[Geysers] Parkfield CA SAFOD earthquake research project

[Freund, Udo]

Welcome to Quake Central
Parkfield's proximity to the San Andreas Fault and reputation for
temblors have attracted scientists to the community who are studying how
faults work and how earthquakes happen
David Sneed
The Tribune
PASO ROBLES - Parkfield is known for its many earthquakes.
That reputation has caused scientists to turn the small ranching
community just across the Monterey-San Luis Obispo County line into the
world's foremost center for seismic research.
On June 11, a 182-foot-tall drill rig cut into the earth on a ranch
northwest of Parkfield. Over this summer and next, the rig will bore
more than 10,000 feet into the Earth and place an array of sensors
across the San Andreas Fault.
The goal of the project, called the San Andreas Fault Observatory at
Depth or SAFOD, is to allow scientists to study how faults work and how
earthquakes happen. They hope eventually to use the data they collect to
do what no one has done -- accurately predict earthquakes.
"In essence, it's the Hubble telescope underground," said Rep. Sam Farr,
D-Carmel, whose district includes the Parkfield area.
The project will be built over the next five years and will cost nearly
$300 million. It is a cooperative effort of the National Science
Foundation, the U.S. Geological Survey and numerous universities.
The Central Coast regularly experiences earthquakes. The most recent,
the magnitude 6.5 San Simeon Earthquake, killed two women in December
when the Acorn building collapsed in Paso Robles.
The San Andreas Fault is the area's most active and marks the boundary
between the Pacific and North American tectonic plates. It cuts across
eastern San Luis Obispo and Monterey counties "like a hot knife through
butter," said Bill Ellsworth, a leading expert on the fault with the
USGS.
Since drilling began in June on the Bear Valley Ranch, 25 miles
northeast of Paso Robles, the rig has already penetrated more than 7,000
feet. Work will stop for the winter before the bore hole actually
crosses the San Andreas Fault.
Work will resume next summer with drilling concluding in 2007.
Scientists will spend 15 years after that monitoring the fault with more
than 100 instruments that will measure temperature, pressure and the
Earth's tiniest movements.
"It will be the largest earthquake observatory in the world," said Andy
Snyder, a scientist with the USGS.
All data produced by the project will be transferred by satellite and
made available via the Internet almost immediately for study by
scientists and educators.
Geologists consider Parkfield the ideal place to study earthquakes. That
stretch of the fault has produced six moderate to strong earthquakes
since 1857, an average of one every 20 years.
The last one -- a magnitude 6 temblor -- occurred in 1966. The next one
was due by 1987 but has not yet occurred.
Scientists fear that, because so much pressure has built up along the
fault, the next quake will be of a magnitude 7 or greater. A temblor
that strong could cause serious damage in San Luis Obispo and Paso
Robles where many of the buildings are made of unreinforced masonry,
Ellsworth said.
With the SAFOD project in place, geologists will be able to record in
unprecedented detail the next significant quake along the San Andreas as
well as numerous smaller ones.
Kevin Kester, owner of the 10,000-acre ranch where the SAFOD drill sits
among rolling oak woodlands, said his family has experienced many
earthquakes since they bought the property in the 1860s. After the 1966
Parkfield earthquake, scientists placed many seismographs and other
earthquake-detecting instruments on the ranch.
"Since 1966 to the present, our ranch has been the focus of a great deal
of scientific research," Kester said. "It's our way of furthering
research and contributing to the ability to predict earthquakes
someday."

Udo Freund
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