geologic considerations in conservation planning part 2 southern california geology (12/02)
TRANSCRIPT
Geologic Considerations in Conservation
PlanningPart 2
Southern California Geology
(12/02)
http://www.geol.ucsb.edu/Outreach/Download/Freeware-FR.html
Geology of Southern California
San Andreas Garlock
San Jacinto
Elsinore
Imperial
Eastern
CA Shear
Zone
Landers6/28/92 Mw 7.3
The“Big Bend”
San Andreas Garlock
San Jacinto
Elsinore
Imperial
Eastern
CA Shear
Zone
Ventura
San Cayetano
San FernandoHollywood/Raymond
Cucamonga
Northridge1/17/94 Mw 6.7
Transverse Ranges
Mojave
Colorado Desert
Peninsular Ranges
Los Angeles Basin
Pint
o
Eagle
Little
San
Berna
rdin
o
San
Bern
ardi
no
San
Gab
riel
Santa
MonicaChan
nel
Isles
Santa
Ynez
Piru
Pine
Topatopa I-5/G
rape
vine
Cajo
n Pa
ss
San
Gorgo
nio
Pass
Rifting, Rotation, and Volcanism in the Western Transverse Ranges
Rifting, Rotation, and Volcanism in the Western Transverse Ranges
Rifting, Rotation, and Volcanism in the Western Transverse Ranges
Los Angeles Basin5 million years ago
Sharp, 1994
Santa Monica/Hollywood/Raymond
Sierra Madre/Cucamonga F.Z.
Whittier
Chino
Palos Verdes Hills
Newport-Inglewood
El Moreno
San Jose
Anticline
LAW
POSM
SG
SA
LB
Syncline
San FelipeHills
Agua Tibia
SanJacinto
Santa Rosa
San Timoteo
BorregoValley
AnzaUpland
SantaAna
Laguna
SantaMargarita
Cuyamaca SD
OE
F
El
R
SJ
V
M
P
Br
29
Bk
N
A
Tehachapi/
So. Sierra
Neva
da
San GabrielsSan Bernardino Little S.B./Pinto Whipple
Turtle
El Paso
ArgusSlate Avawatz
Providence
OldWoman
Old DadG
G
G
GBullion
Cady
Bristol
San Andreas
Garloc
k
Pinto Mtn
Eastern
CA Shear
Zone
Cima Volcanic Dome(330-480 years old)
Cima Volcanics(330-480 years old)
Alluvial Fan, Death Valley
Sand Dunes
• Occur in both deserts• Various types of sand
dunes are present• Found in valleys• Some have unique
acoustic properties
Fish Cr.
SantaRosa
Superstition
Vallecito
Coyote
McCoyWash
CargoMuchacho
Eagle
Cockscomb PalenIndioHills
EC
I
N
BOrocopaChuckawallaChocolate
East Mesa
Palo Verde
EC
I
N
B
San Gorgonio Pass/No. & So. Branches San Andreas
Sand Hills ?
Elsinore/Laguna Salada
San Jacinto/Coyote Cr./SuperstitionHills/Imperial
Elmore Ranch/ Brawley
Badlands
• Relatively rare for California
• Carrizo and Indio Hills
• Sculpted by infrequent flash floods
• Sparsely Vegetated
Salton Sea History• Periodic Holocene inundation
(beach ridges)• Lake Cahuilla 700 A.D. to
approx. 300 years ago.• 1824-1904: Inundation at least
8 times;• 1905: Accidental diversion of
Colorado River through Irrigation Canals (1907 closure)
• Agricultural runoff maintains present lake levels
Algodones Dunes
• Built by Colorado River sediments and erosion of bordering ranges
• 320 square miles• Moving southeast due to prevailing
winds (6-12 in/yr)