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Consider the San Andreas Fault: ever shifting. Generally silent.
Completely underground. It's no surprise then that the fault remains
remarkably elusive.
Scientists
have spent years hard-wiring the tiny Central Valley town of Parkfield,
the park's midpoint, with high-tech gadgetry. Millions of dollars
later, the still can't forecast earthquakes with any consistent
degree of accuracy.
But
if we can’t tell when they're coming, we can certainly see
where they've been. The San Andreas has left visible carvings on
California's surface along its northwestern length, some 650 miles
from the Salton Sea to Point Arena.
The
San Andreas is actually the main branch of a fault system that has
numerous cracks and splinters. It functions like a seam between
two huge tectonic plates.
The
North American plate, housing San Francisco, sits east of the Alaska-bound
Pacific plate, which chugs northwest at the rate of 2 inches per
year.
The
plates constantly gnash along the fault line, building up pressure.
Sometimes, a bit of the seam slips loose. When there's a slip, there's
an earthquake. A big slip is like a giant zipper ripping through
the earth.
That's
what happened April 18, 1906, when a Richter magnitude 8.3 quake
ruptured Northern California's surface for 300 miles and ignited
the firestorm that consumed San Francisco.
Seismologists
divide the fault into three sections. The northern segment is relatively
calm, the '06 quake having uncorked some stress. The central segment,
from San Juan Bautista to Cholame, creeps along, belching out midsize,
tension-relieving temblors at various intervals.
But
the southern section is overdue, seismologists say, and ripe for
a whopper.
Though
shadowed by the Big One, most Californians don't fret much about
the San Andreas Fault. San Francisco has even dammed it to hold
the city's water supply (at San Andreas Lake, a sag pond that formed
in the valley of the fault).
Nonetheless,
April isn't California Earthquake Preparedness Month for naught.
South
to North
1.
Salton Sea State Recreation Area: The fault begins beneath
California's largest man-made lake, along the Pacific Flyway. (760)
393-3052
2.
Palm Springs: For companies that tour giant cracks in the
desert: (760) 325-1577.
3 Universal Studios, Los Angeles: Can't wait for the real
thing? Try the park's simulated 8.3 temblor. (800) 959-9688.
4.
Fort Tejon State Historic Park: in 1857, the state's strongest
recorded quake collapsed this former military post. (661) 248-6692.
5.
Carrizo Plain: The remote section of the fault features zigzagging
streams, and visible scars in the high desert.
6.
Parkfield: Major quakes here used to average once every 22
years. Since the U.S. Geological Survey set up camp, the quakes
have gone into hiding.
7.
Pinnacles National Monument: Volcanic remnants straddling
the fault feature two distinct geologies, making for great rock
climbing. (831) 389-4485.
8.
Mission San Juan Bautista: Since 1797, the mission has sat
astride the fault and withstood numerous quakes. (831) 623-4528.
9.
Los Trancos Preserve: The fault splits this preserve in the
Santa Cruz Mountains. From a trail, you can spot Crystal Springs
Reservoir, built before engineers knew the depression was made by
the fault. (650) 691-1200
10.
Mussel Rock, Daly City: This coastal outcropping marks the
fault's departure out to sea. Check out the Mussel Rock segment
of the Ridge Trail.
11.
San Francisco: Quake survivors gather at Lotta's Fountain
5:13 a.m. every April 18 to remember the 1906 quake. They meet at
the St. Francis Hotel. (415) 774-0381.
12.
Bolinas Lagoon: Created by the fault; each Fourth of July
townsfolk hold a tug-of-war across the breach. (415) 868-1444.
13.
Point Reyes National Seashore: Located on the Pacific Plate
that lurches northwest during a quake, carrying this seashore with
it. (415) 663-1092
–
Jay Cooke is a San Francisco-based travel, food, and culture writer.
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