Towards geodynamic models of the Taiwan orogenic belt

Abstract:

The Taiwan orogenic belt, which consists of the backbone mountainous Central Range, the Hsueshan Range, and the active fold-and-thrust western foothills, is a spotlight for orogenic studies. Based on thermochronologic and geodetic data, the Central Range has very rapid exhumation and uplift rates during the latest orogenic event. Several studies have proposed different models for the geometry of the Taiwan orogenic belt and varied explanations for the rapid rates of the Central Range. However, the geometry and the processes of the Taiwan orogenic belt are still under debate. Here we present results of recent seismic activities that the current Taiwan orogenic belt shows the geometry of a doubly-vergent wedge. Numerical models with the doubly-vergent geometry also fit present-day surface velocities derived from geodetic observations. Thermochronology data can provide insights into long-term deformation history of the Central Range and Hsueshan Range. We are working towards integrating long-term data such as thermochronologic dating and field mapping and short-term geophysical and geodetic data to reconstruct different stages of mountain building history of the Taiwan orogenic belt.