The exchanges have begun a scientific relationship that will continue, perhaps for years, as more researchers and students travel between China and Kentucky.
In early May, three researchers from China's Lanzhou Institute of Seismology visited Kentucky to share their research experience and to learn more about earthquake research in Kentucky. Institute Director Lanmin Wang, Engineering Seismology Professor Yucheng Shi and Geology Professor Daoyang Yuan also visited sites in the Kentucky Seismic and Strong-Motion Network in the western part of the state.
Following that visit, four KGS and UK scientists paid a visit to Gansu Province, where the Lanzhou Institute is located, during the last week of June and first week of July. KGS Director Jim Cobb, Assistant State Geologist John Kiefer, Zhenming Wang of the KGS Geologic Hazards Section and Ed Woolery of the Geological Sciences Department were guests of the Institute and China's Earthquake Administration.
The huge province is home to sections of the Great Wall as well as the historic Silk Road and the location of some major earthquakes in the past century. Both the similarities and the differences between Kentucky and Gansu Province should help Chinese and Kentucky researchers in their cooperative work. Both regions are monitored for by seismic instruments and both have a history of large and damaging earthquakes.
Seismic researchers from China will travel to Kentucky in September, and UK and Chinese graduate students will begin traveling between the two countries to study and conduct research in the next several years as a result of the partnership.
A workshop is being planned for the summer of 2006 either at UK or in China to share information on identifying active geologic faults.
In 1920, the Gansu province experienced an 8.5-magnitude earthquake which took a reported 230,000 lives. The entire Central United States, including Kentucky, was shaken in 1812 by an earthquake, which would have registered an estimated 8.0 on the Richter Scale.
"A major difference between the geologic faults associated with earthquakes in the region we visited in China and the faults in western Kentucky is that the Chinese faults are exposed at the ground surface, whereas ours are concealed, sometimes deep underground," Cobb said. "As we continue to exchange information and visits, we hope to be able to learn more about how the Chinese faults produce earthquakes."
Cobb added that this work will help to better interpret faults in Kentucky and how they, too, produce earthquakes.
Another similarity between the two regions involves the surface material covering at least part of the earthquake-threatened areas in both regions. Parts of Gansu Province, including developed areas of the city of Lanzhou are covered with a thick layer of loess, a wind-blown silt deposit whose characteristics and behavior in earthquakes are similar to the liquefaction-prone deposits found in western Kentucky and the rest of the New Madrid Seismic Zone. However, whereas Kentucky's deposits are only a few meters in thickness, over 400 meters of loess blankets part of Gansu Province.
"This material in Gansu Province is a difficult material to build on and unstable for construction," Kiefer said. "It is analogous to the surface material found along the Ohio, Mississippi and other River valleys of the New Madrid Zone. Research in this area, along with previous earthquake experience, has shown this material can amplify earthquake motions coming from the bedrock below, posing a greater threat to the built environment on the ground surface."
Kiefer adds that the kind of "people to people" contacts being made between the Chinese and American scientists can make a difference for both regions as they seek solutions to their common earthquake threat to populations and the built environment.