The configuration of the Chelungpu fault that caused the 1999 magnitude 7.6 Chi Chi earthquake has been the target of many studies. New work by Gong-Ruei Ho, Ping-Yu Chang, Jian-Cheng Lee, Jonathan Lewis , Po-Tsun, and Chen Han-Lun Hsu suggests that the Sanyi fault that branches westward from the Chelungpu poses risks to developed areas.

The work, published recently in Engineering Geology, synthesizes outcrop observations, shallow geophysical survey results, geochronology constraints, and borehole data from fault zone-drilling to map the surface trace of the fault zone through populated areas east of Fengyuan city. Authors Ho and Lee of the Institute of Earth Sciences at Academia Sinica continue to collaborate with Lewis on active mountain building in the eastern Central Range on the other side of the island. Although the COVID-19 pandemic has put planned field work on hold, IUP undergraduates Susie Adams and Lauren Donati are actively working on data from prior field efforts.They look forward to post-pandemic work addressing myriad geological mysteries in Taiwan.


Gong-Ruei Ho, Ping-Yu Chang, Jian-Cheng Lee, Jonathan C. Lewis, Po-Tsun Chen, Han-Lun Hsu, Surface traces and related deformation structures of the southern Sanyi Fault, Taiwan, as deduced from field mapping, electrical-resistivity tomography, and shallow drilling, Engineering Geology, Volume 273, 2020, 105690, ISSN 0013-7952

Department of Geoscience