GEOPHYSICAL AND STRUCTURAL HAZARD ASSESSMENT OF THE HUKOU ANTICLINE, TAIWAN

Collision between the Philippine Sea Plate and the Eurasian Plate is responsible for the creation of the Taiwan Orogeny. Present day Taiwan is a product of both subduction and obduction of the Philippine plate at both the Ryukyu Trench and Manila Trench respectively. Obduction of the Philippine Plate over the Eurasian Plate at the Manila Trench is responsible for much of Taiwan's geographical features from the Central Ranges westward. Volcanism in northern Taiwan is likely due to the volcanic arc formed at the Ryukyu Trench. As a result of movement on the Philippine Plate, the Luzon Arc was transported towards Taiwan where it collided to form the present day coastal ranges.

This project focuses on the tectonically active northwest region of Taiwan, particularly the Hukou anticline. Hukou anticline is one of a series of fault-cored antclines in the active fold-and-thrust belt. Interpretation of field data coupled with seismic reflection data, well logs, and geodetic data (GPS and leveling) is used to produce a tectonic model of the growth of the anticline and its relationship to ongoing shortening in the region. To assess earthquake hazard associated with growth of Hukou anticline, we are using subsurface fold geometry and models of fault-related folding to locate the blind thrust and determine the fault slip rate.