A magnitude 7.6 earthquake occurred on September 21, 1999, near Chi-Chi in Nantou county, Taiwan, about 90 miles south of Taipei, resulting in extensive damage, injuries and loss of life. Extensive damage occurred to bridges and dams and, due to the mountainous nature of the terrain, there were hundreds of s landslides, including several very large catastrophic landslides. A very important feature of this earthquake was the reverse fault rupture with vertical displacements ranging from 2 meters along the southern section to as much as 8 meters along the northern terminus. The fault rupture extends through heavily developed areas and is responsible for much of the damage to major transportation and river control structures. Since much of northern and southern California has extensive infrastructure development along active fault traces, observing and documenting the direct impact of large fault displacement in the Taiwan earthquake is of obvious practical and research interest to the US earthquake engineering community.
This action provides partial support for a coordinated industry-academia reconnaissance team to document the geotechnical and engineering geology/seismology features of this earthquake in as much detail as possible. Of particular interest is the impact of large seismic fault offset on urban infrastructure.
As with all post-earthquake reconnaissance investigations, it is expected that vital records and data will become available as a result of this earthquake in Taiwan. From a scientific viewpoint, these large earthquakes act as full scale experiments that cannot be duplicated via controlled experiments in the laboratory or in the field. It is through quick response reconnaissance efforts that the mostly-ephemeral data from these events can be recovered and used to further advances in earthquake hazard mitigation. The results from this investigation are expected to yield information and data that will help the profession to understand the impact of large seismic fault offset on urban infrastructure.
This is a multi-institutional award involving the University of California at Berkeley, the University of Washington, and the University of Southern California.