiliferous, although fossils of the Turritella inezana zone or 

"Vaqueros age," lower Miocene, were reported and 

listed by Loel and Corey (1932, p. 107 and correlation chart).

TEMBLOR FORMATION

In the Temblor Range the Temblor Formation is 

composed of sandstone and lesser amounts of argillaceous sedimentary rocks. In the southeastern part 

of the range, as much as 7,000 feet crops out; the 

base of this unit is unexposed. In the northwestern 

part this unit is much thinner but of variable thickness. At the northwest end of the Temblor Range 

and on the southwest flank of the Diablo Range near 

Cholame Valley, the Temblor Formation is nearly 

all sandstone and is 0-5,000 feet thick but generally 

less than 2,000 feet. At one place about 5 miles 

northeast of Cholame, the Temblor Formation contains a lens, as much as 500 feet thick, of terrestrial 

red beds, as mapped by Dickinson (1966a, p. 711, 

pi. 1). At a locality 7 miles slightly south of east
T. 27 S

T. 285.

R.18 E.

MIDDLE TERTIARY SEDIMENTARY SEQUENCE

R.19E. R. 20 E.

19

R. 21 E.

T. 29 S.

\\ North 

\ \ Antelope Hills 

'. Voil field

-i-fr"' '-., \ Antelope Hills 

N. 'voil field

McDonald Anticline oil field

EXPLANATION

Point of Rocks Sandstone

Pre-Tertiary rocks

Temblor Formation

FIGURE 9. Part of the Temblor Range showing geographic localities mentioned and areal extent of the Tertiary formations.

of Cholame, the formation contains a basal conglomerate lens as thick as 500 feet. The Temblor 

Formation is largely absent in the McLure Valley 

area, but is present at Devils Den and Reef Ridge.

Throughout the central and northwestern parts 

of the Temblor Range and adjacent part of the 

Diablo Range, the Temblor Formation rests either 

disconforambly or unconformably on the lower Tertiary, Cretaceous, and Franciscan rocks, overlapping

them from northeast to southwest with increasing 

discordance toward the San Andreas fault.

In most places the Temblor Formation is differentiable only into its facies of (1) sandstone, (2) 

argillaceous sedimentary rocks, and (3) basal conglomerate (in one area only). These are unnamed; 

however, on the northeast flank of the central part 

of the Temblor Range between Salt Creek and Bitterwater Creek (fig. 9) and in the nearby oil fields,
20 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

the Temblor Formation has for many years been 

divided informally by petroleum geologists into units 

or members given local names. These units are of 

little regional significance because they are thin, 

very lenticular, and in outcrop recognizable only in 

this part of the range. In the subsurface, however, 

they are economically very important because the 

sandstone units contain oil that is produced under 

favorable structural conditions, and the shale units 

form the caprocks. Mention is made of these units 

in articles on descriptions of the nearby oil fields, 

as well as in reports by Kleinpell (1938, p. 106, 

fig. 6) and Goudkoff (1943), and the units are 

described, with pertinent references by Foss and 

Blaisdell (1968, p. 33-43). These units, herein designated as members, are shown in table 2.

TABLE 2. Local stratigraphic units of the Temblor Formation in the Temblor Range between Chico Martinet Creek 

and Bitterwater Creek (fig. 9)

Stratigraphic unit

Thickness 

(ft)

Stages 

(Kleinpell, 1938)

Buttonbed Sandstone Member 

Media Shale Member _____.

Carneros Sandstone Member ___________

Santos Shale Member

and Agua Sandstone Member

as discontinous lenses as

thick as 48 ft within Santos

Shale Member.

Wygal ( =: "Phacoides") Sandstone Member. 

Cymric (="Salt Creek") Shale Member_.

0-800 

0-900

0-350 

0-450

Relizian.

Lower Relizian and

upper Saucesian. 

Saucesian. 

Lower Saucesian

and Zemorrian.

0-100 Lower Zemorrian. 

0-100 Zemorrian (?)

Anderson (1905, p. 169-170) originally described 

the "Temblor Beds" at "Canara Springs" (Carneros Spring in fig. 10) and at "Temblor." He never 

designated a type section, but Kleinpell (1938, p. 

107) and Curran (1943, p. 1364) considered the 

section at Carneros Creek described by Anderson to 

be the type locality of the Temblor Formation. Kleinpell (1938, p. 107), Woodring, Stewart, and Richards (1940, p. 130), and Curran (1943, p. 1369- 

1370) described the Temblor Formation exposed 

2 miles south in Zemorra Creek, a branch of Chico 

Martinez Creek (fig. 10), where the Temblor Formation is thicker and more completely exposed than 

at Carneros Creek.

It is here proposed that the type area of the 

Temblor Formation be designated as the exposures 

from Carneros Creek to Zemorra Creek, the type 

section as that exposed at Carneros Creek in sec. 32, 

T. 28 S., R. 20 E., and a reference section as that 

exposed at Zemorra Creek in sec. 9, T. 29 S., R. 20 

E. (figs. 9, 10). This type section is also the type 

section of some members of the Temblor Formation 

and the reference section for the others, as indicated in the following paragraphs. Part of this section is also the type section of the Zemorrian Stage

as defined by Kleinpell (1938, p. 106-108). The 

members of the Temblor Formation in the Chico 

Martinez Creek area (fig. 10) are herein defined in 

ascending order (thickness figures at Zemorra Creek 

as given by Woodring and others, 1940, p. 130).

The age of the Temblor Formation in its type 

area ranges from the early Zemorrian Stage, late 

Oligocene, through the Saucesian Stage, early Miocene, to the lowest part of the Relizian Stage, middle Miocene. This age range probably also applies 

to the Temblor Formation exposed in the southeastern Temblor Range and Devils Den. In areas 

west and northwest of the type area and at Reef 

Ridge, the Temblor Formation is mainly in the 

Saucesian Stage, early Miocene, and partly of Relizian age, middle Miocene.

CYMRIC SHALE MEMBER

The lowest shale member of the Temblor Formation is commonly known as the Salt Creek Shale 

(Williams, 1936; Goudkoff, 1943, pt. 2, p. 253, fig. 

99a; Curran, 1943, p. 1368-1369; Foss and Blaisdell, 1968, p. 40), but this name is preoccupied. This 

shale is herein renamed the Cymric Shale Member, 

for the nearby Cymric oil field (fig. 9). This member is disconformable on the Point of Rocks Sandstone and consists of dark-gray clayey to silty shale. 

It is traceable and recognizable in the outcrop only 

from Santos Creek southeastward to a point 3 miles 

southeast of Zemorra Creek (figs. 9, 11). The type 

section is in Zemorra Creek where this member is 

about 74 feet thick. Northeastward, downdip, it 

thickens to several hundred feet in the subsurface. 

It contains sparse foraminifers of the Zemorrian 

Stage, late Oligocene, and forms the lower part of 

the type Zemorrian Stage (of Kleinpell, 1938, p. 

103-108). Recent faunal studies by W. O. Addicott 

(oral commun., 1971) suggest, however, that the 

Cymric Shale Member may be at least in part in 

the Refugian Stage, early Oligocene. If this is so, 

this unit may be correlative with the Wagonwheel 

Formation near Devils Den. Nevertheless, to avoid 

complications, its age assignment to the early Zemorrian Stage is tentatively retained.

WYGAL SANDSTONE MEMBER

The lowest sandstone member of the Temblor 

Formation in the Chico Martinez Creek area is 

commonly known as the "Phacoides reef" (Kleinpell, 1938, p. 107; Goudkoff, 1943, pt. 2, p. 250; 

Curran, 1943, p. 1368) or "Phacoides Sand" (Foss 

and Blaisdell, 1968, p. 40). These names are not 

valid because they refer to a fossil rather than a 

locality. Therefore this sandstone is here renamed
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 21

Cameros Creek 

/.Jmdo /Tmg

,! : 42> ;.' .'.' .*

FORMATIONS AND MEMBERS LITHOLOGIC SYMBOLS

Pleisto-\Holo- [eerie cene 

F^l

1 

1 Miocene Oligocene 

§1

Qa

QTt

Te

Tmb

Tm

Tmd

Tmg

Ttb

Ttm

Ttc

Tts

Ttw

Tty

Tpr

Alluvium

Tulare Formation

Etchegoin Formation

Belridge Diatomite 

Member

McLure Shale 

Member

Devilwater Shale 

Member

Gould Shale Member

Buttonbed Sandstone 

Member

Media Shale Member

Carneros Sandstone 

Member

Santos Shale 

Member

Wygal Sandstone 

Member

Cymric Shale 

Member

Shale Monterey 

Temblor Formation

Point of Rocks 

Sandstone

i

or

ho:

UJ h0 ° °

 *

irS

TTJl-i

V++

Gravel

Sandstone

Clay shale

Siliceous shale

Cherty shale

Diatomite

FIGURE 10. Chico Martinez Creek area, Temblor Range, showing members of the Temblor Formation and Monterey Shale.

the Wygal Sandstone Member, for Wygal Spring 

(fig. 9). The type section is designated as that at 

Zemorra Creek, where this sandstone is about 75

feet thick and overlies the Cymric Shale Member. 

This sandstone is gray, and its upper part is glauconitic; locally a fossiliferous calcareous bed sev495-417 O - 73 - 4
22 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Formation lor 

a

!

CEDAR CREEK

AT MOUTH

E^EHE

In

CM

100' ^- 

2200'

123' [:: 

274'

-v- -/ 

- -/- 

_4^_ 

" '5 ' ' '

TWO MILES 

EAST OF MOUTH

r

f

m 

b

CM 

CO

VE

i es » 

1000'

200'

RTICA 

r500

-0

+- -tL SCA

FEET

 3

L

LE

M/

m

so

VPOLE 

3PRIN<

iles *| 

(Gc

4°; L 

300'

350'

100' t± 

100'

ON

Mo 

uld

- -/--

 z 

Z"

J~ :..... 

D::3:::

b?;:

Poi 

S

[ 

C

nte

'

y

nt 

ilic

)E 

RE

2n 

re 

3h

b

CO 

CO

VILWA1 

EK, 1 N 

WEST

niles H

y s

ale

350'

-160'-^ 

100'

80' 

180'

of

LI

ecus st

ER 

1ILE

hale 

Mem

?!!!!!

B;;;;

 2 

\\\-\-s\\\

-4&6- 

Rocks

THOL

iale

N 

Cl

c

ber

\

IE 

RE 

50

n

) 

o

Sar 

_OG

Argil

DIA 

EK, 1 

UTH 

i les180' 

300' 

120'

400'

idsto 

,IC

lacec

AC

L H 

Ef

-ft

-

 

ne 

c

IU

3UA 

^IILE 

kST

_4&6_

;YM

; shal«

 3

/

C/

rr

§

CM

BOL

3 S

\RNER 

CREEH

iles 

150' (::

500' 

150' ::

400'

50;' c

3d' =

-S

andsto

OS

::: 1::: 

2--

7v 

ne

S

\

Z 

n

un 

§

EMO 

CREE

niles240'

920'

230'

i6' 

195'

85' 

75'

RR 

EK

-» 

pJ

A

::; 1 :: 

_ 2 _

 .6 

S^-N^

__ _____ _

Formation jmblor 

MICROFAUNAL 

STAGES

Relizian

Saucesian

Zemorrian

Narizian

UJ 

C5

MIOCENE

IOLIGOCENE? | EOCENE 

FIGURE 11. Sections of the Temblor Formation from Cedar Creek to Zemorra Creek in the Temblor Range (fig. 9). Units 

as follows: (1) Buttonbed Sandstone Member, (2) Media Shale Member, (3) Carneros Sandstone Member, (4) upper 

part of Santos Shale Member, (5) Agua Sandstone Member, (6) lower part of the Santos Shale Member, (7) Wygal 

Sandstone Member, and (8) Cymric Shale Member. Thicknesses shown other than for Zemorra Creek are approximate.

eral feet thick occurs at or near the base. It is traceable south to Salt Creek and northwest to Media 

Agua Creek (figs. 9, 11). At both those places it 

laps over the Cymric Shale Member onto the Point 

of Rocks Sandstone. Northeastward, downdip from 

its outcrop, this member thickens to several hundred feet in the subsurface. It contains a molluscan 

fauna assigned an early "Vaqueros age," late Oligocene (W. 0. Addicott, oral commun., 1968), and the 

shale immediately above and that below is in the 

lower part of the type Zemorrian Stage (Kleinpell, 

1938, p. 103-108). Recent work on the fauna from 

this sandstone unit by Addicott (oral commun., 

1971) suggests, however, that this unit is somewhat 

older than the "Vaqueros Stage," but younger than 

the Refugian Stage. But to avoid complications, its 

assignment to the "Vaqueros Stage" is tentatively 

retained.

SANTOS SHALE AND AGUA SANDSTONE MEMBERS

The middle shale member of the Temblor Formation was named the Santos Shale by Gester and 

Galloway (1933) for Santos Creek, the type locality 

(fig. 9). This shale is medium to dark gray, clayey 

to silty, locally semisiliceous in the upper part, and

is conformable on the Wygal Sandstone Member. 

At Zemorra Creek, the reference section, this shale 

member is 295 feet thick and is divided into two 

parts, but the lower part, 180 feet thick, is separated from the upper part, about 60 feet thick, by 

the 35-foot-thick Agua Sandstone Member. The 

upper part of the Santos Shale Member is traceable 

northwestward to Cedar Creek, where it overlies the 

Agua Sandstone Member and the Point of Rocks 

Sandstone (fig. 11). Northeastward, downdip, the 

Santos Shale Member thickens in the subsurface, 

and the lower and upper parts are separated by the 

Agua Sandstone Member (Foss and Blaisdell, 1968, 

p. 39-40). The Santos Shale Member contains foraminifers diagnostic of the Zemorrian Stage, late 

Oligocene, in the lower part and of the Saucesian 

Stage, early Miocene, in the upper part (Kleinpell, 

1938, p. 105-108; Foss and Blaisdell, 1968, p. 40). 

At Zemorra Creek the lower part forms the upper 

part of the type Zemorrian Stage of Kleinpell 

(1938, p. 103-108), except the lowest 50 feet of that 

shale, which is assigned to the lower part of that 

stage (Foss and Blaisdell, 1968, p. 40).

The Agua Sandstone Member was named Agua 

Sandstone by Clark and Clark (1935, p. 137) for
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 23

Media Agua Creek (fig. 9). They did not designate 

a type locality, although they mentioned the outcrop at the mouth of Cedar Creek. This outcrop is 

designated the type locality as it was mapped by 

Heikkila and MacLeod (1951, pi. 1). This is the 

only other place besides Zemorra, Creek, the reference section, where this unit crops out, although at 

a few places between Cedar Creek and Zemorra 

Creek, the Santos Shale Member contains a sandstone bed a few feet thick that may be correlative. 

In the subsurface (in North Belridge, North and 

South Antelope Hills, McDonald Anticline oil fields 

and vicinity, (fig. 9) the Agua Sandstone Member 

is persistent, is several hundred feet thick, and is 

assigned to the top of the Zemorrian Stage (Foss 

and Blaisdell, 1968, p. 40).

The Agua Sandstone Member is light gray, arkosic, and locally pebbly. At the mouth of Cedar Creek 

it is as thick as 48 feet, occurs at the base of the 

Santos Shale Member, and is disconformable on the 

Point of Rocks Sandstone (fig. 11). At this outcrop 

it contains a few fossils, including Pecten magnolia, 

and is assigned a late "Vaqueros age" (W. 0. Addicott, oral commun., 1968). At Zemorra Creek this 

sandstone is 35 feet thick, is unfossiliferous, and is 

at the top of the type Zemorrian Stage (Kleinpell, 

1938, p. 103-108), late Oligocene.

CARNEROS SANDSTONE MEMBER

The name Carneros was first applied to the middle sandstone member of the Temblor Formation by 

Cunningham and Barbat (1932, p. 417-421) for 

Carneros Creek, the type locality (fig. 10). The Carneros Sandstone Member is conformable on the 

Santos Shale Member, is light gray and thick bedded, 

rarely contains fossils, and is about 215 feet thick 

at Zemorra Creek, the reference section, but as 

much as 500 feet thick in the area of figure 9. It is 

traceaible as far northwest as Cedar Creek (fig. 11). 

Northwest of Devilwater Creek the upper part 

intertongues into the lower part of the Media Shale 

Member, and the lowest sandstone tongue persists 

as a layer about 120 feet thick. Northeastward, 

downdip, the Carneros Sandstone Member thickens 

to more than 1,000 feet locally in the subsurface. 

It is within the Saucesian Stage, early Miocene, as 

indicated by foraminifers from the shales below 

and above.

MEDIA SHALE MEMBER

The name Media was first applied to the upper 

shale member of the Temblor Formation by Cunningham and Barbat (1932, p. 417-421), for Media 

Agua Creek (fig. 9). The Media Shale Member is

light gray, clayey to silty, and in part semisiliceous. 

It is conformable on the Carneros Sandstone Member, is 920 feet thick at Zemorra Creek, the designated type section (sec. 9, T. 29 S., R. 20 E., Carneros Rocks quadrangle), and about 500 feet thick 

at Carneros and Santos Creeks. It is traceable northwest to and beyond the mouth of Cedar Creek (figs. 

9, 11). Northwest of Devilwater Creek it thickens 

as the upper parts of the Carneros Sandstone Member and lower parts of the Buttonbed Sandstone 

Member intertongue into it. In the Cedar Creek area 

the Media Shale Member is as thick as 2,200 feet, 

and the upper part includes much hard semisiliceous 

shale.

In the Chico Martinez Creek area, the Media 

Shale Member contains foraminifers diagnostic of 

the upper Saucesian Stage, early Miocene; the uppermost 50 feet, a sandy siltstone, contains foraminifers 

diagnostic of the lower Relizian Stage, middle Miocene (Foss and Blaisdell, 1968, p. 39).

BUTTONBED SANDSTONE MEMBER

Anderson (1905, p. 170) referred to the top 

sandstone unit of his Temblor Beds at Carneros 

Creek as "button beds." This term has subsequently 

been commonly applied informally to this sandstone 

(Kleinpell, 1938, p. 105; Foss and Blaisdell, 1968, 

p. 38). The type locality was designated as Carneros 

Creek (Heikkila and MacLeod, 1951, p. 10), in sec. 

32, T. 28 S., R. 20 E. (fig. 10). It is here formally 

named the Buttonbed Sandstone Member for its 

exposure on Buttonbed Hill (fig. 10). This sandstone is light gray, thick bedded, and commonly calcareous, with numerous shell fragments. It ranges 

in thickness from 0 to 500 feet (240 ft thick at 

Zemorra Creek, the reference section). It is presumed to be locally disconformable on the Media 

Shale Member and may be a transgressive basal 

sandstone of the Monterey Shale, as indicated by 

an unconformity locally at its base in the Shale 

Hills area (Heikkila and MacLeod, 1951, p. 10) and 

at Devils Den. In other areas, this sandstone member or its equivalent is not differentiate from the 

underlying sandstone fades of the Temblor Formation.

The Buttonbed Sandstone Member is traceable 

northwestward from Zemorra Creek to and beyond 

Bitterwater Creek. Northwest of Devilwater Creek 

all but the upper part intertongues into the upper 

part of the Media Shale Member.

The Buttonbed Sandstone Member contains mollusks and buttonlike echinoids (mostly Scutella 

merriami) assigned to "Temblor age," Miocene, 

(W. 0. Addicott, oral commun., 1967). In the Chico
24 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Martinez Creek area, the Buttonbed Sandstone Member is in the early Relizian Stage (middle Miocene), 

as indicated by the microfauna in the adjacent shale 

below and above (R. L. Pierce, oral commun., 1968). 

At Devils Den, local names were applied to units 

within the Temblor Formation by Van Couvering 

and Alien (1943, p. 496-500) ; none of these are 

adopted herein. The members recognized in the 

Chico Martinez Creek area of the Temblor Range 

are believed to be as indicated in table 3, mainly on

TABLE 3. Members of the Temblor Formation exposed at 

Devils Den

Name applied by 

Van Couvering and

Alien (1943.)

Average (Members 1-5

Name of member thickness assigned to Hannah

(ft) Formation)

Buttonbed Sandstone Member __ ___ __

Media Shale Member __- _ __________ ____

Carneros Sandstone Member

(includes interbedded shale).

Upper part of Santos Shale Member _ _

Undivided lower members:

Agua Sandstone Member _

Lower part of Santos Shale Member _

Wygal Sandstone Member

Cymric Shale Member

50

350

200

300

180

100

70

50

Escudo Formation.

Member 1.

Member 2 (sandstone and shale).

Member 3 (shale).

Member 4 (sandstone).

Member 5 (shale).

Do.

Do.

the basis of similar lithologic sequences, although 

correlations are uncertain. In the northern exposures, the Buttonbed Sandstone Member overlaps 

the older members of the Temblor Formation.

MONTEREY SHALE 

REVIEW OF NOMENCLATURE

A distinctive marine deposit of predominantly 

siliceous organic shale, of early, middle, and late 

Miocene age, overlies the Vaqueros and Temblor 

Formations. In the Temblor Range and part of the 

Caliente Range, the name Monterey Shale was applied to this unit by Arnold and Johnson (1910, 

p. 55-62, pi. 1), who adopted the name from the 

term Monterey Formation applied by Blake (1856, 

p. 328-331) to a similar siliceous deposit exposed 

near Monterey.

Confusion resulted when part of this siliceous 

shale unit in the Diablo Range, Temblor Range, and 

Caliente Range was correlated with and assigned 

to the Santa Margarita Formation by Arnold and 

Anderson (1910) and English (1916, p. 202-203), 

and the name Maricopa Shale was applied to the 

rest of this shale unit in the Caliente Range by 

English (1916, p. 198-200, pi. XIX) and in the 

Temblor Range by Pack (1920, p. 35-41, pi. II). 

This was done when the terms Monterey Series (of 

Louderback, 1913, p. 191-214) and Monterey Group 

(of Lawson, 1914) were applied to most of the 

Miocene marine sedimentary rocks of the California 

Coast Ranges.

The terms Monterey Series and Maricopa Shale 

were discarded after 1935, and the term Monterey 

Shale was adopted for the lithologic unit of "predominantly hard silica-cemented shales and softer 

shales carrying siliceous microfossils" (Wilmarth, 

1938, p. 1407, 1299). The term Monterey Shale was 

applied to this unit by Woodring, Bramlette, and 

Kleinpell (1936, p. 127-146), Kleinpell (1938, p. 7, 

105; 122, fig. 6), Woodring, Stewart, and Richards 

(1940, p. 122-123), Hill, Carlson, and Dibblee (1958, 

p. 2988-2991), and Durham (1963, 1964, 1966). The 

term Monterey Formation was also applied (Simonson and Krueger, 1942, p. 1616; Bramlette and 

Daviess, 1944; Heikkila and MacLeod, 1951, p. 5, 11, 

pi. 1; Foss and Blaisdell, 1968, p. 36), but because 

this unit is characterized by a distinctive shale, the 

term Monterey Shale is hereby retained.

The Monterey Shale is the most extensive unit 

of the middle Tertiary sedimentary sequence on 

both sides of the San Andreas fault, in places extending beyond the limits of the Vaqueros and 

Temblor Formations. It was deposited under conditions of maximum inundation during the middle 

Tertiary sedimentary cycle.

STRATIGRAPHIC UNITS SOUTHWEST OF THE 

SAN ANDREAS FAULT

Southwest of the San Andreas fault, the Monterey Shale is from 2,000 to 3,000 feet thick on the 

southwest flank of the Caliente Range and the 

northeast flank of the La Panza Range, from which 

it extends northwestward under Salinas Valley. In 

the Caliente Range, Cuyama Valley, and Sierra 

Madre Mountains, the Monterey Shale intertongues 

northeastward into sandstone mapped as the Branch 

Canyon Sandstone (figs. 7, 12). In the La Panza 

Range and western Cuyama Valley, the Monterey 

Shale thins to only a few hundred feet; in places 

it wedges out.

The Monterey Shale exposed in the areas between 

the San Andreas and Rinconada faults is composed 

of two lithologic units: a lower unit of predominantly argillaceous shale of middle and locally in 

part of early Miocene age and an upper unit of 

siliceous shale of middle Miocene age. The lower 

unit has been named the Saltos Shale Member, and 

the upper unit the Whiterock Bluff Shale Member 

(fig. 7).

In several wells in the valley area between Atascadero and Shandon, the uppermost part (as much 

as 300 feet) of the Monterey Shale contains foraminifers diagnostic of the late Miocene Mohnian 

Stage (H. C. Wagner, oral commun., 1970). Part 

of the Monterey Shale exposed north of Atascadero
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 25

EXPLANATION

Buried

Contact 

Dotted where concealed

Fault

Dotted where concealed 

or inferred

Buried

Predominantly Branch Canyon 

Sandstone

Predominantly Caliente 

Formation

Buried

Predominantly Monterey 

Shale northeast of San 

Andreas fault, Santa 

Margarita Sandstone and 

Monterey Shale southwest of San Andreas 

fault

FIGURE 12. Probable original and present areal extent of contemporaneous formations or facies of mainly middle and

late Miocene age in southern Coast Ranges.

may also be of Late Miocene age. These are the 

only places within the area of figure 2 southwest of 

the San Andreas fault where the Monterey Shale is 

of late Miocene age. Monterey Shale of that age is

extensive in Salinas Valley, to the northwest.

SALTOS SHALE MEMBER

The Saltos Shale Member was named for Saltos 

Creek near the type locality (sees. 18, 19, and 20,
26 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

T. 11 N., R. 27 W., San Bernardino base line and 

meridian) in the central Caliente Range, 8-9 miles 

northwest of New Cuyama, by Hill, Carlson, and 

Dibblee (1958, p. 2989-2990), and the name is 

herein adopted. According to them, the member is 

about 2,150 feet thick at the type locality: the lower 

part, about 1,000 feet thick, is composed of gray 

clay shale and siltstone and is separated by a sill of 

basalt about 75 feet thick from the upper part, 

about 1,100 feet of soft fissile shale and hard, brittle 

siliceous shale and frequent thin beds of dolomite. 

The lower part was assigned to the Saucesian Stage, 

early Miocene, and the upper part to the Relizian 

Stage, middle Miocene.

The Saltos Shale Member exposed northwestward 

along the Caliente Range and in the La Panza 

Range is generally similar to that at the type locality, but in these places it lacks the basalt and averages about 1,500 feet in thickness. In the La Panza 

and northwestern Caliente Ranges, the Saltos Shale 

Member is composed of soft-weathering yellowishgray thin-bedded clayey to weakly siliceous or calcareous shale and contains a foraminiferal fauna 

of the Relizian Stage, middle Miocene. It conformably overlies the Painted Rock Sandstone Member 

of the Vaqueros Formation, in places with a gradational or intertonguing contact. In both these areas 

this shale unit is lithologically similar to and correlative with the Sandholdt Formation of Thorup 

(1943) in Salinas Valley.

Near the west end of Cuyama Valley, the lower 

150 feet of the Saltos Shale (?) Member is semisiliceous shale, and the upper 500 feet is clay shale 

that is overlain by the Branch Canyon (?) Sandstone. The shale there contains foraminifers assigned to the lower(?) Saucesian Stage (R. L. 

Pierce, oral commun., 1967). Where the Vaqueros 

Sandstone is missing, the shale overlies the Simmler 

Formation and underlying rocks of Paleocene(?) 

age with angular discordance of as much as 45°. 

This is the only place between the San Andreas and 

Rinconada faults where an angular unconformity 

appears within the middle Tertiary sedimentary 

sequence.

On the northeast flank of the Caliente Range, on 

both flanks southeast of Caliente Mountain, and in 

the eastern San Rafael Mountains, the Saltos Shale 

Member becomes mainly siltstone, in places containing sparse foraminifers of the Saucesian and Relizian Stages, and thin sandstone beds that contain 

mollusks of the "Temblor Stage" (Vedder and 

Repenning, 1965). Included in the Saltos Shale Member of these exposures is several hundred feet of 

similar but stratigraphically higher siltstone that

contains foraminifers of the Luisian Stage and that 

grades laterally westward into the Whiterock Bluff 

Shale Member (fig. 7). The siltstone of the Saltos 

Shale Member intertongues northeastward into 

the Branch Canyon Sandstone within a few miles 

of the San Andreas fault (fig. 12).

WHITEROCK BLUFF SHALE MEMBER

In the Caliente Range, La Panza Range, and 

Sierra Madre Mountains, the siliceous shale unit 

was named the Whiterock Bluff Shale Member of 

the Santa Margarita Formation by English (1916, 

p. 191-215, pi. XIX). This shale unit was named 

for Whiterock Bluff, the type locality (sec. 25, T. 

11 N., R. 28 W.), about 8 miles west-northwest of 

New Cuyama (fig. 1), where this shale is approximately 1,200 feet thick. This name was adopted and 

applied to this shale unit by Hill, Carlson, and Dibblee (1958, p. 2990-2991), but the unit was reassigned to the Monterey Shale. The Whiterock Bluff 

Shale Member was reported by them to contain 

foraminifers diagnostic of late Relizian and Luisian 

Stages, middle Miocene. This name as used by Hill, 

Carlson, and Dibblee (1958) is adopted herein for 

this shale unit in the area between the San Andreas 

and Rinconada faults.

The Whiterock Bluff Shale Member consists of 

hard, brittle thin-bedded siliceous shale and interbedded fissile to punky shale. It is as much as 1,500 

feet thick, but averages 1,200 feet. It is gradational 

downward into the Saltos Shale Member and upward into sandstone of the Santa Margarita Formation. For about 6 miles on each side of Indian Creek 

(about 12 miles south of Shandon, fig. 2), a zone 

about 70 feet thick near the top of the Whiterock 

Bluff Shale Member contains thin layers of phosphatic pellets and bentonite (H. D. Gower, oral 

commun., 1970). This zone is overlain by about 80 

feet of siliceous and diatomaceous shale, which is 

overlain by the Santa Margarita Formation. In 

western Cuyama Valley and on the southwest flank 

of the La Panza Range, the Whiterock Bluff Shale 

Member is absent or may be represented by sandstone. Elsewhere this shale unit is widely distributed, and in Salinas Valley this member and the 

underlying Saltos Shale Member are recognizable 

in well logs as far northeast as San Juan Creek. It 

is noteworthy, however, that within 7-10 miles of 

the San Andreas fault, as in the Caliente Range, 

this siliceous shale unit grades laterally northeastward through siltstone of the Saltos Shale Member 

lithology into the Branch Canyon Sandstone (figs. 

7,12).

In many places the Whiterock Bluff Shale Mem-
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 27

her contains abundant calcareous foraminifers. 

These are diagnostic of the Luisian Stage, middle 

Miocene. The exposure of the Whiterock Bluff Shale 

Member in sec. 21, T. 28 S., R. 14 E., 12 miles east 

of Atascadero (fig. 2) is the type locality of the 

Luisian Stage, as defined by Kleinpell (1938, p. 121- 

123). In the Indian Creek area, the phosphatic pellet 

zone near the top of the member and 30 feet of the 

overlying shale also contain foraminifers of the 

Luisian Stage (H. D. Gower, oral commun., 1970). 

At the type locality of the Whiterock Bluff Shale 

Member in Cuyama Valley, this member is mainly 

in the Luisian Stage, but the lowest part is in the 

upper Relizian Stage (Hill and others, 1958, p. 

2991), middle Miocene.

STRATIGRAPHIC UNITS NORTHEAST OF THE 

SAN ANDREAS FAULT

Northeast of the San Andreas fault, the Monterey Shale conformably overlies the Temblor Formation and is about 7,200 feet thick in the southeastern and central parts of the Temblor Range. 

Northwestward, it thins to about 2,600 feet in the 

Diablo Range north of Cholame and to only 600 feet 

on Reef Ridge and northwest of McLure Valley. 

The Monterey Shale may be divided regionally into 

two parts: a lower division mainly of middle Miocene age and an upper division mainly of late Miocene age.

The only place northeast of the San Andreas 

fault where a complete section of the Monterey 

Shale is continuously exposed in a homoclinal structure is along Chico Martinez Creek in the Temblor 

Range (fig. 10). This section is the upward continuation of the Zemorra Creek section of the underlying Temblor Formation. Therefore this section is 

designated as the reference section for the Monterey Shale and its members, as well as for the 

Temblor Formation, northeast of the San Andreas 

fault. This section of the Monterey Shale was described by Woodring, Stewart, and Richards (1940, 

p. 125), who measured and divided it into 11 numbered units.

In the southeastern and central parts of the Temblor Range, the lower division of the Monterey 

Shale is 2,000-3,000 feet thick and is composed 

mostly of siliceous shale that is not lithologically 

differentiable. On the northeast flank of the central 

part of the Temblor Range, this division is about 

1,300 feet thick: the lower part is siliceous shale 

that is locally known as the Gould Shale Member, 

and the upper part is argillaceous shale that is 

locally known as the Devilwater Shale Member. In 

the northwestern Temblor Range, southwest foothills of the Diablo Range, and in Devils Den area, 

the lower division of the Monterey Shale is about 

1,000 feet thick and is locally absent; it is composed only of argillaceous shale. In the McLure 

Valley-Reef Ridge area, the lower division is largely 

absent.

Because at their type localities at Chico Martinez Creek in the central Temblor Range the Gould 

Shale Member is a siliceous shale unit and the 

Devilwater Shale Member is an argillaceous shale 

unit, the name Gould Shale Member is here adopted 

and applied throughout the Temblor Range to the 

part of the lower division of the Monterey Shale 

that is mainly siliceous shale and is within the Relizian and Luisian Stages, middle Miocene (and in one 

place late Saucesian Stage); the name Devilwater 

Shale Member is adopted and applied to the part 

that is mainly argillaceous shale and is within the 

Luisian Stage, middle Miocene age, in the Temblor 

Range and southeastern Diablo Range. These names 

are thereby applied to lithologic rather than paleontologic units.

Southwest of the Recruit Pass fault in the southeastern Temblor Range, the lower division of the 

Monterey Shale is composed of semisiliceous shale, 

similar to that of the Gould Shale Member, and 

about 50 percent of intenbedded sandstone.

The upper division of the Monterey Shale is a 

unit of thin-bedded siliceous shale and (or) siliceous 

mudstone throughout the region northeast of the 

San Andreas fault. In the southeastern and central 

parts of the Temblor Range, it is 4,000-5,000 feet 

thick. Northwestward it thins to about 1,900 feet 

in the Diablo Range north of Cholame and to only 

550 feet in the McLure Valley-Reef Ridge area. 

Unfortunately this shale unit has a complex and 

confused terminology because its identity as a 

single lithologic unit throughout this region has not 

been recognized.

In the Diablo Range and parts of the Temblor 

Range, the upper division of the Monterey Shale 

was originally referred to the Monterey Shale by 

Anderson (1905, p. 171, pi. 34), but a few years 

later it was assigned to the Santa Margarita Formation by Arnold and Anderson (1908, p. 35-39, 

pi. 1), Arnold and Johnson (1910, p. 63-72), and 

English (1918, p. 229-230, pi. 2) when that name 

was applied to all strata of late Miocene age in the 

Coast Ranges, regardless of their lithology. Still 

later, this siliceous shale unit in the Diablo Range 

was named McLure Shale by Henny (1930, p. 403- 

410) because he thought that the sandstone that 

locally unconformably underlies it 14 miles west of
28 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Coalinga (NW^4 sec. 17, T. 21 S., R. 13 E.) was the | 

Santa Margarita Sandstone on the basis of fossils. 

That sandstone is now known to be the Temblor. 

Since then, the name McLure has been so much 

used for this shale unit that it was adopted by 

Woodring, Stewart, and Richards (1940, p. 114, 

122-125) and Stewart (1946, p. 103-104, pi. 9), 

and they designated this unit as a member of the 

Monterey Shale. In the southern part of the Diablo 

Range, this shale unit was referred to the McLure 

Shale by Marsh (1960, p. 32-33, pi. 1) and to the 

Monterey Formation by Dickinson (1966a, p. 713, 

fig. 4, pi. 2; 1966b, pi. 1).

In the Chico Martinez Creek area of the Temblor 

Range, the upper division of the Monterey Shale 

was for many years informally divided by petroleum 

geologists into two local stratigraphic units or members. The lower unit was called McDonald Shale 

(Cushman and Goudkoff, 1938, pi. 1) or McDonald 

Shale Member of Monterey Formation (Simonson 

and Krueger, 1942, p. 1616-1617; Foss and Blaisdell, 1968, p. 37), presumably for the McDonald 

anticline oil field. This unit presumably corresponds 

to Monterey Shale units 4 and 5 (total thickness 

1,105 ft) of Woodring, Stewart, and Richards (1940, 

p. 125) and contains foraminifers diagnostic of the 

early Mohnian Stage. The upper unit was called 

Antelope Shale (Noble, 1940, p. 1332, fig. 1) or 

Antelope Shale Member of Monterey Shale (Simonson and Krueger, 1942, p. 1611, 1617, fig. 2; Foss 

and Blaisdell, 1968, p. 37), presumably for Antelope 

Valley. This unit probably corresponds to Monterey 

Shale units 6-9 (total thickness 3,815 ft) of Woodring, Stewart, and Richards (1940, p. 125) and 

contains diatom remains and sparse foraminifers 

assigned to the late Mohnian Stage. The McDonald 

and Antelope units are composed of siliceous shale 

and are thus difficult to distinguish. In the adjacent 

subsurface area they are recognized on the basis of 

paleontology and electric log correlations.

In the Shale Hills area of the northwestern Temblor Range (about 8 miles south of Devils Den), the 

upper division of the Monterey Shale was referred 

to the McDonald Shale Member by Heikkila and 

MacLeod (1951, p. 13-14, pi. 1). In the central and 

southeastern parts of the Temblor Range, this division was mapped informally as the AntelopeMcDonald Shale Member by Simonson and Krueger 

(1942, p. 1611, 1617) and Dibblee (1962, 1968).

The application of four names to the siliceous 

shale of the upper division of the Monterey Shale 

or parts of it is the source of much confusion. It 

was found impractical to differentiate this shale unit 

in the field, especially where it is complexly folded.

Therefore it is appropriate to eliminate all but one 

name. Santa Margarita has been eliminated for this 

unit because this name is no longer applied to a 

shale unit. The names McDonald and Antelope, 

widely used in the subsurface but mainly as paleontologic units, are preoccupied and therefore not 

adopted. The usage of the term McLure Shale Member of the Monterey Shale by Woodring, Stewart, 

and Richards (1940, p. 114, 122-125) and Stewart 

(1946, p. 303-304) is adopted herein for the siliceous shale unit of mainly late Miocene age of the 

Monterey Shale throughout the entire region northeast of the San Andreas fault.

The lithologically distinct members or units of 

the Monterey Shale northeast of the San Andreas 

fault recognized on the basis of lithology are shown 

in figure 10 and discussed in the following sections.

GOULD SHALE MEMBER

The siliceous shale that forms the lowest unit of 

the Monterey Shale exposed at Chico Martinez Creek 

was named the Gould Shale Member of the Temblor 

Formation by Cunningham and Barfoat (1932, p. 

418) for nearby Gould Hill (fig. 10). They designated the type locality as the area between the exposure along that creek and 2 miles southeastward 

(fig. 10). This name was adopted as a member of 

the Monterey Shale by Woodring, Bramlette, and 

Kleinpell (1936, p. 127-146), Woodring, Stewart, 

and Richards (1940, p. 125), Heikkila and MacLeod 

(1951, p. 11-12), and Foss and Blaisdell (1968, 

p. 38).

The Gould Shale Member is composed of tanweathering thin-bedded brittle siliceous shale alternating with softer fissile shale. It conformably overlies the Buttonbed Sandstone Member of the Temblor Formation and is overlain by the Devilwater 

Shale Member of the Monterey Shale. At the type 

locality, the Gould Shale Member is 285 feet thick 

(Woodring and others, 1940, p. 125), but to the 

northwest it is as thick as 600 feet. From the type 

locality, it is traceable northwestward for about 

20 miles and then disappears, never to reappear.

In all these exposures, the Gould Shale Member 

contains foraminifers diagnostic of the Relizian 

Stage, middle Miocene (Kleinpell, 1938, fig. 14; 

Foss and Blaisdell, 1968, p. 38).

In the southeastern part of the Temblor Range 

and southwest flank of the central part, all the 

lower division, or middle Miocene part, of the Monterey Shale is composed of siliceous shale lithologically similar to the Gould Shale Member of the Chico 

Martinez Creek area. All this siliceous shale is 

therefore assigned to the Gould Shale Member on 

the basis of lithologic similarity, even though the
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 29

upper part is presumably correlative in age with 

the Devilwater Shale Member of the Chico Martinez Creek area (fig. 10). In the southeastern Temblor Range, this siliceous shale unit was informally 

called Devilwater-Gould member of the Monterey 

(Simonson and Krueger, 1942, p. 1611, 1616, 1626- 

1627; Dibblee, 1962, 1968). This unit, now designated as the Gould Shale Member, is from 2,000 to 

3,000 feet thick; it conformably overlies clay shale 

of the Temblor Formation and is overlain by the 

McLure Shale Member of the Monterey Shale. In 

these exposures, the Gould Shale Member contains 

foraminifers diagnostic of the Relizian Stage in the 

lower part and Luisian Stage, middle Miocene, in 

the upper part. In one place in the extreme southeastern Temblor Range, however, the lowest strata 

of this siliceous shale unit contain foraminifers 

diagnostic of the late Saucesian Stage, early Miocene (R. L. Pierce, oral commun., 1967).

DEVILWATER SHALE MEMBER

The argillaceous shale that forms the upper part 

of the lower division of the Monterey Shale in the 

northwestern Temblor Range is locally known as 

the "Devilwater Silt" (Bailey, 1939, p. 317; Heikkila 

and MacLeod, 1951, p. 11-12, pi. 1; Foss and Blaisdell, 1968, p. 38). It is presumably named for Devilwater Creek (fig. 9). This name is adopted herein 

because of its long established usage but is modified to Devilwater Shale Member because it is not 

"silt" (an unconsolidated sediment) but is clayey 

shale with lesser amounts of siltstone and finegrained sandstone. The type section is here designated as the section exposed at Chico Martinez 

Creek, where it is composed of 1,190 feet of soft 

clayey shale, locally containing abundant foraminifers, and silty mudstone (Monterey Shale units 3 

and 4 of Woodring and others, 1940, p. 125) separating the Gould Shale Member below from the 

McLure Shale Member above (fig. 10).

The Devilwater Shale Member is about 1,000 

feet thick in most exposures. It persists northwest 

of Packwood Creek into the southwest foothills of 

the Diablo Range east of Cholame Valley, where it 

was mapped as the upper Temblor Sandstone by 

Marsh (1960, pi. 1) and as the oiltstone member of 

the Vaqueros-Temblor Formation by Dickinson 

(1966a, p. 711-713, pi. 2). The Devilwater Shale 

Member is also present in the Devils Den area, 

where it is about 700 feet thick. There it was called 

Alferitz Formation and assigned to the Luisian 

Stage, middle Miocene, by Van Couvering and Alien 

(1943, p. 496-500), but the name Alferitz is not 

adopted.

In the Temblor Range the Devilwater Shale Member contains foraminifers diagnostic of the middle 

Miocene Luisian Stage (Foss and Blaisdell, 1968, 

p. 38). It is presumably of the same age in the 

Diablo Range. In the subsurface of the Kettleman 

Hills, it and the correlative of the Gould Shale Member are represented mostly by sandstone which 

there was assigned to the Temblor Formation by 

Woodring, Stewart, and Richards (1940, fig. 8).

INTERBEDDED SHALE AND SANDSTONE MEMBER

On the southwest slope of the southeastern part 

of the Temblor Range and southwest of the Recruit 

Pass fault, the conglomerate of the Santa Margarita Formation is unconformably underlain by Monterey Shale of which as much as 1,500 feet is exposed although the base is buried. The shale is 

semisiliceous and contains about 50 percent interbedded light-gray sandstone. The shale contains 

foraminifers diagnostic of the Relizian and Luisian 

Stages, middle Miocene (Vedder, 1970), and is 

therefore correlative with the Gould Shale Member 

east of the Recruit Pass fault.

M'LURE SHALE MEMBER

The McLure Shale Member is composed of whiteweathering dark-brown thin-bedded chalky to hard 

porcelaneous siliceous shale. The type locality, designated by Henny (1930, p. 404, table 1), is in sec. 

8 (not sec. 6), T. 24 S., R. 17 E., on the west side 

of McLure Valley, for which it was named. At that 

locality, this shale is 800 feet thick and is unconformable on the Panoche Formation. In the McLure 

Valley and Reef Ridge areas, this member ranges 

from 550 to 1,000 feet in thickness, thinning northward, and is unconformable on the Temblor and 

older formations. In the Reef Ridge area the McLure 

Shale Member locally contains a basal conglomerate 

and sandstone with serpentine clasts (Stewart, 1946, 

p. 98, 103-104; Adegoke, 1969, p. 20). On the 

southwest flank of the Diablo Range and in the 

northwestern part of the Temblor Range, the McLure Shale Member thickens southeastward to about 

5,000 feet and is conformable on the Devilwater 

Shale Member or unconformable on the Point of 

Rocks Sandstone or Panoche Formation where the 

Devilwater Shale Member and Temblor Formation 

are absent. In these areas the McLure Shale Member contains one or more lenses of sandstone (Polonio Sandstone Tongue in McLure Shale of Marsh, 

1960, p. 32-33).

The reference section of the McLure Shale Member of the Monterey Shale is here designated at 

Chico Martinez Creek in sees. 10 and 11, T. 29 S., 

R. 20 E. (fig. 10), where it is completely exposed.
30 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

There it conformably overlies the Devilwater Shale 

Member and grades upward into the Belridge Diatomite Member. In this section the McLure Shale 

Member is 4,930 feet thick and corresponds to Monterey Shale units 4-9 of Woodring, Stewart, and 

Richards (1940, p. 125). This siliceous shale member includes units informally called McDonald Shale, 

Antelope Shale, and Chico Martinez Chert Members 

(San Joaquin Geological Society, 1959, p. 13; Foss 

and Blaisdell, 1968, p. 37; Elliot and others (1968, 

p. 110-112). These terms are not adopted because 

all these units are composed of siliceous shale, and 

outside the Chico Martinez Creek area it is not possible to differentiate them on a lithologic basis with 

certainty on the surface. The lowest unit, the McDonald of local usage, is recognizable in the Elk 

Hills and other oil fields on the basis of electric log 

patterns and early Mohnian foraminifers (J. C. 

Maher, oral commun., 1970).

In the southeastern part of the Temblor Range, 

the McLure Shale Member is from 3,000 to 5,000 

feet thick and grades upward into the Belridge 

Diatomite Member. It overlies similar siliceous 

shale of the Gould Shale Member from which it is 

differentiated mainly by a color change; the McLure 

Shale Member weathers white, whereas the Gould 

Shale Member weathers cream to buff and is somewhat less siliceous and more fissile. Near Taft and 

Maricopa, the McLure Shale Member contains several lenses of sandstone.

The McLure Shale Member contains much diatom 

debris, arenaceous foraminifers, and fish scales. It 

also contains sparse calcareous foraminifers diagnostic of the Mohnian Stage, late Miocene (R. L. 

Pierce, oral commun., 1968). Only in the extreme 

southeastern part of the Temblor Range do the 

lowest beds contain foraminifers of the middle Miocene Luisian Stage (Vedder, 1970).

BELRIDGE DIATOMITE MEMBER

The Belridge Diatomite Member, designated herein as the uppermost member of the Monterey Shale, 

was named informally by Siegfus (1939, p. 29) and 

Young (1943, p. 523-524) for the South Belridge 

oil field (fig. 9). The type section is herein designated as the section exposed near the mouth of 

Chico Martinez Creek (SEi/4 sec. 2, T 29 S., R 20 

E., fig. 10). This member corresponds to Monterey 

Shale units 10 and 11 (total exposed thickness 830 

ft) of Woodring, Stewart, and Richards (1940, p. 

125). It is composed of white-weathering soft fissile 

to punky diatomite that grades downward into the 

McLure Shale Member and is overlain unconformably by the Tulare Formation. At Bacon Hills, 2

miles north of the type section, and near Gould Hill, 

2 miles southeast, this diatomite unit is overlain 

disconformably by the Etchegoin Formation.

In the foothills of the Temblor Range from McKittrick to Maricopa, the Belridge Diatomite Member is discontinuously exposed and is similar to the 

Belridge at Chico Martinez Creek. Just west of Taft, 

as much as 2,200 feet of this unit is exposed unconformably below the Tulare Formation.

The Belridge Diatomite Member has been correlated with the Reef Ridge Shale and assigned a 

Miocene and Pliocene age by Foss and Blaisdell 

(1968, p. 36-37). It is, however, lithologically unlike the Reef Ridge Shale near Reef Ridge. In the 

exposed sections, the Belridge Diatomite Member 

contains foraminifers and fish scales diagnostic only 

of the late Mohnian Stage, late Miocene (R. L. 

Pierce, oral commun., 1967).

From field relations the Belridge Diatomite Member is considered to be older than the type Reef 

Ridge Shale because in the extreme southeastern 

Temblor Range the Santa Margarita Formation, 

which intertongues into the Belridge Diatomite 

Member, is overlain by the Bitterwater Creek Shale, 

which in turn is probably correlative with the type 

Reef Ridge Shale. If this is so, then the Belridge 

Diatomite Member may be correlative with the 

upper part of the McLure Shale Member of the 

McLure Valley-Reef Ridge area.

The relationship of the Belridge Diatomite Member exposed in the Temblor Range to the unexposed 

Reef Ridge Shale in the oil fields to the east is uncertain because the exposed Belridge Diatomite 

Member has not definitely been recognized in the 

oil field subsurface area. These units have been correlated on the basis pf supposed similar stratigraphic 

position (Foss and Blaisdell, 1968, p. 36), even 

though they are different lithologically. Subsurface 

structural data suggest that the Belridge Diatomite 

Member correlates wtih the upper part (the Antelope Shale of drillers) of the McLure Shale Member in the subsurface and dips under the subsurface 

argillaceous(?) unit referred to the Reef Ridge 

Shale (H. C. Wagner, oral commun., 1970). If this 

is correct, the exposed Belridge Diatomite Member 

is older than the Reef Ridge Shale of the subsurface.

Because of the foregoing evidence, the Belridge 

Diatomite Member exposed in the Temblor Range 

is assigned to the late Mohnian Stage, late Miocene, 

and is considered to be older than the Reef Ridge 

Shale.

BRANCH CANYON SANDSTONE

Marine sandstone that grades laterally westward 

into the Monterey Shale in the Sierra Madre Moun-
MIDDLE TERTIARY SEDIMENTARY SEQUENCE 31

tains and Caliente Range (fig. 7) was named the 

Branch Canyon Formation by Hill, Carlson, and 

Dibblee (1958, p. 2991-2993) for Branch Canyon 

(3 miles south of New Cuyama), the type section 

(sec. 2. T. 9 N., R. 27 W.). This usage is adopted 

herein but the name is modified to Branch Canyon 

Sandstone.

In the Branch Canyon area south of Cuyama 

Valley, the Branch Canyon Sandstone is about 

3,200 feet thick. The lower 2,100 feet ("Vaqueros," 

"Temblor," and "Briones," of Eaton and others, 

1941, fig. 13) contains mollusks and echinoids diagnostic of the "Temblor Stage," middle Miocene. The 

upper 1,100 feet ("upper Briones," "Cierbo," and 

"lower Neroly" of Eaton and others, 1941, fig. 13) 

contains mollusks and echinoids diagnostic of the 

"Santa Margarita Stage," late Miocene, and is overlain by the Santa Margarita Formation. Farther 

east, the Branch Canyon Sandstone is overlapped 

by and tongues out into nonmarine formations.

In the Caliente Range, the Branch Canyon Sandstone is as much as 3,000 feet thick. There it contains mollusks of the "Temblor Stage," middle Miocene, only. It intertongues southwestward into the 

Saltos Shale Member of the Monterey Shale in both 

northwestern and southeastern parts of the range. 

In the southeastern part, it is overlain by and 

tongues laterally eastward into the Caliente Formation.

Several wells drilled for petroleum in the western 

parts of the Carrizo Plain and near the San Juan 

River to the northwest and a well northwest of 

Cholame penetrated sandstone of, or correlative 

with, the Branch Canyon Sandstone. These occurrences and the exposures of this sandstone along 

the northeastern flank of the Caliente Range suggest that the Branch Canyon Sandstone may be continuous under the southwestern part of the Carrizo 

Plain to and beyond Cholame. Along this strip, this 

marine sandstone intertongues southwestward into 

the Monterey Shale and northeastward toward the 

San Andreas fault into the Caliente Formation (fig. 

12). Similar conditions prevail in the eastern Sierra 

Madre Mountains and presumably under Cuyama 

Valley. These relations indicate that the Branch 

Canyon Sandstone is essentially a strandline deposit 

between the Monterey Shale deposited offshore to 

the southwest and the terrestrial Caliente Formation to the northeast.

SANTA MARGARITA FORMATION 

Throughout much of the region southwest of the 

San Andreas fault, the Monterey Shale is overlain 

by marine sandstone that was named the Santa

Margarita Formation by Fairbanks (1904) for exposures at Santa Margarita, the type locality (8 

miles southeast of Atascadero, fig. 2). This usage 

is herein retained for this sandstone unit.

The Santa Margarita Formation is about 1,500 

feet thick in most places and is composed mainly of 

white friable sandstone. In some places, such as 

north of the La Panza Range and also south of 

Cuyama Valley, it contains thin rhyolitic tuffaceous 

beds, zones of phosphatic pellets, and one or two 

thin units of silty diatomaceous siliceous shale. 

South of Cuyama Valley the Santa Margarita Formation is underlain by upper Miocene beds of the 

Branch Canyon Sandstone, from which it is arbitrarily separated by a shale unit at the base of the 

Santa Margarita Formation. In one exposure just 

west of Carrizo Plain, the Santa Margarita Formation tongues eastward into nonmarine red beds. 

Within a few miles of the San Andreas fault in the 

southeastern Caliente Range and under Carrizo 

Plain, the Santa, Margarita Formation is not present, but is probably represented by the upper part 

of the Caliente Formation.

The sandstone of the Santa Margarita Formation 

contains shallow-water marine mollusks and echinoids of the "Santa Margarita Stage," late Miocene. 

It was deposited as a littoral marine facies of a 

regressing sea.

Northeast of the San Andreas fault, coarse clastic 

deposits in the upper Miocene section are present 

only in the southeastern part of the Temblor Range. 

In this area very coarse conglomerate, which locally 

contains mollusks of late Miocene age, was referred 

to the Santa Margarita Formation by Simonson and 

Krueger (1942 p. 1619-1621). This usage is retained herein. This conglomerate, which also includes lenses of breccia and sandstone, is as much as 

2,500 feet thick. It intertongues northeastward, 

downdip, into the Belridge Diatomite Member of 

the Monterey Shale.

CALIENTE FORMATION

In areas southwest of the San Andreas fault, 

terrestrial deposits that intertongue westward into 

the marine deposits of Miocene age (fig. 7) were 

named the Caliente Formation by Hill, Carlson, and 

Dibblee, 1958 p. 2993-2995) for the Caliente Range. 

The type locality was designated in the southeastern 

part of the range in sees. 26 and 23, T. 11 N., R. 26 

W., 5-6 miles northeast of New Cuyama. This usage 

is adopted herein.

The Caliente Formation of the Caliente Range is 

as thick as 4,200 feet and consists of varicolored 

sandstone, claystone, conglomerate, and four units
32 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

of basalt. It has yielded vertebrate remains diagnostic of the following ages of the mammalian 

chronology (fig. 4): Arikareean, late Oligocene (?) 

and early Miocene; Hemingfordian, middle Miocene; Barstovian, middle (?) and late Miocene; 

Clarendonian, late Miocene (?); and Hemphillian, 

Pliocene (Repenning and Vedder, 1961; Vedder and 

Repenning, 1965). It is therefore assigned an Oligocene (?), Miocene, and Pliocene age (fig. 7), but it 

is mostly of Miocene age.

The strata of the Caliente Formation that contain 

mammalian faunas assigned to the Arikareean, 

Hemingfordian, and early Barstovian ages intertongue westward into marine beds that have yielded 

molluscan faunas diagnostic of the "Temblor Stage" 

and foraminiferal faunas diagnostic of the Saucesian, Relizian, and Luisian Stages in the central 

Caliente Range. The strata that contain mammalian 

faunas assigned to the late Barstovian, Clarendonian, and Hemphillian "ages" are overlain by the 

Quatal Formation and are considered in part if not 

in whole correlative with the Santa Margarita Formation, which is also overlain by the Quatal Formation south of Cuyama Valley and northwest of Carrizo Plain. If all the upper strata of the Caliente 

Formation correlate with the Santa Margarita 

Formation, then the Santa Margarita, of late Miocene age of the marine invertebrate chronology, 

may be in part Pliocene of the mammalian chronology. Until the relationship of the mammalian 

"ages" to the marine "ages" and stages is more 

precisely known, this problem is unresolved.

In the Santa Barbara Canyon area southeast of 

Cuyama Valley, red beds that underlie the Branch 

Canyon Sandstone were named the Pato Red Member of the Vaqueros Formation by English (1916, 

p. 200, pi. XIX), but assigned to the Caliente Formation (by Hill, Carlson, and Dibblee (1958, p. 2995). 

The latter usage is retained, and the name Pato is 

considered obsolete. These beds contain sparse mammalian remains that suggest Arikareean age (J. G. 

Vedder, oral commun., 1968).

In the Red Hills northwest of Carrizo Plain, the 

granitic basement is overlain by about 3,000 feet of 

red to gray coarse boulder-cobble conglomerate of 

granitic detritus. This conglomerate is questionably 

referred to the Caliente Formation and is presumably of middle or late Miocene age, but it may be 

in part of early Miocene or Oligocene (?) age. It is 

overlain by sandstone that has late Miocene fossils 

and is assigned to the Santa Margarita Formation 

but that could be correlative with the Branch 

Canyon Sandstone.

A well drilled for petroleum about 2 miles east

of the Red Hills penetrated terrestrial beds of the 

Caliente (?) Formation to a depth of 2,910 feet, 

then struck granitic basement. Another well about 

11 miles northwest of the Red Hills or 2V& miles 

northwest of Cholame was drilled through terrestrial sedimentary rocks, presumably of the Caliente 

Formation, similar to those in the Red Hills from 

depths of 1,950 to 6,523 feet, then entered granitic 

basement.

About 18 miles southeast of the Red Hills, red 

sandy beds which intertongue(?) southwestward 

into the Santa Margarita Formation crop out.

The widely scattered exposures of the Caliente 

Formation are probably only a very small part of 

its total areal extent; it is largely covered by 

younger formations. This terrestrial unit or facies 

probably underlies the southeastern part of Cuyama 

Valley and possibly much of the northeast margin 

of Carrizo Plain (fig. 12), as suggested by the distribution of the formation in surface exposures and 

well sections referred to. If the Caliente Formation 

is continuous along this strip, it intertongues southwestward into the Branch Canyon Sandstone and 

was deposited along a coastal plain adjacent to the 

Miocene sea to the southwest. The position of the 

west margin of the continental facies southwest of 

the San Andreas fault is about as postulated by 

Hill and Dibblee (1953, p. 446-448) but extends 

farther northwest. The granitic detritus that makes 

up the Caliente Formation was derived from a 

granitic terrane that presumably lay northeast of 

the San Andreas fault in middle Tertiary time.

BASALT

Exposures of volcanic flows, sills, and dikes of 

olivine basalt are present only in the middle Tertiary 

sedimentary sequence in the Caliente Range and on 

the east margin of the La Panza Range (fig. 7). 

Most of the flows are in the Monterey Shale, Branch 

Canyon Sandstone, and middle and upper Miocene 

parts of the Caliente Formation of the Caliente 

Range. Dikes are locally abundant in the Vaqueros 

and Simmler Formations near Soda Lake, and several sills occur in the Vaqueros Formation.

In the southeastern Caliente Range, two of three 

prominent basalt flows ("Triple basalts" of Eaton, 

1939; Hill and others, 1958, p. 2994; and Vedder 

and Repenning, 1965) were radiometrically dated 

by Turner (1970, p. 115): the upper flow was dated 

as about 14.2 and 14.4 million years, and the lower 

one as about 16.1 million years. Both flows are in 

the Branch Canyon Sandstone, which contains a 

"Temblor" fauna and which intertongues eastward
UPPER TERTIARY SEDIMENTARY SEQUENCE 33

into the part of the Caliente Formation that contains a "Barstovian" fauna.

BITTERWATER CREEK SHALE

Marine siliceous shale or mudstone that disconformablyC?) overlies conglomerate of the Santa 

Margarita Formation in the Elkhorn Hills area 

southwest of Maricopa on the northeast side of the 

San Andreas fault was named the Bitterwater Creek 

Shale (Dibblee, 1962, p. 8-11, pi. 1). It was named 

for Bitterwater Creek, 6 miles southwest of Maricopa, the type locality, where as much as 2,000 feet 

of this shale is exposed and is unconformably overlain by the Paso Robles Formation. This usage is 

adopted herein.

The Bitterwater Creek Shale was thought to be 

of Pliocene (?) age (Dibblee, 1962) because of its 

stratigraphic position as indicated; however, it contains foraminifers, fish scales, and diatoms diagnostic of the Mohnian Stage, late Miocene (R. L. Pierce, 

oral commun., 1967; Vedder, 1970). This age is the 

same as that of the Belridge Diatomite Member of 

the Monterey Shale, but the Bitterwater Creek Shale 

is stratigraphically higher (fig. 8).

The relationship of the Bitterwater Creek Shale 

to the unnamed Pliocene marine clastic sediments 

to the northwest, which were formerly included in 

the Bitterwater Creek Shale (Dibblee, 1962, pi. 1), 

is not clear because of insufficient exposures and 

structural complications. North of the Elkhorn Hills 

the Bitterwater Creek Shale intertongues northwestward into unfossiliferous sandstone with siliceous 

shale pebbles. This sandstone is similar to that of 

the unit mapped as unnamed marine sediment, of 

early Pliocene age. If the sandstones are the same, 

the Bitterwater Creek Shale is equivalent to at 

least the lower part of that unit. It is possible, however, that the Bitterwater Creek Shale and the unfossiliferous sandstone are overlapped by that unit 

and if so, are thus older. From the foregoing evidence the Bitterwater Creek Shale is considered to 

be late Miocene (Mohnian) and possibly early Pliocene in age.

REEF RIDGE SHALE

In the Reef Ridge and McLure Valley areas, 

about 500 feet of soft-weathering claystone is exposed that is transitional between the underlying 

Monterey Shale and overlying Etchegoin Formation. 

It was described and named the Reef Ridge Shale 

by Barbat and Johnson, 1933, p. 239; 1934, p. 1-17) 

and by Gester and Galloway (1933, p. 1174-1176). 

This usage was adopted by Woodring, Stewart, and 

Richards (1940, p. 119-122) and Stewart (1946, p. 

104, pi. 9) and is retained herein. This unit is arbitrarily placed at the top of the middle Tertiary 

sedimentary sequence. No type locality was designated, but Barbat and Johnson (1933, p. 4-5) stated 

that this shale unit is "typically exposed" from 

Little Tar Creek (9 miles south-southeast of Avenal) northwest for 22 miles to Jasper Creek (15 

miles west of Avenal). They assigned this shale 

unit to the uppermost Miocene. The type locality is 

herein designated as the exposure in Big Tar Creek 

(about 5 miles south-southwest of Avenal) in sees. 

7, 8, and 17, T. 23 S., R. 17 E., where the Reef Ridge 

Shale is about 550 feet thick.

According to Kleinpell (1938, p. 165), the Reef 

Ridge Shale contains foraminifers assigned to his 

Delmontian Stage, of latest Miocene age. His Delmontian Stage is, however, now considered to be 

part of, and inseparable from, his Mohnian Stage 

(R. L. Pierce, oral commun., 1970). Therefore, the 

Reef Ridge Shale of the type area is considered by 

Pierce to be of late Miocene age (Mohnian Stage). 

This age assignment, however, has not yet been 

doubtlessly ascertained, as it may range into early 

Pliocene.

Clay shale correlative with the Reef Ridge Shale 

does not crop out in the Temblor Range. Under the 

alluviated area to the east, however, wells penetrate 

between the Etchegoin Formation and Monterey 

Shale a shale unit from 150 to 900 feet thick that is 

referred to the Reef Ridge Shale by petroleum geologists. This shale unit was considered to be late Miocene and possibly early Pliocene in age and correlated with both the Reef Ridge Shale of Reef Ridge 

and the Belridge Diatomite Member of the Monterey 

Shale in the Temblor Range (Foss and Blaisdell, 

1960, p. 36). Correlation with the Reef Ridge Shale 

is probably valid because of its similar stratigraphic 

position and because in some wells, such as in the 

Elk Hills oil field, this unit is gray clay shale (J. C. 

Maher, oral commun., 1970) similar to the Reef 

Ridge Shale of Reef Ridge. Correlation with the 

Belridge Diatomite Member is considered not valid, 

as the Reef Ridge Shale is thought to be younger 

than that unit .because of reasons as indicated in 

the discussion of the Belridge Diatomite Member. 

Accordingly, then, the Reef Ridge Shale is probably 

correlative with the Bitterwater Creek Shale in the 

south end of the Temblor Range and is considered 

to be late Miocene and possibly early Pliocene in age.

UPPER TERTIARY SEDIMENTARY 

SEQUENCE

DEFINITION

In many places on both sides of the San Andreas 

fault, the middle Tertiary sedimentary sequence is
34 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

overain by shallow-water marine, brackish-water, 

and terrestrial sedimentary deposits mainly of Pliocene age. These deposits are informally designated 

herein as the upper Tertiary sedimentary sequence. 

The age of the sequence may range into early Pleistocene, depending upon the age interpretation of 

the fossils in the upper part.

This sequence underlies almost all the San Joaquin 

Valley east of the San Andreas fault. West of the 

fault it is restricted to Cuyama Valley, Carrizo 

Plain, and Salinas Valley and is exposed at only a 

few places along the margins of this alinement of 

valleys. The sequence must have accumulated in 

two northwest-trending basins separated by the 

Temblor Range, against which this sequence thins 

from both sides. In each of these basins the sequence 

is different in stratigraphy and thickness, as indicated subsequently.

DEPOSITS IN THE SAN JOAQUIN VALLEY AREA

The upper Tertiary sedimentary sequence of the 

part of the San Joaquin Valley region of figure 2 

accumulated in what developed (after middle Tertiary time) into a large marine embayment, in large 

part bounded on the southwest by uplifts that became the Temblor Range and the Diablo Range. 

Because this embayment covered the area that is 

now the San Joaquin Valley, it is commonly called 

the San Joaquin basin. The upper Tertiary sequence 

deposited in this basin is as thick as 7,000 feet and 

is composed mainly of fossiliferous interbedded 

sandstone, siltstone, and claystone of shallow marine origin with some brackish water and lacustrine 

beds at the top. The sequence crops out in the Reef 

Ridge and McLure Valley areas of the Diablo Range, 

and the upper part is exposed in the Kettleman 

Hills. In these areas it lies conformably on the Reef 

Ridge Shale and is overlain conformably by the 

Tulare Formation.

Southeast of McLure Valley and Kettleman Hills, 

this sedimentary sequence is concealed except for 

a few very small exposures in the foothills of the 

Temblor Range. Subsurface well data from east of 

the Temblor Range indicate that this sequence is 

about 7,000 feet thick, but it thins abruptly southwestward against previously deformed and eroded 

Monterey Shale of the Temblor Range.

TERMINOLOGY

The stratigraphic nomenclature applied to the 

upper Tertiary sedimentary sequence of the west 

side of San Joaquin Valley is much confused, as 

pointed out by Woodring, Stewart, and Richards 

(1940, p. 26-27). In the area north of Coalinga,

Anderson (1905, p. 178-181) originally named the 

entire exposed sequence "Etchegoin Beds," for exposures on "Etchegoin ranch, some twenty miles 

northeast of Coalinga" (this plots in the alluvium 

of San Joaquin Valley), but he called the lower 

two-thirds "Etchegoin Sands" and the upper third 

"San Joaquin Clays." Later, Arnold and Anderson 

(1910, p. 113-114) located this ranch in NW*4 sec. 

1, T. 19 S., R. 15 E., but designated the type section 

of the Etchegoin Formation on Anticline Ridge 

"9 miles north of Coalinga" and defined the formation as consisting of sand, gravel, and clay above 

"the Glycimerus zone."

On the east flank of the Diablo Range south of 

Coalinga and in the Kettleman Hills, Arnold and 

Anderson (1908, p. 46-55; 1910, p. 96-124) applied 

the term "Etchegoin Formation" to the upper twothirds of this sequence and named the lower third 

"Jacalitos Formation," which was inferred from 

the fossils to be of late Miocene age. This classification was adopted by Nomland (1916); however, a 

year later he (Nomland, 1917, p. 197) abandoned 

the name Jacalitos Formation because that unit is 

lithologically and paleontologically nearly similar to 

the Etchegoin, and he applied the term Etchegoin 

Formation or Group to both units and assigned both 

to the Pliocene.

In later years the San Joaquin Clay again became 

recognized as the upper third of the upper Tertiary 

sedimentary sequence in the west-side oil fields and 

the foothill areas (Reed, 1933, p. 236; Barbat and 

Galloway, 1934). In the Kettleman Hills this unit 

was formally defined and mapped as the San Joaquin 

Formation by Woodring, Stewart, and Richards 

(1940, p. 26-28) and adopted by Stewart (1946, 

p. 104-105, pi. 9). In both reports the name Jacalitos Formation was revived for the lower third, 

and Etchegoin Formation retained for the middle 

third of the upper Tertiary sedimentary sequence. 

They considered all three units to be of Pliocene age. 

Still later, Adegoke (1969, p. 28-34) recognized 

only a twofold division of this Pliocene sequence. 

He assigned the predominantly sandy lower twothirds to the Etchegoin Formation and the largely 

clayey upper one-third to the San Joaquin Formation, as shown in figure 13.

In the oil field subsurface areas east of the Temblor Range, Pack (1920, p. 44-47, pi. 1) and Woodring, Roundy, and Farnsworth (1932, p. 32-39) 

applied the term "Etchegoin Formation" to the 

entire Pliocene marine sedimentary sequence.

Although the lithology of the upper Tertiary sedimentary sequence is generally similar throughout, 

it is proposed to adopt the terminology proposed by
"d 

S

i

&

§ 

I

a

r

!

beds Etchegoin 

Clays Joaquin San Sands Etchegoin 

Formation Etchegoin Formation Jacalitos 

Group or Formation Etchegoin 

Group Etchegoin 

Formation Jacalitos 

Etchegoin Jacalitos

Sand Etchegoin 

Formation Etchegoin Formation Jacalitos 

Formation Etchegoin 

sandstone Blue 

\7 /\ \ 

\ / \ / \ 

\ \/ Formation Etchegoin 

V v 

Joaquin San 

Clay

Joaquin San 

Clay

Joaquin San 

Clay

Joaquin San 

Formation

Joaquin San 

Formation

Joaquin San 

Formation

Q. H- 

-i

(D VO O 

3

q > to 

go-o

E ~z 

Q. ? 0 

2 

O ^ 

53" !^I 

Q.

(D VO 

(D to 

Q. 00 

o

0 _ 

Q. 10 

-h

DO ^ 

0) O 

-i 0)_ ,_. 

^^

0) 

^ 3 

O (S ?0 ^ (? 1-1 

0- ? 0 P g ^ 

=!

^~

(D

-^

!^

o

(D

G

I

o

W

§

AnviNawiaas aoNanbas S8
36 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Adegoke (1969, p. 28-34) in dividing the sequence 

into the Etchegoin and San Joaquin Formations 

(fig. 13). The unit formerly called "Jacalitos Formation" is abandoned because it is neither lithologically nor paleontologically distinct from that 

called Etchegoin Formation. The lower two-thirds 

of this sequence is a series of alternating friable 

marine sandstones and siltstones and is designated 

as the Etchegoin Formation, whereas the upper onethird is mainly marine to brackish-water mudstone 

and is designated as the San Joaquin Formation, as 

shown in figure 14.

AGE

So, «/> c

'M <D

l»

? ? ?

? ?

0)

C 

0)

u

QL

FORMATION [SEQUE

' ^ «» - « *--%»OoOOO»»-_.._.

c.VJ'J r o" -~ Tulare Formation ~" ~ "" " ""

 0 0.-0000--.000 <...--.«>- --».-.--. .-

 ^, O OOOO O 0 OOOOOO------

.' :~ ~~- San Joaquin Formation - 

" BluejJ-^l' '^~rrr^fe ~ L .- - ' -; :

- -sandstone .^rr-^-,..,.. __. _..__.__....

----- -«- . . . _ _.. » . . _ ___ _ . . . . _ _ _ ... .

- - o -......__......._. _...... _... .......

- 0 <9 0 ---- ---_..

- - - . . .

- - o o » . . .

Miocene formations

NCE

(A >*i

0) (A

ra a.

> 9

0) 

0

> *

£ 3

ra CT

 r; 0)

t- w

<D ,. 

H £

»_ ra £ca»

D E

 o

(A

FIGURE 14. Valley deposits and upper Tertiary sedimentary 

sequence of the San Joaquin Valley area along east side 

of the southeastern part of the Diablo Range, Kettleman 

Hills, and the Temblor Range.

ETCHEGOIN FORMATION

The Etchegoin Formation, as redefined by Nomland (1917), Barbat and Galloway (1934), and 

Adegoke (1969, p. 26-28), is a series of semifriable 

sandstone and interbedded siltstone, claystone, and 

minor pebble conglomerate, all deposited under 

shallow-water marine conditions and presumably of 

Pliocene age. In a few places it contains thin strata 

of tuff. In the Reef Ridge it is about 5,200 feet 

thick, overlies the Reef Ridge Shale or the Monterey Shale, and is overlain by the San Joaquin 

Formation.

The type locality of the Etchegoin Formation has 

not been clearly designated. The formation was 

named by F. M. Anderson (1905) for "its characteristic development in the vicinity of Etchegoin

ranch" (in T. 19 S., R. 15 E.) north of Coalinga. 

He did not designate a type section, but Arnold and 

Anderson (1910, p. 113) stated: "The nearest locality to the Etchegoin ranch for which a description 

or section was given is 9 miles north of Coalinga, 

and this may therefore be taken as the type section." But on their map (Arnold and Anderson, 

1910, pi. 1) this "locality" plots several miles west 

of what they mapped as the Etchegoin Formation. 

From this confusion it may be said that the type 

section is within T. 19 S., R. 15 E., north of Coalinga, but its exact designation will not be made 

until that; area, which is far north of the area of 

figure 2, is more carefully mapped.

The most complete and best exposed section, which 

is herein designated as the reference section, is that 

north of Reef Ridge between Big Tar and Garza 

Creeks, Garza Peak quadrangle, or from 3 to 5 

miles southwest of Avenal (figs. 1, 2). The section 

there is about 5,200 feet thick and is conformable 

between the Reef Ridge Shale below and San Joaquin 

Formation above. In this section the Etchegoin Formation is composed of two parts, as recognized by 

Adegoke (1969, p. 28). The lower part (Basal 

Brown Sandstone Member of Adegoke, 1969, p. 28), 

about 3,500 feet thick, is mainly bedded commonly 

nodular brownish-gray sandstone and interbedded 

siltstone in about equal amounts and contains few 

fossils. This unit corresponds roughly to the unit 

formerly called Jacalitos Formation by earlier 

workers (fig. 13). The upper part (Upper Blue 

Sandstone Member of Adegoke, 1969, p. 28), about 

1,700 feet thick, is similar to the lower part; however, sandstones predominate and are somewhat 

coarser and commonly pebbly and (or) fossiliferous, 

and many of them are blue. This unit corresponds 

roughly to the formerly restricted Etchegoin Formation of Stewart (1946, p. 105, pi. 9). It is similar 

to and nearly equivalent to the "blue bed fades" 

mapped farther northwest by Rose and Colburn 

(1963, p. 33). Other places where this unit is exposed are in McLure Valley and Kettleman Hills.

On the geologic map (Dibblee, 1973b) only parts 

of the Upper Blue Sandstone Member of Adegoke 

(1969, p. 28) that are composed predominantly of 

blue sandstone are mapped separately from the rest 

of the Etchegoin Formation (fig. 14). In the Reef 

Ridge area there are several blue sandstone units, 

some as thick as 500 feet. Southeastward along 

strike all thin out or lose their distinctive blue 

color east of the Pyramid Hills. In McLure Valley 

the whole upper part of the Etchegoin Formation 

is composed of unfossiliferous massive blue sandstone, about 1,500 feet thick. In the Kettleman Hills
UPPER TERTIARY SEDIMENTARY SEQUENCE 37

(North and Middle Domes) several thin blue sandstone strata are present.

The blue sandstones are medium grained and 

commonly contain pebbles of black and variegated 

chert and andesite. The blue color of the sandstone 

is the effect of a thin blue coating on the grains.

The Etchegoin Formation of the Reef Ridge and 

Kettleman Hills areas contains abundant marine 

mollusks and echinoids of Pliocene age (Woodring 

and others, 1940, p. 102-103). In the Kettleman 

Hills (North Dome) and at a locality 10-12 miles 

north of Coalinga, a few mammalian remains from 

the upper part of the Etchegoin Formation are 

assigned to the late Hemphillian age, Pliocene (D. 

E. Savage, written commun. to C. A. Repenning, 

1968). In the Reef Ridge area, the few molluscan 

fossils from the lower part of the Etchegoin Formation are considered to be early Pliocene, and those 

from the upper part are considered to be late Pliocene (W. O. Addicott, oral commun., 1969).

SAN JOAQUIN FORMATION

In the Kettleman Hills the San Joaquin Formation, as mapped by Woodring, Stewart, and Richards 

(1940, p. 26-28, pi. 1), is from 1,200 to 1,800 feet 

thick and is mainly gray soft claystone, siltstone, 

and fine-grained sandstone. The base was taken as 

the base of a 50-foot-thick bed of gray to blue sandstone and pebble conglomerate (Cascajo Conglomerate Member of Woodring and others, 1940, p. 

49-53). The San Joaquin Formation overlies the 

Etchegoin Formation and grades upward into the 

Tulare Formation. The type locality of the San 

Joaquin Formation is on the northeast flank of Kettleman Hills, in sec. 23, T. 22 S., R. 18 E., 8 miles 

east of Avenal (fig. 1), as suggested by Barbat and 

Galloway (1934, p. 478-480); however, Woodring, 

Stewart, and Richards (1940, p. 27) suggested a 

better standard section 3 miles northwest in sec. 8, 

T. 22 S., R. 18 E.

In the foothills north of Reef Ridge, the San 

Joaquin Formation is about 2,000 feet thick and is 

similar to its exposure in Kettleman Hills. The base 

is taken as a thin pebble bed that overlies blue 

sandstone of the Etchegoin Formation. The San 

Joaquin Formation grades upward into the Tulare 

Formation through interbeds of conglomerate similar to that of the Tulare Formation. Southeastward 

along strike, the contact with the Tulare Formaion becomes difficult to map because the upper 1,200 

feet of the San Joaquin Formation contains increasing amounts of sandstone and many layers of shalepebble conglomerate, a composition like that of the 

Tulare Formation.

The San Joaquin Formation in the Kettleman 

Hills contains marine, brackish-water, and lacustrine fossils considered to be of late Pliocene age 

by Woodring, Stewart, and Richards (1940, p. 103). 

They reported (1940, p. 97-98) mammalian fossils 

from the "Pecten zone" about 600 feet below the 

top of this unit. These were considered by Durham, 

Jahns, and Savage (1954, p. 69) to be of Blancan 

age or late Pliocene and early Pleistocene age and 

by Hibbard, Ray, Savage, Taylor, and Guilday 

(1965, p. 512) to be early Blancan age or late 

Pliocene. Adegoke (1969, p. 51) suggested that part 

or all of the San Joaquin Formation may be of 

Pleistocene age. In the Reef Ridge foothills the San 

Joaquin Formation contains molluscan fossils that 

Addicott (oral commun., 1968) considered to be of 

late Pliocene age. The unit is tentatively assigned a 

late Pliocene age, but could range into the Pleistocene, depending on the interpretation of the Pliocene-Pleistocene boundary.

DEPOSITS IN THE SALINAS VALLEY 

CUYAMA VALLEY AREA

The upper Tertiary sedimentary sequence of the 

southeastern part of Salinas Valley, Carrizo Plain, 

Caliente Range, and Cuyama Valley is as thick as 

5,000 feet, but generally thinner. It accumulated in 

what developed after Miocene time into a large 

troughlike basin between the Temblor Range uplift 

on the northeast and an extensive uplift to the 

southwest that evolved into the Santa Lucia, La 

Panza and Sierra Madre Mountains (fig. 2). This 

trough apparently extended northwestward through 

Salinas Valley and may therefore be referred to as 

the Salinas basin. Most of the upper Tertiary sedimentary sequence lies southwest of the San Andreas 

fault; a small part is on the northeast side of the 

fault in a narrow strip between the fault and the 

Temblor Range uplift.

The upper Tertiary sedimentary sequence is terrestrial, except under Salinas Valley and in part of 

the strip on the northeast side of the San Andreas 

fault, where it is marine. In the central parts of the 

Salinas basin, this sequence conformably overlies 

the Santa Margarita or Caliente Formation, but 

along the flanks, especially the southwestern flank, 

it lies unconformably on all older formations, including the crystalline rocks. Where exposed, this sequence is unconformaibly overlain by the Paso Robles 

Formation.

UNNAMED MARINE SEDIMENTS

Several test holes drilled for petroleum in the 

Shandon area of the Salinas Valley southwest of 

the San Andreas fault passed through as much as
38 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

2,000 feet of marine sandstone and siltstone of 

probable Pliocene age below the Paso Robles Formation and above the Santa Margarita Formation. 

Because of its comparable age and stratigraphic 

position, this unit may be equivalent to the Pancho 

Rico Formation, as redefined by Durham and Addicott (1964, p. E4; 1965, p. A2-A5) in Salinas 

Valley northwest of figure 2.

In the narrow strip on the northeast side of 

the San Andreas fault east of Soda Lake is exposed 

about 2,000 feet of marine sandstone that overlies 

conglomerate of the Santa Margarita Formation 

and grades laterally northward and upward into the 

terrestrial Morales Formation. The relationship of 

this sandstone to the Bitterwater Creek Shale is 

discussed under that formation. This marine sandstone unit contains early Pliocene mollusks (Arnold 

and Johnson, 1910, p. 89; W. 0. Addicott, oral 

commun., 1967). It may be correlative with the 

marine unit in the Shandon area described previously and also with part of the lithologically similar Etchegoin Formation of San Joaquin Valley and 

the Diablo Range.

QUATAL FORMATION

In the eastern Caliente Range, red beds of the 

Caliente Formation are overlain conformably by as 

much as 700 feet of lacustrine gray claystone. This 

claystone is believed to correlate, on the basis of 

similar lithology and stratigraphic position, with 

the Quatal Formation named by Hill, Carlson, and 

Dibblee (1958, p. 2996-2997) for Quatal Canyon 

near the type locality, in the Cuyama badlands southeast of the Caliente Range and beyond the southeast 

border of figure 2. This name is herein adopted for 

this claystone in both exposures.

The Quatal Formation, which conformably underlies the terrestrial Morales Formation, is exposed at 

only a few places other than in the Caliente Range. 

In the Cuyama badlands it is composed of about 400 

feet of reddish-brown claystone and gypsum that 

overlies the Caliente Formation. South of Cuyama 

Valley it is composed of 200-400 feet of white sandstone and red clay that disconformably overlies the 

Santa Margarita Formation and Branch Canyon 

Sandstone. In San Juan Creek, northwest of Carrizo 

Plain, about 200 feet of gray clay assigned to the 

Quatal Formation disconformably overlies the Santa 

Margarita Formation.

The Quatal Formation was presumed by Hill, Carlson, and Dibblee (1958, p. 2996) to be of late Miocene age because of its stratigraphic position. In the 

Caliente Range the uppermost beds of the Caliente 

Formation that underlie the Quatal contain mammalian remains diagnostic of Hemphillian age, Pliocene (Savage, 1957, p. 1845), and beds about 1,600 

feet above the base of the overlying Morales Formation contain a few mammalian remains of Blancan 

age (James, 1963, p. 11; Repenning and Vedder, 

1961). The relationship of the Quatal Formation to 

the Pliocene (?) marine sediments of the Shandon 

area to the northwest is concealed, but the Quatal is 

presumably younger. Because of its stratigraphic 

position, the Quatal Formation is herein inferred to 

be of Hemphillian age and is assigned to the Pliocene.

MORALES FORMATION

In the Cuyama Valley, Caliente Range, and in the 

area northwest of Carrizo Plain is exposed a deformed valley deposit, as much as 5,000 feet thick, 

of light-gray gravel, sand, and silt that conformably 

overlies the Quatal Formation and unconformably 

laps onto the middle Tertiary sedimentary sequence. 

This valley deposit was named the Morales Member 

of the Santa Margarita Formation by English (1916, 

p. 203, pi. XIX) for Morales Canyon (10 miles northwest of New Cuyama), the type locality. This deposit 

was redefined as a formation by Hill, Carlson, and 

Dibblee (1958, p. 2990, 2996-2998) because it differs 

lithologically from the Santa Margarita Formation 

and in the type locality in unconformably overlies 

the Santa Margarita Formation with angular discordance. The usage of Morales Formation of Hill, 

Carlson, and Dibblee (1958) and Vedder (1970) is 

retained herein.

The Morales Formation was inferred to be of Pliocene age by Hill, Carlson, and Dibblee (1958, p. 

2996-2998) on the basis of its stratigraphic position 

above the Quatal Formation and Miocene strata and 

because of its unconformable relationship below 

equivalents of the Paso Robles Formation in western 

Cuyama Valley and eastern Caliente Range and at 

San Juan Creek northwest of Carrizo Plain.

A tooth of Equus (Pleisohippus) sp. (large 

horse), considered diagnostic of Blancan age (Pliocene or Pleistocene) of the vertebrate chronology, 

was found near the middle of the 5,000-foot-thick 

Morales Formation in the eastern Caliente Range 

(Vedder and Repenning, 1965; Vedder, 1970). The 

profound deformation of this formation, however, 

as compared to the much less deformed unconformably overlying Paso Robles Formation indicates 

that the Morales Formation probably is late Pliocene in age, to which it was assigned by Vedder 

(1970).

In the Panorama Hills and southwestern foothills 

of the Temblor Range just northeast of the San 

Andreas fault, as much as 2,500 feet of terrestrial
VALLEY DEPOSITS 39

gravel named Panorama Hills Formation by Dibblee 

(1962, p. 8, pi. 1) gradationally overlies sandstone 

of the unnamed marine sediments and is unconformably overlain by the Paso Robles Formation. 

The name Panorama Hills Formation is herein 

abandoned, and this unit is assigned to the Morales 

Formation because it is of similar lithology and is 

probably in large part correlative. Presumably this 

valley deposit accumulated in the same basin as 

the Morales Formation now exposed in the Caliente 

Range and Cuyama Valley.

VALLEY DEPOSITS

DEFINITION

Alluvial deposits of Pleistocene and possibly late 

Pliocene age form the uppermost and youngest 

thick sedimentary unit of the map area. These are 

informally designated herein as valley deposits. 

They accumulated in the San Joaquin and Salinas 

basins after the sea completely withdrew from this 

region near or at the end of Pliocene time. These 

basins thereby became valleys, separated by the 

Temblor-Diablo Range uplift, which was rising on 

the northeast side of the San Andreas fault. The 

valley deposits southwest of this uplift are commonly called the Paso Robles Formation; these 

accumulated in a long valley that extended from 

what is now the Salinas Valley southeastward 

through Carrizo Plain into Cuyama Valley. The 

valley deposits northeast of the Temblor-Diablo 

Range uplift are commonly called the Tulare Formation, and they accumulated in the San Joaquin Valley.

PASO ROBLES FORMATION

Dissected locally deformed valley deposits in upper Salinas Valley were named the Paso Robles Formation by Fairbanks (1898, p. 565-566) for exposures near Paso Robles (fig. 1). This name has since 

been applied to these deposits beyond the Paso 

Robles area by Fairbanks (1904), Arnold and Johnson (1910, pi. 1), Bramlette and Daviess (1944), 

Dibblee (1962, p. 6-10, pi. 1), and Durham (1963, 

1964, 1966) and is used herein.

In the Salinas Valley lowland area north of the 

La Panza Range, the Paso Robles Formation is as 

much as 1,500 feet in exposed thickness; it attains 

a total maximum thickness of more than 4,000 feet 

in the subsurface west of Shandon as indicated 

from well logs. In this lowland area this valley 

deposit is composed of pebble gravel, sand, and 

clay, derived from the La Panza Range and from 

mountains west of Salinas Valley. In the subsurface 

near Shandon it conformably (?) overlies the unnamed Pliocene marine sediments (Pancho Rico(?) 

Formation) as indicated by well logs. In the La 

Panza Range and Red Hills, this valley deposit thins 

and unconformably laps over the previously deformed middle Tertiary sedimentary sequence onto 

the crystalline basement complex.

Under the Carrizo Pain, the Paso Robles Formation is as thick as 2,000 feet near the San Andreas 

fault as indicated from well logs, and is composed 

largely of shale-pebble gravel, sand, and clay, derived mainly from the Temblor Range. Southwestward this valley deposit thins and buttresses out 

against previously deformed Morales and Quatal 

Formations and the middle Tertiary sedimentary 

sequence of the Caliente Range.

At and near the southeast end of the Caliente 

Range and southwest of the San Andreas fault, the 

Paso Robles Formation ("deformed fanglomerate 

from eastern sources" of Vedder and Repenning, 

1965, and "deformed alluvial deposits" of Vedder, 

1970) is as thick as 1,000 feet and is unconformable 

on previously deformed lower, middle, and upper 

Tertiary sequences, including the Morales Formation. The Paso Robles Formation is there composed 

of gravel and some landslide debris of rocks exposed 

in the San Emigdio Mountains across the fault, but 

now is some 20 miles southeast of this area, owing 

to that much strike-slip on the fault since deposition of this detritus.

Northeast of the San Andreas fault, the Paso 

Robles Formation is as thick as 2,000 feet and 

more adjacent to the fault, but thins out rapidly 

northeastward against the Temblor Range. It unconformably overlies rocks of the Temblor Range, 

including the Morales Formation, and was derived 

entirely from the Temblor Range.

In Cuyama Valley, equivalents of the Paso Robles 

Formation are thought to be the old dissected 

locally deformed alluvial fan deposits, such as several on the southwest side of the Caliente Range and 

one southwest of New Cuyama. These deposits are 

as thick as 600 feet and are composed of coarse 

locally derived detritus.

The top of the Paso Robles Formation, where 

preserved from erosion, is a surface of deposition, 

or an old valley surface that was never buried. 

Carrizo Plain, where it is preserved under a thin 

cover of alluvium, is a remnant of this former very 

extensive valley surface of deposition. To the northwest and west this old valley surface becomes increasingly dissected and largely destroyed by downcutting stream channels of the present Salinas River 

drainage system. Along its margins this old valley
40 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

surface of deposition blends into the old erosion 

surface of the La Panza, Caliente, and Temblor 

Ranges as the Paso Robles Formation thins out 

against those previously elevated areas.

The age of the Paso Robles Formation can only 

be inferred from its stratigraphic position and 

from geomorphic relations because, except in one 

place, no diagnostic fossils have been found. This 

formation has been variously inferred to be Pliocene, Pleistocene, or Pliocene and Pleistocene in age. 

Durham (1966, p. B22) and Galehouse (1967, p. 

955-956) considered it to be Pliocene and possibly 

Pleistocene in age because of the apparent intertonguing relationship with the underlying marine 

Pancho Rico Formation (lower Pliocene) east and 

southeast of King City. In that part of Salinas Valley (northwest of fig. 2), however, the Paso Robles 

Formation is thin, and some of the lower beds into 

which marine beds intertongue may be equivalent 

to the Morales or Quatal Formations farther southeast.

The Paso Robles Formation must be at least in 

part of Pleistocene age because its top surface of 

deposition, which blends into the Pleistocene erosion 

surface of the adjacent mountains where this surface is cut on units as young as the Morales Formation, is in large part preserved, whereas no surface 

of deposition of any Tertiary formation remains 

unburied and uneroded. The angular unconformable 

relationship of the Paso Robles Formation to all 

older units, including the Morales Formation of late 

Pliocene age, suggests that all the Paso Robles Formation in areas in which this relationship exists is 

of Pleistocene age.

The single locality in which fossils were found 

in the Paso Robles Formation is 2 miles east of 

Atascadero in a roadcut about 300 feet west of 

middle of west line of sec. 7, T, 28 S., R. 13 E. At 

that place, brackish-marine mollusks were found 

(by J. S. Galehouse) in shale-pebble gravel about 

20 feet above the base of the Paso Robles Formation. W. O. Addicott (written commun., 1971) considered them probably Pliocene, possibly middle 

Pliocene. Also found at this locality, and in basal 

cobble gravel of this formation within 3 miles southeast of Santa Margarita, are cobbles with molluskbored holes.

Although the Paso Robles Formation is generally 

regarded as Pliocene and Pleistocene (?) in age, the 

formation within the area of figure 2 is considered 

by the writer to be of Pleistocene age and in places 

partly of probable late Pliocene age because of the 

stratigraphic relations and fossil data as indicated.

TULARE FORMATION

Locally deformed dissected valley deposits composed of gravel, sand, and silt in the hills on the 

southwest side of the San Joaquin Valley near 

Coalinga were named Tulare Formation by Anderson (1905, p. 181) for nearby Tulare Lake. No type 

locality was then designated, but Woodring, Stewart, 

and Richards (1940, p. 13) suggested the exposures 

on the northeast flank of the northern part of Kettleman Hills North Dome as the type section. The 

name Paso Robles Formation was also applied to 

these valley deposits by Anderson and Pack (1915, 

pi. 1) and to those in the Temblor Range by Pack 

(1920, pi. II, p. 47-52). These deposits in the Temblor Range, however, were included earlier by 

Arnold and Johnson (1910, pi. 1) in a unit they 

named McKittrick Formation. These valley sediments were redesignated the Tulare Formation by 

Woodring, Roundy, and Farnsworth (1932, p. 16- 

30), Dibblee (1962, p. 8-10, pi. 1), and Foss and 

Blaisdell (1968 p. 35) because, even though they 

are lithologically similar to and occupy the same 

stratigraphic position as does the Paso Robles Formation, they were deposited in a different basin or 

valley. This usage is retained herein.

In the foothills of the Diablo Range and in the 

Kettleman Hills, the Tulare Formation is about 

2,700 feet thick and grades downward into the San 

Joaquin Formation. Well data in the subsurface of 

the Elk Hills, Buena Vista Hills, and east of the 

Temblor Range indicate that it is similar. In the 

foothills of the Temblor Range it thins out westward against the unconformably underlying Etchegoin Formation and Monterey Shale. The top of 

the Tulare Formation is a valley surface of deposition that forms the present undissected surface of 

San Joaquin Valley under a thin mantle of alluvium 

but is severely dissected, though partly preserved, 

where it is elevated by deformation in the Elk Hills, 

Buena Vista Hills (east of Taft), and foothills of 

the Temblor Range.

The age of the Tulare Formation is inferred to 

be late Pliocene and Pleistocene (Arnold and Anderson, 1910, p. 140, 154; Pack, 1920, pi. II; Woodring 

and others, 1932, p. 27, and 1940, p. 104; Stewart, 

1946, p. 105; Wahrhaftig and Birman, 1965, p. 314r316) or Pleistocene (Goudkoff, 1943, p. 248-249; 

McMasters, 1947, fig. 34; Foss and Blaisdell, 1968, 

p. 35). A few mammalian fossils found in the San 

Joaquin Formation just below the base of the Tulare Formation in the Kettleman Hills and near 

McKittrick are diagnostic of the Blancair age, late 

Pliocene or Pleistocene (C. A. Repenning, oral
SURFICIAL DEPOSITS 41

commun., 1968). On 

the Tulare Formation 

cene and Pleistocene 

commun., 1968).

The Tulare Formation 

is probably correlative 

Paso Robles Formation 

lithology, stratigraph 

relations and is likewise 

Pliocene (?) and Pleistocene

the basis of diatom studies, 

is considered to be of Plioage (K. E. Lohman, written

within the area of figure 2 

with most of if not all the 

on the basis of its similar 

ic position, and geomorphic 

tentatively assigned a late 

age.

SURFICIAL DEPOSITS

Surficial deposits consist of older alluvium, alluvium, and landslides. These deposits are generally 

undeformed, except along or near the San Andreas 

fault. They are generally unconformable on older 

formations, except in much of the San Joaquin 

Valley and Carrizo Plain, where they may be conformable on the Tulare and Paso Robles Formations where these formations are undeformed.

The older alluvium, which is as thick as 400 feet 

and includes terrace deposits, is dissected where 

elevated. At the tar seeps a mile south of McKittrick, terrace sands yielded a large mammalian 

fauna (Schultz, 1938) of Rancholabrean age late 

Pleistocene (C. A. Repenning, oral commun., 1969).

The alluvium forms a thin cover, generally less 

than 100 feet thick, on the valleys and flood plains 

of canyons. The alluvium and landslides are mainly 

of Holocene age, but may be in part latest Pleistocene, depending upon the interpretation of when 

the Holocene started.

RELATIONSHIP OF SEDIMENTARY

SEQUENCES TO THE SAN

ANDREAS FAULT

It may be noted throughout this report that the 

successively older sedimentary sequences are increasingly different on opposite sides of the San 

Andreas fault and that the basement complex upon 

which they rest is totally different. This condition 

appears to be the result of cumulative right-lateral 

displacement on this fault since Cretaceous (or 

Jurassic) time, along which areas of dissimilar 

older sequences and rocks have been juxtaposed, 

almost exactly as inferred by Hill and Dibblee 

(1953).

In the environs of the Carrizo Plain, it was found 

that the Paso Robles Formation on the northeast 

side of the San Andreas fault and also just southwest of it is composed of detritus derived from the 

mountains on the northeast side and that these 

detrital sediments on the southwest side have been 

shifted some 10-15 miles northwest from their

sources on the northeast side (Hill and Dibblee, 

1953, p. 446; Dibblee, 1973t>).

The Pliocene marine sediments (Pancho Rico(?) 

Formation and its equivalent) on the northeast side 

of the fault extend some 50-60 miles farther southeast than they do on the southwest side, suggesting 

a right-lateral shift of that amount since they were 

deposited.

The spectacular difference in stratigraphy of the 

middle Tertiary sedimentary sequence on opposite 

sides of the fault, with sudden changes of fades at 

the fault as shown in figure 12, is almost certainly 

due to lateral juxtaposition of once distant areas. 

The juxtaposition of the all-marine (in part 

bathyal) fades of the northeast block against coarse 

terrestrial facies, which in large part grades laterally westward into shallow marine facies on the 

southwest block, is difficult to account for otherwise.

A right-lateral offset of about 65 miles on the 

fault since late Miocene time was estimated by Hill 

and Dibblee (1953, p. 446-448) from the offset on 

the fault of the transition facies zone where the 

terrestrial sediments grade laterally westward into 

marine sediments. On the northeast block this zone 

is in the San Emigdio Mountains (southeast of 

Maricopa, fig. 1); on the southwest block, it is 

some 100 miles farther northwest, just northwest 

of Cholame, suggesting a right-lateral displacement 

of that amount. Further evidence suggesting that 

much displacement is the occurrence, in the upper 

Miocene Santa Margarita Formation of the Temblor 

Range northeast of the fault, of landslide (?) masses 

and coarse detritus of crystalline basement rocks 

presumably derived from those rocks in the Gabilan 

Range (north of King City, fig. 1) southwest of the 

fault but now more than 80 miles to the northwest 

(Dibblee, 1962, p. 8). This post-Miocene rightlateral displacement may be as much as 150 miles, 

as inferred by Huffman (1970, p. 105-106) from 

matching the coarse conglomerate and breccia of 

this formation in the Temblor Range with their 

probable bedrock source in the Gabilan Range west 

of the San Andreas fault.

Right-lateral offset of some 175 miles since early 

Miocene time was suggested by Hill and Dibblee 

(1953, p. 448-449) on the basis of a similar assemblage of volcanic rocks and terrestrial and marine 

sedimentary rocks of early Miocene age in the 

northern Gabilan Range on the southwest side of 

the fault and in the San Emigdio Mountains on the 

northeast side. Radiometric age dates of 21.5 million 

years obtained from the volcanic rocks in both areas 

by D. L. Turner (1970, p. 101; oral commun., 

1970) reaffirm this inferred offset.
42 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

The lower Tertiary and Cretaceous sedimentary 

sequences, although composed almost entirely of 

marine clastic rocks, are very unlike in stratigraphy, 

thickness, and age range on opposite sides of the 

fault within the region of figure 2. This condition 

must also be the result of juxtaposition along the 

fault of areas once far distant. To ascertain Hill 

and Difoblee's (1953, p. 448-449) estimated rightlateral offset on the fault of possibly 225 miles since 

Eocene time, 320 miles since Cretaceous time, and 

350 miles since Jurassic time, it is necessary to go 

far beyond the borders of figure 2, which is also 

beyond the scope of this report.

It may be concluded that the stratigraphy of the 

region within figure 2 is closely related and greatly 

affected by movements on and near the San Andreas 

fault and that the available evidence suggests that 

this fault was active, either recurrently or continuously, since Jurassic or Cretaceous time.

In summary, it may be said that the northeast 

block is one of oceanic basement of eugeosynclinal 

sedimentary and mafic igneous rocks overlain by 

four sequences of bathyal to shallow-water marine 

sedimentary rocks, whereas the southwest block is 

one of continental basement of granitic and metasedimentary rocks overlain unconformably by three 

sequences of shallow-water marine and terrestrial 

sedimentary and minor volcanic rocks. It seems evident that the southwest block was shifted northwestward relative to and along the northeast block 

by many tens of miles of cumulative right-slip on 

the San Andreas fault during the Cenozoic Era.

REFERENCES CITED

Adegoke, O. S., 1969, Stratigraphy and paleontology of the 

marine Neogene formations of the Coalinga region, California: California Univ. Pubs. Geol. Sci., v. 80, 241 p., 

13 pis., figs., maps.

Anderson, F. M., 1905, A stratigraphic study in the Mount 

Diablo Range of California: California Acad. Sci. Proc., 

3d ser., Geology, v. 2, p. 155-248.

 1908, A further stratigraphic study in the Mount 

Diablo Range of California: California Acad. Sci. Proc., 

4th ser., v. 3, p. 1-40.

Anderson, F. M., and Martin, Bruce, 1914, Neocene record in 

the Temblor Basin, California, and Neocene deposits of 

the San Juan district, San Luis Obispo County: Calif. 

Acad. Sci. Proc., 4th ser., v. 4, p. 15-112.

Anderson, Robert, and Pack, R. W., 1915, Geology and oil 

resources of the west border of the San Joaquin Valley 

north of Coalinga, California: U.S. Geol. Survey Bull. 

603, 220 p.

Arnold, Ralph, and Anderson, Robert, 1908, Preliminary report on the Coalinga oil district, Fresno and Kings 

Counties, California: U.S. Geol. Survey Bull. 357, 142 p.

 1910, Geology and oil resources of the Coalinga district, California: U.S. Geol. Survey Bull. 398, 354 p., 52 

pis.

Arnold, Ralph, and Johnson, H. R., 1910, Preliminary report 

on the McKittrick-Sunset oil region, Kern and San Luis 

Obispo Counties, California: U.S. Geol. Survey Bull. 

406, 225 p.

Atwill, E. R., 1935, Oligocene Tumey formation of California: 

Am. Assoc. Petroleum Geologists Bull., v. 19, no. 8, p. 

1192-1204.

Bailey, E. H., Irwin, W. P., and Jones, D. L., 1964, Franciscan and related rocks, and their significance in the 

geology of western California: California Div. Mines 

and Geology, Bull. 183, p. 1-177.

Bailey, W. C., 1939, Wasco oil field [California] California 

Oil Fields Summ. Operations, v. 24, no. 3, p. 66-71 

[1941].

Bandy, O. L., and Arnal, R. E., 1969, Middle Tertiary basin 

development, San Joaquin Valley, California: Geol. Soc. 

America Bull., v. 80, p. 783-819.

Barbat, W. F., and Galloway, John, 1934, San Joaquin clay, 

California: Am. Assoc. Petroleum Geologists Bull., v. 

18, no. 4, p. 476-499.

Barbat, W. F., and Johnson, F. L., 1933, Stratigraphy and 

foraminifera of the Reef Ridge shale, upper Miocene, 

California [abs.]: Pan-Am. Geologist, v. 59, no. 3, p. 

239; also, 1934, Jour. Paleontology, v. 8, no. 1, p. 1-17.

Blake, W. P., 1855, Notice of remarkable strata containing 

the remains of Infusoria and Polythalmia in the Tertiary formation of Monterey, California: Acad. Nat. 

Sci. Philadelphia Proc., v. 7, p. 328-331.

Bramlette, N. M., and Daviess, S. N., 1944, Geology and oil 

possibilities of the Salinas Valley, California: U.S. Geol. 

Survey Oil and Gas Inv. Prelim. Map 24.

Chipping, D. H., 1972, Early Tertiary paleogeography of 

central California: Am. Assoc. Petroleum Geologists 

Bull., v. 56, no. 3, p. 480-493.

Church, C. C., 1968, Lower Cretaceous Foraminifera of the 

Orchard Peak-Devils Den area, California: California 

Acad. Sci., Proc., 4th ser., v. 32, no. 18, p. 523-580, 8 pis.

Clark, B. L., 1929, Tectonics of the Valle Grande of California: Am. Assoc. Petroleum Geologists Bull., v. 13, 

no. 3, p. 199-238.

Clark, B. L., and Vokes, H. E., 1936, Summary of marine 

Eocene sequence of western North America: Geol. Soc. 

America Bull., v. 47, no. 6, p. 851-878.

Clark, L. M., and Cl-ark, Alexander, 1935, The Vaqueros 

in the Temblor Range [abs.]: Am. Assoc. Petroleum 

Geologists Bull., v. 19, no. 1, p. 137.

Clements, T. D., 1950, Geology of Cuyama Gorge, California 

[abs.]: Read before Am. Assoc. Petroleum Geologists, 

Los Angeles, Calif., October 20, 1950.

Corey, W. H., 1954, Tertiary basins of southern California, 

pt. 8 in chap. 3 of Jahns, R. H., ed. Geology of southern 

California: California Div. Mines Bull. 170, p. 73-83.

Cross, R. K., 1962, Geology of the Carrizo-Cuyama Basin, 

in Guidebook to the geology of Carrizo Plain and San 

Andreas Fault, San Joaquin Geol. Soc. and Pacific Sees. 

Am. Assoc. Petroleum Geologists and Soc. Econ. Paleontologists and Mineralogists: p. 27-35.

Cunningham, G. M., and Barbat, W. F., 1932, Age of producing horizons at Kettleman Hills, California: Am. Assoc. 

Petroleum Geologists Bull., v. 16, no. 4, p. 417-421.

Curran, J. F., 1943, Eocene stratigraphy of the Chico Martinez Creek area, Kern County, California: Am. Assoc. 

Petroleum Geologists Bull., v. 27, no. 10, p. 1361-1386.
REFERENCES CITED 43

Curtis, G. H., Evernden, J. F., and Lipson, J. I., 1958, Age 

determination of some granitic rocks in California by 

the potassium-argon method: California Div. Mines Spec. 

Kept. 54, 16 p.

Cushman, J. A., and Goudkoff, P. P., 1938, New species of 

Pulvinulinella from the California Miocene: Cushman 

Lab. Foram. Research, Contr. v. 14, pt. 1, pi. 1.

Cushman, J. A., and Siegfus, S. S., 1942, Foraminifera from 

the Kreyenhagen Shale of California: San Diego Soc. 

Nat. History Trans., v. 9, no. 34, p. 385-426, pis. 14-19.

Dibblee, T. W., Jr., 1962, Displacements on the San Andreas 

rift zone and related structures in Carrizo Plain and 

vicinity, in Guidebook to the geology of Carrizo Plain 

and San Andreas fault, San Joaquin Geol. Soc. and 

Pacific Sees. Am. Assoc. Petroleum Geologists and Soc. 

Econ. Paleontologists and Mineralogists: p. 5-12, pi. 1.

 1968, Geologic map of Temblor Range, San Luis 

Obispo and Kern Counties, California, in Guidebook to 

geology and oil fields of west side southern San Joaquin 

Valley, Am. Assoc. Petroleum Geologists and Soc. Econ. 

Paleontologists and Mineralogists, Pacific Sees., Ann. 

Field Trip, 1968: In pocket.

 1973a, Geologic map of the Shandon and Orchard 

Peak quadrangles, California, showing Mesozoic and 

Cenozoic rock units juxtaposed along the San Andreas 

fault: U.S. Geol. Survey Misc. Geol. Inv. Map 1-788 

[in press],

1973b, Regional geologic map of San Andreas and

related faults in Carrizo Plain, Temblor, Caliente, and 

La Panza Ranges and vicinity, California: U.S. Geol. 

Survey Misc. Geol. Inv. Map 1-757 [in press].

Dickinson, W. R., 1963, Tertiary stratigraphic sequence of 

the Hancock Ranch area, Monterey and Kings Counties, 

California, in Guidebook to the geology of Salinas Valley and the San Andreas fault, Am. Assoc. Petroleum 

Geologists and Soc. Econ. Paleontologists and Mineralogists, Pacific Sees., Ann. Field Trip, 1963: p. 47-53.

 1966a, Structural relationships of San Andreas fault 

system, Cholame Valley and Castle Mountain Range, 

California: Geol. Soc. America Bull., v. 77, no. 7, p. 

707-726.

1966b, Table Mountain serpentine extrusion in California Coast Ranges: Geol. Soc. America Bull., v. 77, 

no. 5, p. 451-472.

Diller, J. S., and Stanton, T. W., 1894, The Shasta-Chico 

series: Geol. Soc. America Bull., v. 5, p. 435-464.

Durham, D. L., 1963, Geology of the Reliz Canyon, Thompson Canyon, and San Lucas quadrangles, Monterey 

County, California: U.S. Geol. Survey Bull. 1141-Q, p. 

Q1-Q41.

 1964, Geology of the Cosio Knob and Espinosa Canyon 

quadrangles, Monterey County, California: U.S. Geol. 

Survey Bull. 1161-H, p. H1-H29.

1966, Geology of the Hames Valley, Wunpost and

Valleton quadrangles, Monterey County, California: 

U.S. Geol. Survey Bull. 1221-B, p. B1-B53.

Durham, D. L., and Addicott, W. O., 1964, Upper Miocene 

and Pliocene marine stratigraphy in southern Salinas 

Valley, California: U.S. Geol. Survey Bull. 1194-E, p. 

E1-E7 [1965].

 1965, Pancho Rico Formation, Salinas Valley, California: U.S. Geol. Survey Prof. Paper 524-A, p. AlA22.

Durham, J. W., 1942, Reef corals from the California middle 

Eocene: California Acad. Sci. Proc., 4th ser., v. 23, no. 

34, p. 503-510.

 1954, The marine Cenozoic of southern California, pt. 

4, in chap. 3 of Jahns, R. H., ed., Geology of southern 

California: California Div. Mines Bull. 170, p. 23-32.

Durham, J. W., Jahns, R. H., and Savage, D. E., 1954, 

Marine-nonmarine relationships in the Cenozoic section 

of California, pt. 7, in chap. 3 of Jahns, R. H., ed., 

Geology of southern California: California Div. Mines 

Bull. 170, p. 59-71.

Eaton, J. E., 1939, Geology and oil possibilities of Caliente 

Range, Cuyama Valley and Carrizo Plain, California: 

California Jour. Mines and Geol., v. 35, no. 3, p. 255- 

274.

Eaton, J. E., Grant, U. S., and Alien, H. B., 1941, Miocene of 

Caliente Range and environs, California: Am. Assoc. 

Petroleum Geologists Bull., v. 25, no. 2, p. 193-262.

Elliot, W. J., Tripp, Eugene, and Karp, S. E., 1968, Road 

guides, in Guidebook to geology and oil fields of west 

side southern San Joaquin Valley, Am. Assoc. Petroleum 

Geologists, Soc. Econ. Geophysicists, and Soc. Econ. 

Paleontologists and Mineralogists, Pacific Sees., Ann. 

Field Trip, 1968: p. 102-142.

English, W. A., 1916, Geology and oil prospects of Cuyama 

Valley, California: U.S. Geol. Survey Bull. 621-M, p. 

191-214.

 1918, Geology and oil prospects of the Salinas Valley-Parkfield area, California: U.S. Geol. Survey Bull. 

691-H, p. 219-250.

1921, Geology and petroleum resources of northwestern Kern County, California: U.S. Geol. Survey 

Bull. 721, 48 p.

Evernden, J. F., Savage, D. E., Curtis, G. H., and James, G. 

T., 1964, Potassium-argon dates and Cenozoic mammalian chronology of North America: Am. Jour. Sci., v. 

262, no. 2, p. 145-198.

Fairbanks, H. W., 1898, Geology of a portion of the southern Coast Ranges: Jour. Geology, v. 6, no. 6, p. 551-576.

 1904, Description of the San Luis quadrangle [California] : U.S. Geol. Survey Geol. Atlas, Folio 101, 14 p.

Fletcher, G. L., 1962, The Recruit Pass area of the Temblor 

Range, San Luis Obispo and Kern Counties, California, 

in Guidebook to the geology of Carrizo Plain and San 

Andreas fault, San Joaquin Geol. Soc. and Pacific Sees. 

Am. Assoc. Petroleum Geologists and Soc. Econ. Paleontologists and Mineralogists: p. 16-20.

Foss, C. D., and Blaisdell, Robert, 1968, Stratigraphy of the 

west side of southern San Joaquin Valley, in Guidebook 

to geology and oil fields of west side southern San 

Joaquin Valley, Am. Assoc. Petroleum Geologists, Soc. 

Econ. Geophysicists, and Soc. Econ. Paleontologists and 

Mineralogists, Pacific Sees., Ann. Field Trip, 1968: p. 

33-43.

Gabb, W. M., 1869, Cretaceous and Tertiary fossils: California Geol. Survey, Paleontology, v. 2, 299 p. 36 pis.

Galehouse, J. S., 1967, Provenance and paleocurrents of the 

Paso Robles Formation, California: Geol. Soc. America 

Bull., v. 78, no. 8, p. 951-978.

Gester, C. G., and Galloway, John, 1933, Geology of Kettleman Hills oil field, California: Am. Assoc. Petroleum 

Geologists Bull., v. 17, no. 10, p. 1161-1193.
44 STRATIGRAPHY, SOUTHERN COAST RANGES NEAR SAN ANDREAS FAULT, CALIFORNIA

Goudkoff, P. P., 1934, Subsurface stratigraphy of Kettleman Hills oil fields: Am. Assoc. Petroleum Geologists 

Bull., v. 18, no. 4, p. 435-475.

 1943, Correlation of oil field formations on the west 

side of San Joaquin Valley [California]: California Div. 

Mines Bull. 118, p. 247-252.

1945, Stratigraphic relations of upper Cretaceous in

Great Valley, California: Am. Assoc. Petroleum Geologists Bull., v. 29, no. 7, p. 956-1007.

Hamlin, Homer, 1904, Water resources of the Salinas Valley, California: U.S. Geol. Survey Water-Supply and 

Irrigation Paper 89, 91 p.

Hay, E. A., 1963, Age and relationships of the Gold Hill 

pluton, Cholame Valley, California, in Guidebook to the 

geology of Salinas Valley and San Andreas fault, Am. 

Assoc. Petroleum Geologists and Soc. Econ. Paleontologists, Pacific Sees., Ann. Field Trip, 1963: p. 113-115.

Heikkila, H. H., and MacLeod, G. M., 1951, Geology of Bitterwater Creek area, Kern County, California: California 

Div. Mines Spec. Rept. 6, 21 p.

Henny, Gerard, 1930, McLure shale of the Coalinga region, 

Fresno and Kings Counties, California: Am. Assoc. 

Petroleum Geologists Bull., v. 14, no. 4, p. 403-410.

Hibbard, C. W., Ray, C. E., Savage, D. E., Tayk>r, D. W., 

and Guilday, J. E., 1965, Quaternary mammals of North 

America, in The Quaternary of the United States: 

Princeton, N. J., Princeton Univ. Press, p. 509-525.

Hill, M. L., and Dibblee, T. W., Jr., 1953, San Andreas, Big 

Pine, and Garlock faults, California a study of the 

character, history, and tectonic significance of their displacements: Geol. Soc. America Bull., v. 64, no. 4, p. 

443-458.

Hill, M. L., Carlson, S. A., and Dibblee, T. W., Jr., 1958, 

Stratigraphy of Cuyama Valley Caliente Range area, 

California: Am. Assoc. Petroleum Geologists Bull., v. 

42, no. 12, p. 2973-3000.

Huffman, O. F., 1970, Miocene and post-Miocene offset on 

the San Andreas fault in central California [abs.]: Geol. 

Soc. America Abs. with Programs, v. 2, no. 2, p. 104-105.

James, G. T, 1963, Paleontology and nonmarine stratigraphy 

of the Cuyama Valley badlands, California; Pt. 1, 

Geology, faunal interpretations, and systematic descriptions of Chiroptera, Insectivora, and Rodentia: California Univ. Pubs. Geol. Sci., v. 45,154 p.

Jennings, C. W., 1958, Geologic map of California, Olaf P. 

Jenkins edition, San Luis Obispo Sheet: California Div. 

Mines Map Sheet.

Johnson, H. R., 1909, Geology of the McKittrick-Sunset District, California [abs.]: Science, v. 30, p. 63-64.

Kleinpell, R. M., 1938, Miocene stratigraphy of California: 

Tulsa, Okla., Am. Assoc. Petroleum Geologists, 450 p.

Lawson, A. C., 1914, Description of the San Francisco district Tamalpais, San Francisco, Concord, San Mateo 

and Hayward quadrangles [California]: U.S. Geol. Survey Geol. Atlas, Folio 193.

Loel, Wayne, and Corey, W. H., 1932, The Vanqueros Formation, lower Miocene of California; Pt. 1, Paleontology: 

California Univ. Pubs., Dept. GeoL Bull, v, 22, no. 3, p. 

31-410.

Louderback, G. D., 1913, The Monterey series in California: 

California Univ. Pubs., Dept. Geol. Bull., v. 7, p. 177- 

214.

McMasters, J. H., 1947, Cymric oil field, Kern County, California, in Field trip guidebook, Am. Assoc. Petroleum

Geologists, Soc. Econ. Geophysicists, and Soc. Econ. 

Paleontologists and Mineralogists, Pacific Sees., Ann. 

Field Trip, 1947: p. 100-105.

Mallory, V. S., 1959, Lower Tertiary biostratigraphy of the 

California Coast Ranges: Tulsa, Okla., Am. Assoc. 

Petroleum Geologists, 416 p.

Marsh, O. T., 1960, Geology of the Orchard Peak area, California: California Div. Mines Spec. Rept. 62, 42 p.

Noble, E. B., 1940, Rio Bravo oil field, Kem County, California: Am. Assoc. Petroleum Geologists Bull., v. 24, no. 

7, p. 1330-1333.

Nomland, J. O., 1916, Fauna from the lower Pliocene at 

Jacalitos Creek and Waltham Canyon, Fresno County, 

California: California Univ. Pubs., Dept. Geology Bull., 

v. 9, p. 199-214.

 1917, The Etchegoin Pliocene of middle California: 

California Univ. Pubs., Dept. Geology Bull., v. 10, no. 

14, p. 201-202.

Pack, R. W., 1920, The Sunset-Midway oil field, California; 

Part 1, Geology and oil resources: U.S. Geol. Survey 

Prof. Paper 116,179 p.

Page, B. M., 1970, Sur-Nacimiento fault zone of California: 

Continental margin tectonics: Geol. Soc. America Bull., 

v. 81, p. 667-690.

Reed, R. D., 1933, Geology of California: Tulsa, Okla., Am. 

Assoc. Petroleum Geologists, 355 p.

Repenning, C. A., and Vedder, J. G., 1961, Continental vertebrates and their stratigraphic correlation with marine 

mollusks, eastern Caliente Range, California, in Short 

papers in the geologic and hydrologic sciences, 1961: 

U.S. Geol. Survey Prof. Paper 424-C, p. C235-C239.

Rose, R. L., and Colburn, I. P., 1963, Geology of the eastcentral part of the Priest Valley quadrangle, California, 

in Guidebook to geology of Salinas Valley and San 

Andreas fault, Am. Assoc. Petroleum Geologists and 

Soc. Econ. Paleontologists, Pacific Sees., Ann. Field 

Trip, 1963: p. 38-45.

San Joaquin Geological Society, 1959, Guidebook, field trip, 

Chico Martinez Creek area, California, May 9, 1959: 15 

p., geol. map.

Savage, D. E., 1957, Age of the Caliente Formation, Caliente 

Range, California [abs.]: Geol. Soc. America Bull., v. 

68, no. 12, pt. 2, p. 1845.

Savage, D. E., Downs, Theodore, and Poe, O. J., 1954, 

Cenozoic land life of southern California, pt. 6 in chap. 

3 of Jahns, R. H., ed., Geology of southern California: 

California Div. Mines Bull. 170, p. 43-58.

Schultz, J. R., 1938, A late Quaternary mammal fauna from 

the tar seeps of McKittrick, California: Carnegie Inst. 

Washington Pub. 487, p. 113-215.

Siegfus, S. S., 1939, Stratigraphic features of Reef Ridge 

Shale in southern California: Am. Assoc. Petroleum 

Geologists Bull, v. 3, no. 1, p. 24-44.

Simonson, R. R., and Krueger, M. L., 1942, Crocker Flat 

Landslide area, Temblor Range, California: Am. Assoc. 

Petroleum Geologists Bull., v. 26, no. 10, p. 1608-1631.

Smith, H. P., 1956, Foraminifera from the Wagonwheel 

Formation, Devils Den district, California: California 

Univ. Pubs. Geol. Sci., v. 32, p. 65-126.

Stewart, Ralph, 1946, Geology of Reef Ridge, Coalinga district, California: U.S. Geol. Survey Prof. Paper 205-C, 

p. 81-115 [1947].
REFERENCES CITED 45

Taliaferro, N. L., 1943, Geologic history and structure of the 

central Coast Ranges of California: California Div. 

Mines BulU 118, p. 119-162.

Thorup, R. R., 1943, Type locality of the Vaqueros Formation [California]: California Div. Mines Bull. 118, p. 

463-466.

Turner, D. L., 1970, Potassium-argon dating of Pacific 

Coast Miocene foraminiferal stages: Geol. Soc. America 

Spec, Paper 124, p. 91-129.

Van Couvering, Martin, and Alien, H. B., 1943, Devils Den 

oil field [California]: California Div. Mines Bull. 118, 

p. 496-501.

Vedder, J. G., 1970, Geologic map of the Wells Ranch and 

Elkhorn Hills quadrangles, San Luis Obispo and Kern 

Counties, California showing juxtaposed Cenozoic rocks 

along the San Andreas fault: U.S. Geol. Survey Misc. 

Geol. Inv. Map 1-585.

Vedder, J. G., and Brown, R. D., 1968, Structural and stratigraphic relations along the Nacimiento fault in the 

southern Santa Lucia Range and San Rafael Mountains, California, in Dickinson, W. R. and Grantz, 

Arthur, eds., Proceedings of conference on geologic problems of the San Andreas fault system: Stanford Univ. 

Pubs. Geol. Sci., v. 11, p. 243-258.

Vedder, J. G., and Repenning, C. A., 1965, Geologic map of 

the southeastern Caliente Range, San Luis Obispo 

County, California: U.S. Geol. Survey Oil and Gas Inv. 

Map OM-217.

Wagner, H. C., Bartow, J. A., Pierce, R. H., and Dibblee, T. 

W., Jr., 1973, Geologic sections across the San Andreas 

fault in the Carrizo Plain and the Temblor, Caliente, 

and La Panza Ranges and vicinity, California: U.S. 

Geol. Survey Misc. Geol. Inv. Map [in press].

Wahrhaftig, Clyde, and Birman, J. H., 1965, The Quaternary 

of the Pacific Mountain system in California, in Wright, 

H. E., and Frey, D. G., eds., The Quaternary of the 

United States A review volume for the 7th Congress 

of International Association for Quaternary research: 

Princeton, N. J., Princeton Univ. Press, p. 299-340.

Watts, W. L., 1897, Oil and gas yielding formations of Los 

Angeles, Ventura and Santa Barbara Counties, California: California State Min. Bur. Bull. 11, 94 p.

Weaver, C. E., chm., and others, 1944, Correlation of the 

marine Cenozoic formations of western North America 

[Chart 11]: Geol. Soc. America Bull., v. 55, no. 5, p. 

569-598.

White, R. T., 1938, Eocene Lodo formation and Cerros member of California [abs.]: Geol. Soc. America Proc. for 

1937, p. 256-257.

Wiedey, L. W., 1928, Notes on the Vaqueros and Temblor 

Formations of the California Miocene with descriptions 

of new species: San Diego Soc. Nat. History Trans., 

v. 5, no. 10, p. 95-182.

Williams, R. N., 1936, Recent developments in the North 

Belridge oil field [California]: California Oil Fields 

Summ. Operations, v. 21, no. 4, p. 5-16.

Wilmarth, M. G., 1938, Lexicon of geologic names of the 

United States (including Alaska): U.S. Geol. Survey 

Bull. 896, 2396 p.

Wood, H. E., chm., and others, 1941, Nomenclature and correlation of the North American continental Tertiary: 

Geol. Soc. America Bull., v. 52, no. 1, p. 1-48.

Woodring, W. P., Bramlette, M. N., and Kleinpell, R. M., 

1936, Miocene stratigraphy and paleontology of Palos 

Verdes Hills, California: Am. Assoc. Petroleum Geologists Bull., v. 20, no. 2, p. 125-159.

Woodring, W. P., Roundy, P. V., and Farnsworth, H. R.,. 

1932, Geology and oil resources of the Elk Hills, California (including Naval Petroleum Reserve No. 1): 

U.S. Geol. Survey Bull. 835, 82 p.

Woodring, W. P., Stewart, R. B., and Richards R. W., 1940, 

Geology of the Kettleman Hills oil field, California, stratigraphy, paleontology, and structure: U.S. Geol. Survey Prof. Paper 195, 170 p.

Young, Umberto, 1943, Republic area of the Midway-Sunset 

oil field [California]: California Div. Mines Bull. 118, 

p. 522-525.

0. S. GOVERNMENT PRINTING OFFICE : 1973 O - 495-417