san andreas
TRANSCRIPT
Transforming California
Landforms of the San Andreas FaultImages & text by Thomas McGuire, Cave Creek Digital, Cave Creek, [email protected]
“If we intend to live on this planet… we truly need to understand how it works.”
Exploring ways to find fault…
3The author at Parkfield CA, site of USGS seismic experiment. “Be here when it happens!”
4
Fault Issues1. Fault Scarps & Alignments2. Sag Ponds3. Offset Drainages4. Distortion of Human-Made Structures5. Infrastructure Vulnerability
5
BasicCaliforniaGeograph
yImperialValley
Los Angeles
Mojave Desert
SanJoaquinValley
San Francisco
SanAndreas
Fault
Death Valley
6San Andreas Lakes viewed from the south near San Jose
7
The San Andreas fault is part of the boundary between the North American and Pacific tectonic plates. It is classified as a right lateral transform fault.
(To a person facing the fault,
the far side shifts to the right.)
Our Dynamic Earth, Robert Tilling, USGS, 1996
8The Sea of Cortez.. (Known to Gringos as The Gulf of California.)
9The US-Mexican Border (fence line) is as impervious to plate processes as it is to immigration.
10The All-American Canal brings Colorado River water to the Imperial Valley of California.
11Wind Farm north of Palm Springs near San Gorgonio Pass.
12The main trace of the fault runs NE of Los Angeles, but numerous splay faults affect the LA Basin.. (So does smog.)
13California Aqueduct at Palmdale, north of Los Angeles.
14Gates along the California Aqueduct at Palmdale
15San Andreas Fault road cut, CA 14 at Palmdale,
16Detail of CA 14 road cut at Palmdale
17Intersection of the San Andreas & Garlock Faults east of Tejon Pass.
18John Marquis, USC
The
San
Andreas
and
Garlock
Faults
19Remains of Manzanar Japanese American internment Camp (WWII) and the steep eastern front of the Sierra Nevada Mountains
20
Columnar jointing in basalt at Devil’s Postpile near Mammoth Lakes, CA
21
Top of jointed basalt columns, Devil’s Postpile, CA
22Dante’s View, Death Valley, CA. Badwater, at -282 Ft, the lowest place in the Western Hemisphere, is at the bottom right.
23
24San Andreas Fault, Carrizo Plain just north of CA 166.
25
Fence (see last slide) crosses San Andreas Fault near CA 166.
26San Andreas Fault ridge, Elkhorn Scarp along the base of the Tremblor Range, Carrizo Plain, CA
27Fault trace, Carrizo Plain, CA
28San Andreas Fault, Carrizo Plain, CA
29Stream offset along the San Andreas Fault, Carrizo Plain, CA
30Soda Lake, Carrizo Plain,. A closed drainage (sag pond) feature.
31
Wallace Creek, USGS aerial view, about 1990 USGS Photo
32
Wallace Creek fault investigation area on the Carrizo Plain. Numbers show signed posted nature trail features. Next image at #1..
33Tom at Wallace Creek fault offset .
34Stream offset along the San Andreas Fault near Wallace Creek, CA
35Stream offset north of the Carrizo Plain, on Bitterwater Road.
36Sag pond, San Andreas Fault along CA 25.
37San Andreas cable crossing & sag pond, CA Route 25.
38
Sheared tree limbs along CA, Route 25
; )
39San Andreas Fault trace, CA Route 25.
40California Route 25 along the San Andreas Fault.
41Pressure Ridge, California Route 25.
42San Andreas fault scarp & sag pond just east of California Route 25.
43Slump structure near the San Andreas Fault, California Route 25.
44Parkfield, CA. USGS seismic experiment center.
45Laser triangulation and GPS site, Parkfield, CA
46Bridge across San Andreas Fault at Parkfield
47
San Andreas Fault right lateral offset at Parkfield Bridge
48San Andreas Fault Movement, DeRose Winery, Hollister, CA Note the new building at the top left.
49
28 years of offset at the Cienga Winery, USGS Photo TMcG
50New construction & fault trace, June 2003, DeRose Cienga Winery. The offset ditch runs barely out of sight on the right.
51
San Andreas fault creep damage
De Rose Cienga Winery, south of Hollister CA
52Town of Hollister, California viewed from the Calaveras fault scarp. The San Andreas fault runs sub-parallel l,.5 miles west.
53Wall on 6th Street distorted by Calaveras Fault creep (June 2003)
54
Rotational Translation on 6th Street
55
Offset curb,
6th Street
Hollister
56
Offset curb
on,7th Street
57Roof damage, Hollister High School
58
Discrepant Event, Hollister ; )
595th Street, Hollister.
60
5th Street
Detail #1
61
5th Street
Detail #2
625th Street Detail #3
634th Street front steps..
64Displaced sidewalk, 359 Locust Avenue, Hollister
65Retaining wall, 359 Locust Avenue, Hollister.
66
Locust Avenue Garage
& power pole.
Garage built in 1929
67
Locust
Avenue
Curb &
utilities
68USGS, Menlo Park (Bay Area) Research Center
69
The San Andreas Fault passes a few kilometers west (left) of the Golden Gate Bridge.
San Francisco Tourism Photo
70Bye bye to the fault! (Point Reyes)
71Seismology & economics converge
72
TheEnd. USGS map
California
Transformed