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SACRAMENTO – Although
the view of the Himalayas is stunning,
Pakistan might not be Dr. Anthony
Shakal’s first choice for a quick
getaway. But as a location in which to
further the scientific community’s
knowledge of earthquakes and foster
international cooperation, it was
practically paradise.
Shakal, who has led
the California Geological Survey’s
Strong Motion Instrumentation Program (SMIP)
for nearly a quarter of a century,
recently spent a week in Pakistan to
help the country begin its own strong
motion program.
“It was quite an
experience,” Shakal said. “Pakistan has
a unique seismic environment. It’s part
of the Indian tectonic plate that is
pushing into the Asian plate and
continually increasing the height of the
Himalayas. It’s a very interesting place
to be, from an Earth science point of
view.
The Indian plate
moves about five centimeters a year --
about double the movement seen along the
San Andreas Fault. The faulting regime
in Pakistan is similar to that of
Southern California, with a number of
significant blind-thrust faults, like
the one that caused the Northridge
earthquake.
In October of 2005,
Pakistan experienced a magnitude 7.6
earthquake – slightly smaller than the
Great San Francisco Earthquake of 1906 –
that caused 80,000 deaths and billions
of dollars in damage.
Realizing that
improved building codes and earthquake
preparedness techniques could help
reduce the destruction caused by future
earthquakes, Pakistan dispatched
professor Ali Syed of the Earthquake
Engineering Center at the University of
Engineering and Technology in Peshawar
to the United States. Syed met with
officials from the California Institute
of Technology, the U.S. Geological
Survey, UC Berkeley and CGS, a branch of
the California Department of
Conservation.
The Earthquake
Engineering Research Institute – an
Oakland-based association dedicated to
reducing the risk of earthquakes to the
public – suggested holding an exchange
visit. Shakal was nominated to
participate, and the National Academy of
Science arranged the trip. The U.S.
Agency for International Development
covered his expenses.
"It was an honor to
have California’s strong motion program
selected as a model by a foreign nation
working to establish its own program,”
said State Geologist Dr. John Parrish,
head of CGS. “Pakistan turned to
California for advice and assistance in
recognition that the state has taken a
lead role in addressing earthquake
issues. We were pleased to cooperate."
In years past, Shakal
visited India and CGS engineer Dr. Moh
Huang traveled to Japan to compare notes
on seismic monitoring. An invitation to
visit China and help with their program
expansion is under consideration.
“When the magnitude
7.6 earthquake struck, Pakistan didn’t
have active building codes in place,”
Shakal said. “In Islamabad, the capital,
a 12-story building collapsed in the
earthquake. The Pakistanis were
interested in setting up a monitoring
system that would describe how their
buildings respond to earthquakes and how
the ground shaking there is affected by
distance from the epicenter to help
their engineers raise the level of
seismic safety in their designs. We told
professor Syed about policies and
procedures used here in California when
he visited. The Pakistani government
thought it made a lot of sense to move
in that direction.”
SMIP was established
in 1971, after the devastating San
Fernando earthquake, to obtain vital
data for the engineering and scientific
communities through a statewide network
of instruments. When activated by
earthquake shaking, these
“accelerographs” produce a record from
which the critical characteristics of
ground motion – acceleration, velocity
and displacement – can be calculated.
The information is
processed and disseminated to
seismologists, engineers, building
officials, local governments and
emergency response personnel throughout
the state. The data is used primarily to
recommend changes to building codes, and
assist local governments in their
general plan process. SMIP also partners
with the USGS, California Institute of
Technology and UC Berkeley in the
California Integrated Seismic Network.
Real-time data collected by the network
is used to produce a “ShakeMap” within
minutes of a strong earthquake to help
guide emergency response efforts.
The Applied
Technology Council last year honored
SMIP as one of the top seismic programs
of the 20th century.
“Pakistan has decided
to name their program PkSMIP, which we
take to be a real compliment,” Parrish
said.
SMIP has installed
more than 1,000 instrument stations
around the state in a variety of
structures, including major bridges,
high-rise buildings, dams, hospitals and
industrial facilities. Among the
instrumented sites are the city halls of
Los Angeles, San Francisco and Oakland,
and the state capitol. Accelerographs
also are placed in open land to measure
the motion of the ground and the effects
of earthquake shaking on different types
of soils. An advisory committee of
engineers and scientists representing
industry, government and universities
help select SMIP’s station locations.
SMIP technicians are currently working
on bridges in the Bay area and Long
Beach.
While in Pakistan,
Shakal helped his colleagues plan the
instrumentation of two bridges and two
buildings in the Islamabad and Peshawar
areas.
“We studied the
blueprints and laid out sensor
configuration plans,” Shakal said. “They
will go through similar procedures on
other structures. In the first phase,
they plan to instrument 12 structures.
They’re off to a good start.”
In exchange for their
expertise, CGS will be fed information
from the Pakistani program.
“We’re likely to get
data from large earthquakes sooner from
Pakistan than we are from California,”
Shakal said. “We have records from many
earthquakes magnitude 6 and smaller, but
only a few from magnitude 7 and larger
events. These records are really needed
to guide the design of structures to
withstand the big events – but we have
few records of what the forces are like.
There’s a little uncertainty about the
frequency of large earthquakes in
Pakistan, but they’re definitely in
harm’s way and have more frequent large
earthquakes than we do.”
Overall, Shakal was
impressed with Pakistan’s commitment to
improving seismic safety.
“A striking thing is
that despite the difficulties facing the
country, there is a core of dedicated
people, many with degrees from U.S.
universities, trying to make real
improvements,” he said. “Although
Pakistan is not a rich country, if the
regional tensions are settled, the
people there can make good progress in
their country.”
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