NUMERICAL SIMULATION OF THRUST STRUCTURAL INVERSION FOR TAIWAN FORE-ARC BASIN

The Taiwan orogenic belt, located in the juncture of the Eurasian plate and the Philippine Sea plate, is one of the youngest active orogenic belts in the world within a unique geological environment. The Coastal Mountains, which is located in the east of the Island, are composed of a residual fore-arc basin and a volcanic island, and the former of which is evolved from the fore-arc basin of the north Luzon Trough after two-stages of strong extrusion of shearing structure. This paper adopts FLAC6.0 to simulate the thrust structural inversion of the Taiwan fore-arc basin. It is found out through analysis of simulation results that the reversal of thrust structure in the Taiwan fore-arc basin is developed from east to west gradually, and evolves from local tectonic inversion in the beginning to overall thrust structure westward finally. In addition, stratum thickness and slope angle of basement plays certain control roles in the formation and evolution of folding.