Texas Tech Geosciences Professor Measuring Aftershocks of China Earthquake
May 16, 2008
Professor and students study seismic activity of critical area near China's largest
Just 40 minutes before the May 12 earthquake measuring 7.9 on the Richter scale
struck the Sichuan province in Central China, a Texas Tech University professor of
geosciences had arrived in Beijing, only 960 miles away.
Hua-wei Zhou, professor of petroleum geophysics and seismology, was about to start
work for the National Natural Science Foundation of China to monitor smaller earthquakes
by the Three Gorges reservoir, 250 miles east of the Sichuan earthquake epicenter.
Now, Zhou is leading a team of six graduate students to deploy 60 seismometers to
the Three Gorges area. The team hopes to record aftershocks that will help reveal
the structure of the Earth’s crust in this area. Though there is no reported damage
to the hydroelectric dam in Three Gorges by the killer earthquake in Sichuan, Zhou
said it is imperative to study the safety of the dam during an earthquake.
Failure of the dam could result in one of the worst disasters in history, as more
than 75 million people live downstream of the dam, and the floodplain surrounding
the Yangtze River is used for growing much of the country’s food.
Zhou said the destructive earthquake occurred on the Longmenshan fault, which has
many historic earthquakes greater than magnitude 7, which is capable of widespread,
heavy damage. The last one occurred in 1933.
"While the Sichuan earthquake is a major human tragedy, the situation could have been
even worse considering that the city of Chengdu, with a population of 4 million, is
just 60 miles away from the epicenter," Zhou said. "First, Chengdu is on the footwall
side of the northeast-trending Longmenshan fault, and the footwall side usually has
much less damage than the hanging wall side. Second, the northeast-trending fault
and northeast rupture direction put most rupture energy away from the city of Chengdu
and its population.
"However, the region near and to the northeast side of the fault will suffer a lot,
though that region has much smaller population density than Chengdu."
Another large earthquake occurred in 1973 on the nearby Xianshuihe fault to the southwest,
"In 1986 I spent two months in the field studying that fault with several colleagues,"
he said. "The main driving force of all these earthquakes is the collision of the
Indian and Eurasian plates that pushes the mountains against the Sichuan basin."
CONTACT: Hua-wei Zhou, Pevehouse Chair and professor of petroleum geophysics and seismology
in the Department of Geosciences, Texas Tech University, firstname.lastname@example.org