CENOZOIC TECTONIC EVOLUTION OF WUQIUYU DEPRESSION,TAIXI BASIN

In this paper, regional geology and seismic data are studied for Cenozoic structures and tectonic evolution of the Wuqiuyu Depression of the Taixi Basin. The tectonic evolution of the Taixi Basin is affected by the interaction of the Eurasian Plate, Indian Plate, the Pacific Plate and the Philippine Sea Plate. In Late Mesozoic, the regional stress field of the Taixi Basin changed from compression to extention, and the crust became thinning, that resulted in the early Cenozoic extensional rift of the Wuqiuyu Depression, a half-graben marginal rift basin bounded by fault in the west and overlapping in the east. The tectonic evolution of the Wuqiuyu Depression may be divided into four stages, i.e. the pre-riftig stage of Late Mesozoic, the rifting stage from Paleocene to Oligocene, the depression stage of Miocene and the sedimentation stage from Pliocene to Quaternary.