0 3 04 0 4 3 0 3 7 k 1 7 e 1 l tl t a s t f 8 1 S k M t E ey …U. S. D E P A R T M E N T O F T H E...
1
U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 03-418 Prepared in cooperation with the CALIFORNIA GEOLOGICAL SURVEY PRELIMINARY GEOLOGIC MAP OF THE FONTANA 7.5' QUADRANGLE, SAN BERNARDINO AND RIVERSIDE COUNTIES, CALIFORNIA Base from U.S. Geological Survey 7.5' Fontana quadrangle, 1973 Polyconic projection 1 0 1 MILE 1 2 1 KILOMETER 0 .5 1 CONTOUR INTERVAL 20 FEET SCALE 1:24,000 GN MN DESCRIPTION OF MAP UNITS VERY YOUNG SURFICIAL DEPOSITS—Sediment recently transported and deposited in channels and washes, on surfaces of alluvial- fans and alluvial plains, and on hillslopes. Soil-profile development is non- existent. Includes: Artificial fill (late Holocene)—Uncompacted fill from mining operations and solid-waste disposal. South of Sunnyslope includes area of cut- and-fill. Includes levees along the Santa Ana River. At the Crestmore quarry area includes mix of Qaf and unconsolidated talus deposits Active alluvial-channel deposits (late Holocene)—Unconsolidated grayish sandy alluvium along Santa Ana River. Subject to reworking by stream flow YOUNG SURFICIAL DEPOSITS—Sedimentary units that are slightly consolidated to cemented and slightly to moderately dissected. Alluvial-fan deposits (Qyf series) typically have high coarse:fine clast ratios. Younger surficial units have upper surfaces that are capped by slight to moderately developed pedogenic-soil profiles (A/C to A/AC/BcambricCox profiles). Includes: Young alluvial-fan deposits of Etiwanda Creek (Holocene and late Pleistocene)—Unconsolidated grayish cobbly alluvium of East Etiwanda Creek fan. Restricted to eastern part of the East Etiwanda Creek fan, 1 km east of Bloomington Young alluvial-fan deposits of Lytle Creek (Holocene and late Pleistocene)—Unconsolidated, gray, cobbly and bouldery alluvium of Lytle Creek fan. Relatively fine-grained (pebbly and cobbly) in southern extent; becomes coarser grained (cobbly and bouldery) northward. Forms broad channels west and north of Crestmore. Includes: Young alluvial-fan deposits of Lytle Creek, Unit 1 (early Holocene and late Pleistocene)—Unconsolidated alluvial-fan deposits. Consists of gravel, sand, and silt Young alluvial-channel deposits (Holocene and late Pleistocene)—Unconsolidated, gray, sandy alluvium along Santa Ana River, and headward part of broad channel along northwestern Jurupa Mountains. Includes: Young alluvial-channel deposits, Unit 1 (early Holocene and late Pleistocene)—Unconsolidated, gray, sandy alluvium. Older fluvial deposit of Santa Ana River; older and slightly elevated above Qya Eolian deposits (Holocene and late Pleistocene)—Unconsolidated, gray to tan, massive, fine-grained sand forming stabilized dunes. May include some deposits of Pleistocene age OLD SURFICIAL DEPOSITS—Sedimentary units that are moderately consolidated and slightly to moderately dissected. Older surficial deposits have upper surfaces that are capped by moderately to well-developed pedogenic soils (A/AB/B/Cox profiles and Bt horizons as much as 1 to 2 m thick and maximum hues in the range of 10YR 5/4 and 6/4 through 7.5YR 6/4 to 4/4 and mature Bt horizons reaching 5YR 5/6). Includes: Old alluvial-fan deposits (late to middle Pleistocene)—Reddish brown, gravel and sand alluvial-fan deposits; indurated, commonly slightly dissected. In places includes thin alluvial-fan deposits of Holocene age. Includes: Old alluvial-fan deposits, Unit 3 (late to middle Pleistocene)—Unconsolidated, tan, cobbly and bouldery alluvium. Occurs as slightly raised deposits through younger Lytle Creek fan (Qyfl). May include some deposits of Holocene age Old alluvial-fan deposits, Unit 2 (late to middle Pleistocene)—Unconsolidated, tan, cobbly and bouldery alluvium of Lytle Creek fan. Slightly older than Qof 3 Old alluvial-fan deposits, Unit 1 (late to middle Pleistocene)—Mainly indurated, tan to brown, sandy to pebbly and cobbly, clay-bearing older alluvium. Forms extensive deposits on south side of Jurupa Mountains. Near Jurupa Mountains includes consolidated conglomeratic deposits. Locally underlain by unconsolidated gray cobbly alluvium VERY OLD SURFICIAL DEPOSITS—Sediments that are slightly to well consolidated to indurated, and moderately to well dissected. Upper surfaces are capped by moderate to well developed pedogenic soils (A/AB/B/Cox profiles having Bt horizons as much as 2 to 3 m thick and maximum hues in the range 7.5YR 6/4 and 4/4 to 2.5YR 5/6) Very old alluvial-fan deposits (middle to early Pleistocene)—Patches of well-indurated, brown, pebbly and cobbly, clay-bearing alluvium perched on and near summit areas of Jurupa Mountains, May be remnants of previously extensive deposit Generic Cretaceous granitic rocks of the Peninsular Ranges batholith Granitic dikes, undifferentiated (Cretaceous)—Coarse-grained granite to pegmatitic-textured, off-white biotite granite dikes. Pegmatite dikes contain accessory muscovite, garnet and tourmaline. Fairly abundant north of Rubidoux and Glen Avon Granodiorite (Cretaceous)—Medium- to coarse-grained, equigranular to porphyritic, heterogeneous biotite granodiorite and lesser amounts of monzogranite and tonalite. Contains locally abundant inclusions and schist septa. Includes: Granodiorite, Unit 1 (Cretaceous)—Medium- to coarse-grained, equigranular to porphyritic, heterogeneous granodiorite and lesser amounts of monzogranite and tonalite. Contains locally abundant inclusions and schist septa Tonalite (Cretaceous)—Relatively uniform, medium-to coarse-grained equigranular gray biotite-hornblende tonalite. Contains widespread and locally abundant dark inclusions Tonalite, Unit 1 (Cretaceous)—Homogeneous biotite hornblende tonalite and hornblende quartz diorite and lesser amounts of hornblende diorite and granodiorite. Contains widespread and locally abundant dark inclusions Tonalite and granodiorite, undifferentiated (Cretaceous)— Undifferentiated intermixed biotite-hornblende tonalite and biotite granodiorite Diorite (Cretaceous)—Mainly coarse-grained equigranular dark-gray hornblende diorite Diorite and tonalite, undifferentiated (Cretaceous)—Undifferentiated intermixed hornblende diorite and biotite-hornblende tonalite Gabbro (Cretaceous)—Mainly coarse-grained to locally pegmatitic black hornblende gabbro End rocks of Peninsular Ranges batholith Schist (Paleozoic)—Mainly interlayered biotite schist and quartzite. Layers typically one to several centimeters thick. Locally contains discontinuous calc-silicate-rich amphibolite layers Marble (Paleozoic)—Mainly coarse-grained nearly white marble and included masses of calc-silicate rock Amphibolite (Paleozoic)—Coarse-grained, crudely foliated, black amphibolite Intermixed heterogenous tonalite and schist (Cretaceous and Paleozoic)—Intermixed biotite-hornblende tonalite and biotite-quartz schist. Restricted to north-central part of Jurupa Mountains Intermixed tonalite and marble (Cretaceous and Paleozoic)—Marble intruded by heterogeneous biotite-hornblende tonalite. Restricted to east end of Jurupa Mountains (Jensen Quarry area) Intermixed tonalite, marble and schist (Cretaceous and Paleozoic)—Intermixed biotite-hornblende tonalite and coarse grained marble containing lesser amounts of biotite-quartz schist. Restricted to Crestmore area GEOLOGIC SUMMARY The Fontana 7.5' quadrangle is located in the northern part of the Perris Block (English, 1926, Woodford, and others, 1971), a rectangular shaped and relatively tectonically stable structural block located between the San Jacinto and Elsinore Fault zones at the north end of the Peninsular Ranges Provinces (Jahns, 1954). Included in the southern part of the quadrangle are the Jurupa Mountains, that along with rocks exposed in the San Bernardino South 7.5' quadrangle to the east, are underlain by exposures of the northernmost Peninsular Ranges province basement rocks. The oldest rocks are a sequence of amphibolite grade metamorphic rocks consisting of predominantly biotite-quartz schist and lesser amounts of quartzite, marble, and amphibolite. The marble forms relatively thick layers, most of which have been quarried, mainly for manufacturing of cement. Pyroxene hornfels facies skarn occurs along contact zones between marble and intrusive granitic rocks. Major marble quarries include the Crestmore quarries at the eastern part of the quadrangle and the Jensen quarry at the eastern end of the Jurupa Mountains; smaller quarries are the Henshaw quarry located between the Crestmore quarries and the Jensen Quarry, and the Glen Avon Quarry located in the western part of the Jurupa Mountains. Much of the marble at the Crestmore quarries has a characteristic blue color. The Crestmore quarries are known worldwide for the large number of rare minerals found in the contact metamorphic rocks (about 150 mineral species, e.g., Murdoch and Webb, 1966). Most of the unusual minerals occur in a metasomatic zone between marble and a monzogranite intrusive in the Commercial Quarry (e.g., Burnham, 1959, Woodford and others, 1941). Based upon the abundance of marble in the section, these metasedimentary rocks are considered to be of Paleozoic age. Intruding the metamorphic rocks are Cretaceous-age granitic rocks, the northern part of the Peninsular Ranges batholith. These batholithic rocks range in composition from gabbro to granitic pegmatite dikes. Biotite-hornblende tonalite is the most abundant granitic rock, but there is a large biotite granodiorite body located near the central part of the Jurupa Mountains. Emplacement age of the tonalite, based on U/Pb analyses of zircon, is 104 +/- 0.4 Ma (W.R. Premo, Written Com., 2003). Sr/Rb isochron whole rock age is 117.6 +/- 6 Ma (R.W. Kistler, Written Com., 2000). Granodiorite (Kgd) gave a zircon U/Pb age of 108 +/- 6 Ma (W.R. Premo, Written Com., 2003). Tonalite and granodiorite commonly have two planar fabrics, a planar fabric oriented northwest that is typical Peninsular Range Batholith and one that is atypical striking east and northeast; both planar fabrics are produced by oriented hornblende and biotite and ellipsoidal to pancake-shaped mafic inclusions. East and northeast oriented inclusions are generally noticeably more attenuated than the northwest oriented inclusions. Commonly a single outcrop includes both fabric planes; where discernible the northwest striking fabric is older than the east and northeast oriented fabric. The granitic rocks are some of the closest granitic rocks to the Los Angeles Metropolitan area that can be used for construction purposes. As such, the tonalite and granodiorite have been extensively quarried for the construction of breakwaters and a variety of other engineering projects. A major quarrying operation was located at the north central part of the Jurupa Mountains at Declezville where a rail line spur was constructed for transportation of tonalite. Another large quarry is located in the hills immediately east of the Jurupa Mountains. Currently the only active quarry is the Stringfellow quarries developed in granodiorite and located in the south central part of the Jurupa Mountains. The northern half of the quadrangle is covered by unconsolidated boulder and cobble-bearing alluvium of the distal part of the Lytle Creek fan that emanates from the San Gabriel Mountains north of the quadrangle. An older alluvial-fan deposit derived from the eastern San Gabriel Mountains once covered the Jurupa Mountains; cobbles of eastern San Gabriel Mountains rocks, remnants of this now vanished fan, occur along ridge tops of the Jurupa Mountains and the hill to the east of the mountains (Morton and Matti, 1989). Pleistocene alluvial-fan deposits flank the south side of the Jurupa Mountains. Most of these deposits are well indurated, brown, sandy deposits containing cobble deposits near the south side of the mountains; clasts are locally derived from the Jurupa Mountains. The active channel of the Santa Ana River is located in the southeast corner of the quadrangle. REFERENCES Burnham, C.W., 1959, Contact metamorphism of magnesium limestone at Crestmore, California: Geological Society of America Bulletin, v. 70, p. 879-970. English, W.A., 1926, Geology and oil resources of the Puente Hills region, California: U.S. Geological Survey Bulletin 768, 110 p. Jahns, R.H., 1954, Geology of the Peninsular Ranges Province, southern California and Baja California, in Jahns, R.H., ed., Geology of southern California: California Division of Mines and Geology Bulletin 170, chapter 2, p. 29-52. Morton, D.M., 1978, Geologic map of the Fontana 7.5' quadrangle, San Bernardino and Riverside Counties, California: U.S. Geological Survey Open-File Report 78-19, scale, 1:24,000. Morton, D.M., and Matti, J.C., 1989, A vanished late Pliocene to early Pleistocene alluvial-fan complex in the northern Perris Block, southern California, in Colburn, I.P., and Minch, J., eds., Conglomerates in basin analysis: A symposium dedicated to A.O. Woodford: Pacific Section Society of Economic Paleontologists and Mineralogists, v. 62, p. 73-80. Murdoch, J., and Webb, R.W., 1966, Minerals of California: California Division of Mines and Geology Bulletin 189. Streckeisen, A.L., 1973, Plutonic rocks—Classification and nomenclature recommended by the IUGA Subcommission on Systematics of Igneous Rocks: Geotimes, v. 18, p. 26-30. Woodford, A.O., Crippen, R.A., and Garner, K.B., 1941, Section across Commercial quarry, Crestmore, California: American Mineralogist, v. 26, p. 351-381. Woodford, A.O., Shelton, J.S., Doehring, D.O., and Morton, R.K., 1971, Pliocene-Pleistocene history of the Perris Block, southern California: Geological Society of America Bulletin, v. 82, p. 3421-3448. Version 1.0 By D. M. Morton 1 Digital preparation by Kelly R. Bovard 1 Classification of plutonic rock types (from IUGA, 1973, and Streckeisen, 1973). A, alkali feldspar; P, plagioclase feldspar; Q, quartz. Quartz Syenite Quartz Monzonite Quartz Monzodiorite Syenite Monzonite Monzodiorite Granite Alkali-feldspar Granite Tonalite Diorite Syenogranite Granodiorite Monzogranite Quartz Diorite 90 65 35 10 5 20 60 Q Q A P 60 20 5 60 117 o 30' 34 o 7' 30" 117 o 30' 34 o 00' On some SCAMP geologic map plots, including the Fontana 7.5' quadrangle, characteristic grain size information is displayed using subscripted alpha characters (e.g., Qyf g , Qov a , after the unit label), where the characters conform to the following definitions: a - arenaceous; sand or sand bearing (very coarse sand through very fine sand) b - boulders or containing boulders (>25mm) g - gravel or containing gravel (cobble through granule gravel) s - silt or silty c - clay or clay bearing m- marl p - peat Where a unit label has more than one subscripted character, in all cases, the first character modifies the second (e.g., Qyf ag indicates arenaceous gravel). In the Description of Map Units, the Ma following U/Pb ages has an attached subscript; Ma id for isotope dilution analyses, and Ma ip for ion probe analyses. 15 o 1 U.S. Geological Survey Department of Earth Sciences University of California Riverside, CA 92521 34 o 00' 117 o 22' 30'' 117 o 22' 30'' 34 o 7' 30" LOCATION MAP SURROUNDING 7.5' QUADRANGLES Corona North Fontana 7.5' Riverside West Riverside East San Bernardino South Guasti Cucamonga Peak Devore San Bernardino North This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, firm, or product names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. This map was printed on an electronic plotter directly from digital files. Dimensional calibration may vary between electronic plotters and between X and Y directions on the same plotter, and paper may change size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map. Digital files available on World Wide Web at http://geopubs.wr.usgs.gov/ open-file/of03-418/ Geology mapped by D.M. Morton; 1977-78, 1990-99. Qaf Qvof Qa Qyfl Qyfe Qof 3 Qof 2 Qof 1 Kg Kgd Kt Kt 1 Kgdt Kd Kdqd Kgb |s |m |a Kt|s Kt|m Kt|ms Qya Qyfl 1 Qye Kgd 1 Qya 1 Contact—Solid where located within ±15 meters; dashed where located within ±30 meters Kg—Granitic dikes 70 Strike and dip of igneous foliation Inclined Vertical Strike and dip of metamorphic foliation Inclined Vertical Strike and dip of secondary foliation in igneous rocks Inclined Vertical Bearing and plunge of igneous lineations Inclined Bearing and plunge of metamorphic lineations Inclined 70 50 20 55 H o l c o m b C r e e k Shay Mtn White Mtn Rabbit Dry Lake Devore M i l l C r e e k S a n t a A n a R i v e r Sa n Tim o t e o W a s h S a n B e r n a r d i n o B a s i n Arrowhead Peak Butler Peak Arrowhead Lake Rocks of the Peninsular Ranges assemblage. South of the quadrangle, offset Peninsular Ranges rocks occur east of the San S A N G A B R I E L F A U L T Cogswell Reservoir S a n Ga b r i e l R i ve r S a n J o s e H i l l s San Bernardino Map of San Bernardino 30' X 60' quadrangle showing the location of the Fontana 7.5' quadrangle. Colored areas define structural assemblages. Approximate locations of most faults having large displacements or lengths are shown. Inferred boundary between Peninsular Ranges and San Gabriel Mountains assemblages is hidden beneath thick Quaternary deposits, and its location and character are highly speculative. Town or geographic feature; Mountain Peak. SAN BERNARDINO MOUNTAINS ASSEMBLAGE 0 10 5 15 Km 34° 00' 118° 00' 34° 30' 118° 00' 34° 30' 117° 00' 34° 00' 117° 00' D a y C y n Cucamonga Peak Telegraph Peak C a jon C y n Vincent Thrust Ly t l e C r e e k Cajon Pass Lake Gregory M o j a v e Silverwood Lake O R D M T N S M O J A V E D E S E R T Apple Valley Burnt Flats R i v e r Hesperia A n t e l o p e V a l l e y S A N JA C I NTO FAU LT Z ON E Riverside P E N I N S U L A R R A N G E S A SSE M B L A G E M I L L CR E E K F AU L T SAN ANDRE AS F A U LT Z O N E Y uc a i p a V a l l e Lone Pine C y n S h e e p C r e e k Phelan Wrightwood D e e p C r e e k Azusa Glendora P U N C H B O W L F A U L T Waterman Mtn Juniper Hills Pine Mtn La Verne L it t l e Pomona Ontario Upland Rancho Cucamonga S A N G A B R I E L M O U N T A I N S ASSEMBLAGE Crystal Lake S a n J o s e F a u lt S I E R R A M A D R E F A U L T Z O N E C U C A M O N G A F A U L T Z O N E P ue nt e H il ls P ue nt e H ill s I n f e r r e d b o un d a r y b e t w e e n P e n in s ula r R a n g e s a n d S an G a briel M o u n t a in s b lo c ks S AN ANDRE AS FAULT M e s c a l C r e e k R oc k C r e e k S an A n t o n i o C y n GLEN H E L E N FAULT Jurupa Mountains Fontana Rialto Rocks of the San Gabriel Mountains assemblage. Includes basement (mostly concealed by Quaternary deposits) that is offset by the San Jacinto Fault Rocks of the San Bernardino Mountains assemblage. Includes basement (mostly concealed by Quaternary deposits) of the Mojave Desert, which is similar to San Bernardino Mountains basement Rocks bounded by Mission Creek segment of San of the Andreas Fault Zone, and the Mill Creek Fault O a k G l e n C r e e k Sand Cyn W a s h CL E G H OR N F A UL T D E V I L C A N Y O N F A U L T SA N TA A NA CA N Y O N F AU LT ZO NE GRANITE MTNS CORRELATION OF MAP UNITS QUATERNARY CENOZOIC Holocene Pleistocene CRETACEOUS MESOZOIC Qaf Qyfe Qyfl Qya Qye Qvof Qof 3 Qof 2 Qof 1 Qyfl 1 Qya 1 Qa PALEOZOIC Kg Kgd Kt Kgdt Kd Kdqd Kgb Kgd 1 Kt 1 |s |m |a Kt|s Kt|m Kt|ms Generic Cretaceous rocks of the Peninsular Ranges batholith Fontana 7.5' Quadrangle
Transcript of 0 3 04 0 4 3 0 3 7 k 1 7 e 1 l tl t a s t f 8 1 S k M t E ey …U. S. D E P A R T M E N T O F T H E...
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in c
hann
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and
was
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on
surf
aces
of
allu
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nd a
lluvi
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lain
s, a
nd o
n hi
llslo
pes.
Soi
l-pr
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dev
elop
men
t is
non-
exis
tent
. In
clud
es:
Art
ific
ial f
ill (
late
Hol
ocen
e)—
Unc
ompa
cted
fill
fro
m m
inin
g op
erat
ions
an
d so
lid-w
aste
dis
posa
l. S
outh
of
Sunn
yslo
pe i
nclu
des
area
of
cut-
and-
fill.
In
clud
es l
evee
s al
ong
the
Sant
a A
na R
iver
. A
t th
e C
rest
mor
e qu
arry
are
a in
clud
es m
ix o
f Q
af a
nd u
ncon
solid
ated
talu
s de
posi
tsA
ctiv
e al
luvi
al-c
han
nel
d
epos
its
(lat
e H
oloc
ene)
—U
ncon
soli
date
d gr
ayis
h sa
ndy
allu
vium
alo
ng S
anta
Ana
Riv
er.
Sub
ject
to
rew
orki
ng
by s
trea
m f
low
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UN
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UR
FIC
IAL
DE
PO
SIT
S—Se
dim
enta
ry u
nits
tha
t ar
e sl
ight
ly
cons
olid
ated
to c
emen
ted
and
slig
htly
to m
oder
atel
y di
ssec
ted.
Allu
vial
-fan
de
posi
ts (
Qyf
ser
ies)
typ
ical
ly h
ave
high
coa
rse:
fine
cla
st r
atio
s.
You
nger
su
rfic
ial
units
hav
e up
per
surf
aces
tha
t ar
e ca
pped
by
slig
ht t
o m
oder
atel
y de
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ped
pedo
geni
c-so
il pr
ofile
s (A
/C t
o A
/AC
/Bca
mbr
icC
ox p
rofi
les)
.
Incl
udes
:Y
oung
allu
vial
-fan
dep
osit
s of
Eti
wan
da C
reek
(H
oloc
ene
and
late
P
leis
toce
ne)
—U
ncon
soli
date
d gr
ayis
h co
bbly
al
luvi
um
of
Eas
t E
tiwan
da C
reek
fan
. R
estr
icte
d to
eas
tern
par
t of
the
Eas
t E
tiwan
da
Cre
ek f
an, 1
km
eas
t of
Blo
omin
gton
You
ng
allu
vial
-fan
d
epos
its
of
Lyt
le
Cre
ek
(Hol
ocen
e an
d
late
P
leis
toce
ne)—
Unc
onso
lidat
ed,
gray
, co
bbly
and
bou
lder
y al
luvi
um o
f L
ytle
Cre
ek f
an.
Rel
ativ
ely
fine
-gra
ined
(pe
bbly
and
cob
bly)
in
sout
hern
ext
ent;
be
com
es c
oars
er g
rain
ed (
cobb
ly a
nd b
ould
ery)
no
rthw
ard.
F
orm
s br
oad
chan
nels
wes
t an
d no
rth
of C
rest
mor
e.
Incl
udes
:Y
oung
allu
vial
-fan
dep
osit
s of
Lyt
le C
reek
, U
nit
1 (e
arly
Hol
ocen
e an
d la
te P
leis
toce
ne)—
Unc
onso
lidat
ed a
lluvi
al-f
an d
epos
its.
Con
sist
s of
gra
vel,
sand
, and
silt
You
ng
allu
vial
-ch
ann
el
dep
osit
s (H
oloc
ene
and
la
te
Ple
isto
cene
)—U
ncon
solid
ated
, gr
ay,
sand
y al
luvi
um a
long
San
ta A
na
Riv
er,
and
head
war
d pa
rt o
f br
oad
chan
nel
alon
g no
rthw
este
rn J
urup
a M
ount
ains
. In
clud
es:
You
ng a
lluvi
al-c
hann
el d
epos
its,
Uni
t 1
(ear
ly H
oloc
ene
and
late
P
leis
toce
ne)—
Unc
onso
lidat
ed,
gray
, sa
ndy
allu
vium
. O
lder
flu
vial
de
posi
t of
Sant
a A
na R
iver
; old
er a
nd s
light
ly e
leva
ted
abov
e Q
ya
Eol
ian
depo
sits
(H
oloc
ene
and
late
Ple
isto
cene
)—U
ncon
solid
ated
, gra
y to
tan
, m
assi
ve,
fine
-gra
ined
san
d fo
rmin
g st
abil
ized
dun
es.
May
in
clud
e so
me
depo
sits
of
Plei
stoc
ene
age
OL
D S
UR
FIC
IAL
DE
PO
SIT
S—Se
dim
enta
ry u
nits
tha
t ar
e m
oder
atel
y co
nsol
idat
ed a
nd s
light
ly t
o m
oder
atel
y di
ssec
ted.
O
lder
sur
fici
al d
epos
its
have
upp
er s
urfa
ces
that
are
cap
ped
by m
oder
atel
y to
wel
l-de
velo
ped
pedo
geni
c so
ils (
A/A
B/B
/Cox
pro
file
s an
d B
t hor
izon
s as
muc
h as
1 to
2 m
th
ick
and
max
imum
hue
s in
the
ran
ge o
f 10
YR
5/4
and
6/4
thr
ough
7.5
YR
6/
4 to
4/4
and
mat
ure
Bt h
oriz
ons
reac
hing
5Y
R 5
/6).
Inc
lude
s:O
ld a
lluvi
al-f
an d
epos
its
(lat
e to
mid
dle
Ple
isto
cene
)—R
eddi
sh b
row
n,
grav
el a
nd s
and
allu
vial
-fan
dep
osits
; in
dura
ted,
com
mon
ly s
light
ly
diss
ecte
d.
In p
lace
s in
clud
es t
hin
allu
vial
-fan
dep
osits
of
Hol
ocen
e ag
e. I
nclu
des:
Old
al
luvi
al-f
an
dep
osit
s,
Un
it
3 (l
ate
to
mid
dle
P
leis
toce
ne)—
Unc
onso
lida
ted,
tan
, co
bbly
and
bou
lder
y al
luvi
um.
O
ccur
s as
slig
htly
rai
sed
depo
sits
thr
ough
you
nger
Lyt
le C
reek
fan
(Q
yfl).
May
incl
ude
som
e de
posi
ts o
f H
oloc
ene
age
Old
al
luvi
al-f
an
dep
osit
s,
Un
it
2 (l
ate
to
mid
dle
P
leis
toce
ne)—
Unc
onso
lidat
ed,
tan,
cob
bly
and
boul
dery
allu
vium
of
Lyt
le C
reek
fan
. Sl
ight
ly o
lder
than
Qof
3O
ld
allu
vial
-fan
d
epos
its,
U
nit
1
(lat
e to
m
idd
le
Ple
isto
cene
)—M
ainl
y in
dura
ted,
tan
to
brow
n, s
andy
to
pebb
ly a
nd
cobb
ly,
clay
-bea
ring
old
er a
lluv
ium
. F
orm
s ex
tens
ive
depo
sits
on
sout
h si
de o
f Ju
rupa
Mou
ntai
ns.
Nea
r Ju
rupa
Mou
ntai
ns i
nclu
des
cons
olid
ated
co
nglo
mer
atic
de
posi
ts.
L
ocal
ly
unde
rlai
n by
un
cons
olid
ated
gra
y co
bbly
allu
vium
VE
RY
OL
D S
UR
FIC
IAL
DE
PO
SIT
S—Se
dim
ents
tha
t ar
e sl
ight
ly t
o w
ell
cons
olid
ated
to
indu
rate
d, a
nd m
oder
atel
y to
wel
l di
ssec
ted.
U
pper
su
rfac
es
are
capp
ed
by
mod
erat
e to
w
ell
deve
lope
d pe
doge
nic
soil
s (A
/AB
/B/C
ox p
rofi
les
havi
ng B
t ho
rizo
ns a
s m
uch
as 2
to
3 m
thi
ck a
nd
max
imum
hue
s in
the
rang
e 7.
5YR
6/4
and
4/4
to 2
.5Y
R 5
/6)
Ver
y ol
d al
luvi
al-f
an d
epos
its
(mid
dle
to e
arly
Ple
isto
cene
)—Pa
tche
s of
wel
l-in
dura
ted,
bro
wn,
peb
bly
and
cobb
ly,
clay
-bea
ring
allu
vium
pe
rche
d on
and
nea
r su
mm
it ar
eas
of J
urup
a M
ount
ains
, M
ay b
e re
mna
nts
of p
revi
ousl
y ex
tens
ive
depo
sit
Gen
eric
Cre
tace
ous
gran
itic
rock
s of
the
Pen
insu
lar
Ran
ges
bath
olith
Gra
niti
c di
kes,
und
iffe
rent
iate
d (C
reta
ceou
s)—
Coa
rse-
grai
ned
gran
ite t
o pe
gmat
itic-
text
ured
, of
f-w
hite
bio
tite
gran
ite d
ikes
. P
egm
atite
dik
es
cont
ain
acce
ssor
y m
usco
vite
, ga
rnet
and
tou
rmal
ine.
Fa
irly
abu
ndan
t no
rth
of R
ubid
oux
and
Gle
n A
von
Gra
nodi
orit
e (C
reta
ceou
s)—
Med
ium
- to
coa
rse-
grai
ned,
equ
igra
nula
r to
po
rphy
ritic
, he
tero
gene
ous
biot
ite g
rano
dior
ite a
nd l
esse
r am
ount
s of
m
onzo
gran
ite a
nd t
onal
ite.
Con
tain
s lo
cally
abu
ndan
t in
clus
ions
and
sc
hist
sep
ta.
Incl
udes
:G
ran
odio
rite
, U
nit
1
(Cre
tace
ous)
—M
ediu
m-
to
coar
se-g
rain
ed,
equi
gran
ular
to
porp
hyri
tic,
het
erog
eneo
us g
rano
dior
ite
and
less
er
amou
nts
of m
onzo
gran
ite
and
tona
lite
. C
onta
ins
loca
lly
abun
dant
in
clus
ions
and
sch
ist s
epta
Ton
alit
e (C
reta
ceou
s)—
Rel
ativ
ely
unif
orm
, m
ediu
m-t
o co
arse
-gra
ined
eq
uigr
anul
ar g
ray
biot
ite-h
ornb
lend
e to
nalit
e. C
onta
ins
wid
espr
ead
and
loca
lly a
bund
ant d
ark
incl
usio
nsT
onal
ite,
U
nit
1
(Cre
tace
ous)
—H
omog
eneo
us
biot
ite
horn
blen
de
tona
lite
and
horn
blen
de q
uart
z di
orite
and
less
er a
mou
nts
of h
ornb
lend
e di
orite
and
gra
nodi
orite
. C
onta
ins
wid
espr
ead
and
loca
lly a
bund
ant
dark
incl
usio
nsT
onal
ite
and
gr
anod
iori
te,
un
dif
fere
nti
ated
(C
reta
ceou
s)—
U
ndif
fere
ntia
ted
inte
rmix
ed b
ioti
te-h
ornb
lend
e to
nali
te a
nd b
ioti
te
gran
odio
rite
Dio
rite
(C
reta
ceou
s)—
Mai
nly
coar
se-g
rain
ed
equi
gran
ular
da
rk-g
ray
horn
blen
de d
iori
teD
iori
te a
nd t
onal
ite,
und
iffe
rent
iate
d (C
reta
ceou
s)—
Und
iffe
rent
iate
d in
term
ixed
hor
nble
nde
dior
ite a
nd b
iotit
e-ho
rnbl
ende
tona
lite
Gab
bro
(Cre
tace
ous)
—M
ainl
y co
arse
-gra
ined
to
loca
lly p
egm
atiti
c bl
ack
horn
blen
de g
abbr
o
End
roc
ks o
f P
enin
sula
r R
ange
s ba
thol
ith
Sch
ist
(Pal
eozo
ic)—
Mai
nly
inte
rlay
ered
bi
otit
e sc
hist
an
d qu
artz
ite.
L
ayer
s ty
pica
lly o
ne t
o se
vera
l ce
ntim
eter
s th
ick.
L
ocal
ly c
onta
ins
disc
ontin
uous
cal
c-si
licat
e-ri
ch a
mph
ibol
ite la
yers
Mar
ble
(P
aleo
zoic
)—M
ainl
y co
arse
-gra
ined
nea
rly
whi
te m
arbl
e an
d in
clud
ed m
asse
s of
cal
c-si
licat
e ro
ckA
mp
hib
olit
e (P
aleo
zoic
)—C
oars
e-gr
aine
d,
crud
ely
fo
liat
ed,
blac
k am
phib
olite
Inte
rmix
ed
het
erog
enou
s to
nal
ite
and
sc
his
t (C
reta
ceou
s
and
P
aleo
zoic
)—In
term
ixed
bio
tite-
horn
blen
de t
onal
ite a
nd b
iotit
e-qu
artz
sc
hist
. R
estr
icte
d to
nor
th-c
entr
al p
art o
f Ju
rupa
Mou
ntai
nsIn
term
ixed
ton
alit
e an
d m
arbl
e (C
reta
ceou
s an
d P
aleo
zoic
)—M
arbl
e in
trud
ed b
y he
tero
gene
ous
biot
ite-h
ornb
lend
e to
nalit
e.
Res
tric
ted
to
east
end
of
Juru
pa M
ount
ains
(Je
nsen
Qua
rry
area
)In
term
ixed
to
nal
ite,
m
arb
le
and
sc
his
t (C
reta
ceou
s an
d
Pal
eozo
ic)—
Inte
rmix
ed
biot
ite-h
ornb
lend
e to
nalit
e an
d co
arse
gra
ined
m
arbl
e co
ntai
ning
less
er a
mou
nts
of b
iotit
e-qu
artz
sch
ist.
Res
tric
ted
to
Cre
stm
ore
area
GE
OL
OG
IC S
UM
MA
RY
The
Fon
tana
7.5
' qua
dran
gle
is lo
cate
d in
the
nort
hern
par
t of
the
Per
ris
Blo
ck
(Eng
lish
, 19
26,
Woo
dfor
d,
and
othe
rs,
1971
),
a re
ctan
gula
r sh
aped
and
rel
ativ
ely
tect
onic
ally
sta
ble
stru
ctur
al b
lock
lo
cate
d be
twee
n th
e Sa
n Ja
cint
o an
d E
lsin
ore
Faul
t zon
es a
t the
nor
th
end
of t
he P
enin
sula
r R
ange
s Pr
ovin
ces
(Jah
ns,
1954
).
Incl
uded
in
the
sout
hern
par
t of
the
qua
dran
gle
are
the
Juru
pa M
ount
ains
, th
at
alon
g w
ith
rock
s ex
pose
d in
th
e S
an
Ber
nard
ino
Sou
th
7.5'
qu
adra
ngle
to
th
e ea
st,
are
unde
rlai
n by
ex
posu
res
of
the
nort
hern
mos
t P
enin
sula
r R
ange
s pr
ovin
ce b
asem
ent
rock
s.
The
ol
dest
roc
ks a
re a
seq
uenc
e of
am
phib
olite
gra
de m
etam
orph
ic r
ocks
co
nsis
ting
of p
redo
min
antly
bio
tite-
quar
tz s
chis
t an
d le
sser
am
ount
s of
qua
rtzi
te,
mar
ble,
and
am
phib
olite
. T
he m
arbl
e fo
rms
rela
tivel
y th
ick
laye
rs,
mos
t of
w
hich
ha
ve
been
qu
arri
ed,
mai
nly
for
man
ufac
turi
ng o
f ce
men
t. Py
roxe
ne h
ornf
els
faci
es s
karn
occ
urs
alon
g co
ntac
t zo
nes
betw
een
mar
ble
and
intr
usiv
e gr
aniti
c ro
cks.
M
ajor
mar
ble
quar
ries
inc
lude
the
Cre
stm
ore
quar
ries
at
the
east
ern
part
of
the
quad
rang
le a
nd th
e Je
nsen
qua
rry
at th
e ea
ster
n en
d of
the
Juru
pa M
ount
ains
; sm
alle
r qu
arri
es a
re t
he H
ensh
aw q
uarr
y lo
cate
d be
twee
n th
e C
rest
mor
e qu
arri
es a
nd th
e Je
nsen
Qua
rry,
and
the
Gle
n A
von
Qua
rry
loca
ted
in t
he w
este
rn p
art
of t
he J
urup
a M
ount
ains
. M
uch
of t
he m
arbl
e at
the
Cre
stm
ore
quar
ries
has
a c
hara
cter
istic
bl
ue c
olor
. T
he C
rest
mor
e qu
arri
es a
re k
now
n w
orld
wid
e fo
r th
e la
rge
num
ber
of r
are
min
eral
s fo
und
in t
he c
onta
ct m
etam
orph
ic
rock
s (a
bout
150
min
eral
spe
cies
, e.
g.,
Mur
doch
and
Web
b, 1
966)
.
Mos
t of
the
unu
sual
min
eral
s oc
cur
in a
met
asom
atic
zon
e be
twee
n m
arbl
e an
d a
mon
zogr
anite
intr
usiv
e in
the
Com
mer
cial
Qua
rry
(e.g
., B
urnh
am,
1959
, W
oodf
ord
and
othe
rs,
1941
).
Bas
ed u
pon
the
abun
danc
e of
mar
ble
in th
e se
ctio
n, th
ese
met
ased
imen
tary
roc
ks a
re
cons
ider
ed to
be
of P
aleo
zoic
age
.In
trud
ing
the
met
amor
phic
roc
ks a
re C
reta
ceou
s-ag
e gr
aniti
c ro
cks,
the
nor
ther
n pa
rt o
f th
e Pe
nins
ular
Ran
ges
bath
olith
. T
hese
ba
thol
ithi
c ro
cks
rang
e in
com
posi
tion
fro
m g
abbr
o to
gra
niti
c pe
gmat
ite d
ikes
. B
iotit
e-ho
rnbl
ende
ton
alite
is
the
mos
t ab
unda
nt
gran
itic
rock
, bu
t th
ere
is a
lar
ge b
iotit
e gr
anod
iori
te b
ody
loca
ted
near
the
cen
tral
par
t of
the
Jur
upa
Mou
ntai
ns.
Em
plac
emen
t ag
e of
th
e to
nalit
e, b
ased
on
U/P
b an
alys
es o
f zi
rcon
, is
104
+/-
0.4
Ma
(W.R
. Pre
mo,
Wri
tten
Com
., 20
03).
Sr
/Rb
isoc
hron
who
le r
ock
age
is 1
17.6
+/-
6 M
a (R
.W. K
istle
r, W
ritte
n C
om.,
2000
).
Gra
nodi
orite
(K
gd)
gave
a z
irco
n U
/Pb
age
of 1
08 +
/- 6
Ma
(W.R
. Pre
mo,
Wri
tten
Com
., 20
03).
Ton
alite
and
gra
nodi
orite
com
mon
ly h
ave
two
plan
ar f
abri
cs,
a pl
anar
fab
ric
orie
nted
nor
thw
est
that
is
typi
cal
Peni
nsul
ar R
ange
B
atho
lith
and
one
that
is
atyp
ical
str
ikin
g ea
st a
nd n
orth
east
; bo
th
plan
ar f
abri
cs a
re p
rodu
ced
by o
rien
ted
horn
blen
de a
nd b
iotit
e an
d el
lipso
idal
to
panc
ake-
shap
ed m
afic
inc
lusi
ons.
E
ast
and
nort
heas
t or
ient
ed in
clus
ions
are
gen
eral
ly n
otic
eabl
y m
ore
atte
nuat
ed th
an th
e no
rthw
est
orie
nted
inc
lusi
ons.
C
omm
only
a s
ingl
e ou
tcro
p in
clud
es
both
fab
ric
plan
es;
whe
re d
isce
rnib
le t
he n
orth
wes
t st
riki
ng f
abri
c is
ol
der
than
the
east
and
nor
thea
st o
rien
ted
fabr
ic.
The
gra
nitic
roc
ks a
re s
ome
of t
he c
lose
st g
rani
tic r
ocks
to
the
Los
Ang
eles
Met
ropo
litan
are
a th
at c
an b
e us
ed f
or c
onst
ruct
ion
purp
oses
.
As
such
, th
e to
nali
te
and
gran
odio
rite
ha
ve
been
ex
tens
ivel
y qu
arri
ed f
or t
he c
onst
ruct
ion
of b
reak
wat
ers
and
a va
riet
y of
oth
er e
ngin
eeri
ng p
roje
cts.
A
maj
or q
uarr
ying
ope
ratio
n w
as l
ocat
ed a
t th
e no
rth
cent
ral
part
of
the
Juru
pa M
ount
ains
at
Dec
lezv
ille
whe
re a
rai
l lin
e sp
ur w
as c
onst
ruct
ed f
or t
rans
port
atio
n of
ton
alite
. A
noth
er l
arge
qua
rry
is l
ocat
ed i
n th
e hi
lls i
mm
edia
tely
ea
st o
f th
e Ju
rupa
Mou
ntai
ns.
Cur
rent
ly th
e on
ly a
ctiv
e qu
arry
is th
e St
ring
fello
w q
uarr
ies
deve
lope
d in
gra
nodi
orite
and
loc
ated
in
the
sout
h ce
ntra
l par
t of
the
Juru
pa M
ount
ains
.T
he
nort
hern
ha
lf
of
the
quad
rang
le
is
cove
red
by
unco
nsol
idat
ed b
ould
er a
nd c
obbl
e-be
arin
g al
luvi
um o
f th
e di
stal
pa
rt o
f th
e L
ytle
Cre
ek f
an t
hat
eman
ates
fro
m t
he S
an G
abri
el
Mou
ntai
ns n
orth
of
the
quad
rang
le.
An
olde
r al
luvi
al-f
an d
epos
it de
rive
d fr
om t
he e
aste
rn S
an G
abri
el M
ount
ains
onc
e co
vere
d th
e Ju
rupa
Mou
ntai
ns;
cobb
les
of e
aste
rn S
an G
abri
el M
ount
ains
roc
ks,
rem
nant
s of
thi
s no
w v
anis
hed
fan,
occ
ur a
long
rid
ge t
ops
of t
he
Juru
pa M
ount
ains
and
the
hill
to
the
east
of
the
mou
ntai
ns (
Mor
ton
and
Mat
ti, 1
989)
. P
leis
toce
ne a
lluv
ial-
fan
depo
sits
fla
nk t
he s
outh
sid
e of
the
Ju
rupa
Mou
ntai
ns. M
ost o
f th
ese
depo
sits
are
wel
l ind
urat
ed, b
row
n,
sand
y de
posi
ts c
onta
inin
g co
bble
dep
osits
nea
r th
e so
uth
side
of
the
mou
ntai
ns;
clas
ts a
re l
ocal
ly d
eriv
ed f
rom
the
Jur
upa
Mou
ntai
ns.
T
he a
ctiv
e ch
anne
l of
the
Sant
a A
na R
iver
is lo
cate
d in
the
sout
heas
t co
rner
of
the
quad
rang
le. R
EF
ER
EN
CE
S
Bur
nham
, C
.W.,
1959
, C
onta
ct
met
amor
phis
m
of
mag
nesi
um
lim
esto
ne
at
Cre
stm
ore,
C
alif
orni
a:
Geo
logi
cal
Soc
iety
of
A
mer
ica
Bul
letin
, v. 7
0, p
. 879
-970
.E
nglis
h, W
.A.,
1926
, G
eolo
gy a
nd o
il re
sour
ces
of t
he P
uent
e H
ills
regi
on, C
alif
orni
a: U
.S. G
eolo
gica
l Sur
vey
Bul
letin
768
, 110
p.
Jahn
s, R
.H.,
1954
, G
eolo
gy o
f th
e P
enin
sula
r R
ange
s P
rovi
nce,
so
uthe
rn C
alif
orni
a an
d B
aja
Cal
ifor
nia,
in
Jahn
s, R
.H.,
ed.,
Geo
logy
of
sout
hern
Cal
ifor
nia:
Cal
ifor
nia
Div
isio
n of
Min
es
and
Geo
logy
Bul
letin
170
, cha
pter
2, p
. 29-
52.
Mor
ton,
D.M
., 19
78,
Geo
logi
c m
ap o
f th
e Fo
ntan
a 7.
5' q
uadr
angl
e,
San
B
erna
rdin
o an
d R
iver
side
C
ount
ies,
C
alif
orni
a:
U.S
. G
eolo
gica
l Sur
vey
Ope
n-Fi
le R
epor
t 78-
19, s
cale
, 1:2
4,00
0.M
orto
n, D
.M.,
and
Mat
ti, J
.C.,
1989
, A
van
ishe
d la
te P
lioce
ne t
o ea
rly
Plei
stoc
ene
allu
vial
-fan
com
plex
in
the
nort
hern
Per
ris
Blo
ck, s
outh
ern
Cal
ifor
nia,
in
Col
burn
, I.P
., an
d M
inch
, J.,
eds.
, C
ongl
omer
ates
in
basi
n an
alys
is:
A s
ympo
sium
ded
icat
ed t
o A
.O.
Woo
dfor
d:
Pac
ific
S
ecti
on
Soc
iety
of
E
cono
mic
Pa
leon
tolo
gist
s an
d M
iner
alog
ists
, v. 6
2, p
. 73-
80.
Mur
doch
, J.
, an
d W
ebb,
R
.W.,
1966
, M
iner
als
of
Cal
ifor
nia:
C
alif
orni
a D
ivis
ion
of M
ines
and
Geo
logy
Bul
letin
189
.S
trec
keis
en,
A.L
., 19
73,
Plu
toni
c ro
cks—
Cla
ssif
icat
ion
and
nom
encl
atur
e re
com
men
ded
by t
he I
UG
A S
ubco
mm
issi
on o
n Sy
stem
atic
s of
Ign
eous
Roc
ks: G
eotim
es, v
. 18,
p. 2
6-30
.W
oodf
ord,
A.O
., C
ripp
en,
R.A
., an
d G
arne
r, K
.B.,
1941
, Se
ctio
n ac
ross
Com
mer
cial
qua
rry,
Cre
stm
ore,
Cal
ifor
nia:
Am
eric
an
Min
eral
ogis
t, v.
26,
p. 3
51-3
81.
Woo
dfor
d, A
.O.,
Shel
ton,
J.S
., D
oehr
ing,
D.O
., an
d M
orto
n, R
.K.,
1971
, Plio
cene
-Ple
isto
cene
his
tory
of
the
Perr
is B
lock
, sou
ther
n C
alif
orni
a: G
eolo
gica
l So
ciet
y of
Am
eric
a B
ulle
tin,
v. 8
2, p
. 34
21-3
448.
Ver
sion
1.0
By
D. M
. Mor
ton1
Dig
ital
pre
para
tion
by
Kel
ly R
. Bov
ard1
Cla
ssif
icat
ion
of p
luto
nic
rock
type
s (f
rom
IU
GA
, 197
3, a
nd S
trec
keis
en, 1
973)
.A
, alk
ali f
elds
par;
P, p
lagi
ocla
se f
elds
par;
Q, q
uart
z.
Qua
rtz
Syen
iteQ
uart
zM
onzo
nite
Qua
rtz
Mon
zodi
orite
Syen
iteM
onzo
nite
Mon
zodi
orite
Gra
nite
Alkali-feldspar G
ranite
Tonalite
Dio
rite
Syenogranite
Granodiorite
Monzogranite
Quartz
Diorite
9065
3510
5
20
60Q
Q
AP
60
20
5
60
117o 3
0'34
o 7' 3
0"
117
o 30'
34o 0
0'
On
som
e S
CA
MP
ge
olog
ic
map
pl
ots,
in
clud
ing
the
Fon
tana
7.
5'
quad
rang
le,
char
acte
rist
ic g
rain
siz
e in
form
atio
n is
dis
play
ed u
sing
sub
scri
pted
alp
ha c
hara
cter
s (e
.g.,
Qyf
g, Q
ova,
aft
er t
he u
nit
labe
l),
whe
re t
he c
hara
cter
s co
nfor
m t
o th
e fo
llow
ing
defi
nitio
ns:
a -
aren
aceo
us; s
and
or s
and
bear
ing
(ver
y co
arse
san
d th
roug
h ve
ry f
ine
sand
)b
- bo
ulde
rs o
r co
ntai
ning
bou
lder
s (>
25m
m)
g -
grav
el o
r co
ntai
ning
gra
vel (
cobb
le th
roug
h gr
anul
e gr
avel
)s
- si
lt or
silt
yc
- cl
ay o
r cl
ay b
eari
ngm
- m
arl
p -
peat
Whe
re a
uni
t la
bel
has
mor
e th
an o
ne s
ubsc
ript
ed c
hara
cter
, in
all
cas
es,
the
firs
t ch
arac
ter
mod
ifie
s th
e se
cond
(e.
g., Q
yfag
indi
cate
s ar
enac
eous
gra
vel)
.
In th
e D
escr
ipti
on o
f M
ap U
nits
, the
Ma
follo
win
g U
/Pb
ages
has
an
atta
ched
su
bscr
ipt;
Ma i
d fo
r is
otop
e di
lutio
n an
alys
es, a
nd M
a ip
for
ion
prob
e an
alys
es.
15o
1 U.S
. Geo
logi
cal S
urve
y D
epar
tmen
t of
Ear
th S
cien
ces
Uni
vers
ity
of C
alif
orni
a R
iver
side
, CA
925
21
34o 0
0'11
7o 22'
30'
'
117o 2
2' 3
0''
34o 7
' 30"
LOC
AT
ION
MA
P
SUR
RO
UN
DIN
G 7
.5' Q
UA
DR
AN
GL
ES
Coron
a N
orth
Fon
tana
7.5'
Riversi
de
Wes
t
Riversi
de
Eas
t
S
anBern
ardino
Sou
th
Guasti
Cucam
onga
P
eak
Devor
e
S
anBern
ardino
Nor
th
Thi
s re
port
is
prel
imin
ary
and
has
not
been
rev
iew
ed f
or c
onfo
rmity
with
U
.S.
Geo
logi
cal
Sur
vey
edit
oria
l st
anda
rds
or w
ith
the
Nor
th A
mer
ican
S
trat
igra
phic
Cod
e.
Any
use
of
trad
e, f
irm
, or
pro
duct
nam
es i
n th
is
publ
icat
ion
is f
or d
escr
iptiv
e pu
rpos
es o
nly
and
does
not
im
ply
endo
rsem
ent
by th
e U
.S. G
over
nmen
t.
Thi
s m
ap w
as p
rint
ed o
n an
ele
ctro
nic
plot
ter
dire
ctly
fro
m d
igita
l fi
les.
D
imen
sion
al c
alib
ratio
n m
ay v
ary
betw
een
elec
tron
ic p
lotte
rs a
nd b
etw
een
X
and
Y d
irec
tions
on
the
sam
e pl
otte
r, a
nd p
aper
may
cha
nge
size
due
to
atm
osph
eric
con
ditio
ns;
ther
efor
e, s
cale
and
pro
port
ions
may
not
be
true
on
plot
s of
this
map
.D
igita
l fi
les
avai
labl
e on
Wor
ld W
ide
Web
at
http
://ge
opub
s.w
r.us
gs.g
ov/
open
-file
/of0
3-41
8/
Geo
logy
map
ped
by D
.M. M
orto
n; 1
977-
78, 1
990-
99.
Qaf
Qvo
f
Qa
Qyf
l
Qyf
e
Qof
3
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Qof
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Kg
Kgd Kt
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t
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Kt|
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Qya
Qyf
l 1
Qye
Kgd
1
Qya
1
Con
tact
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lid w
here
loca
ted
with
in ±
15 m
eter
s; d
ashe
d w
here
loca
ted
with
in ±
30
met
ers
Kg—
Gra
nitic
dik
es
70
Stri
ke a
nd d
ip o
f ig
neou
s fo
liati
on
I
nclin
ed
V
erti
cal
Stri
ke a
nd d
ip o
f m
etam
orph
ic f
olia
tion
I
nclin
ed
V
erti
cal
Stri
ke a
nd d
ip o
f se
cond
ary
folia
tion
in ig
neou
s ro
cks
I
nclin
ed
V
erti
cal
Bea
ring
and
plu
nge
of ig
neou
s lin
eati
ons
Incl
ined
Bea
ring
and
plu
nge
of m
etam
orph
ic li
neat
ions
I
nclin
ed
70 50
20 55
Hol
com
bC
reek
Shay
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Whi
te M
tn
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bit
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e
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ore
Mil
lC
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Sa
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ive
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h
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er n
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i no
Bas
in
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owhe
adP
eak
But
ler
Pea
k
Arr
owhe
ad
Lak
e
Roc
ks
of
the
Pen
insu
lar
Ran
ges
asse
mbl
age.
Sou
th
of
the
quad
rang
le,
offs
et
Pen
insu
lar
Ran
ges
rock
s oc
cur
east
of
the
San
SA
NG
AB
RI
EL
FA
UL
TC
ogsw
ell
Res
ervo
ir
Sa
nGabr
ielRiver
Sa
nJ
os
eH
ills
San
Ber
nard
ino
Map
of
San
Ber
nard
ino
30' X
60'
qua
dran
gle
show
ing
the
loca
tion
of t
he F
onta
na 7
.5' q
uadr
angl
e.
Col
ored
are
as d
efin
e st
ruct
ural
ass
embl
ages
. A
ppro
xim
ate
loca
tions
of
mos
t fa
ults
ha
ving
lar
ge d
ispl
acem
ents
or
leng
ths
are
show
n.
Infe
rred
bou
ndar
y be
twee
n Pe
nins
ular
Ran
ges
and
San
Gab
riel
Mou
ntai
ns a
ssem
blag
es i
s hi
dden
ben
eath
thi
ck Q
uate
rnar
y de
posi
ts,
and
its lo
catio
n an
d ch
arac
ter
are
hig
hly
spec
ulat
ive.
Tow
n or
geo
grap
hic
feat
ure;
Mou
ntai
n Pe
ak.
SAN
BE
RN
AR
DIN
O
MO
UN
TA
INS
ASS
EM
BL
AG
E
010
515
Km
34°
00'
118°
00'
34°
30'
118°
00'
34°
30'
117°
00' 34
° 00
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7° 0
0'
D ay
Cyn
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peri
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ocks
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pa M
ount
ains
Fon
tana
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ks
of
the
San
G
abri
el
Mou
ntai
ns a
ssem
blag
e.
Incl
udes
ba
sem
ent
(m
ostl
y co
ncea
led
by
Qua
tern
ary
depo
sits
) th
at i
s of
fset
by
the
San
Jaci
nto
Faul
t
Roc
ks
of
the
San
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erna
rdin
o M
ount
ains
ass
embl
age.
In
clud
es
base
men
t (
mos
tly
conc
eale
d by
Q
uate
rnar
y de
posi
ts)
of t
he M
ojav
e D
eser
t, w
hich
is
si
mil
ar
to
San
B
erna
rdin
o M
ount
ains
bas
emen
t
Roc
ks b
ound
ed b
y M
issi
on C
reek
se
gmen
t of
S
an
of
the
And
reas
F
ault
Zon
e,
and
the
Mil
l C
reek
Fa
ult
Oak
Gle
nCr
eek
Sand Cyn
Was
h
CL
EG
HO
RN
FA
UL
T
DE
VIL
CA
NY
ON
FA
UL
TSA
NTA
AN
AC
AN
YO
NF
AU
LT
ZO
NE
GR
AN
ITE
MT
NS
CO
RR
EL
AT
ION
OF
MA
P U
NIT
S
QU
AT
ER
NA
RY
CE
NO
ZO
IC
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ocen
e
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stoc
ene
CR
ET
AC
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ME
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Gen
eric
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tace
ous
rock
s of
the
Pen
insu
lar
Ran
ges
bath
olith
Font
ana
7.5'
Qua
dran
gle
