Abstract: Tectonic Evolution of the East China Sea Basin--Implication for the Development of the Western Pacific Marginal Seas

G. Ming Wang, Michael P. Coward, Wenguang Yuan, Jinhai Zhao, Shenshu Liu, Wenqiang Wang

A number of marginal sea basins occur in the western Pacific, including the Sea of Japan, East China Sea, and South China Sea. These basins developed in response to the combined forces of (1) the subducting Pacific and Philippines Sea plates and (2) the movement of blocks escaping from the Himalayan collision belt. Inversion of these basins was due to deformation in pushup zones in regional strike-slip fault zones, changes in subduction/convergence rate, and collision of thick, buoyant, continental crust in the subduction zone. The variation of evolution of the marginal seas is further complicated by the role of transform faults, particularly those reactivating basement structures.

The East China Sea basin is a large Cenozoic basin developed on the passive margin of the Eurasia plate. Rifting in the Late Cretaceous/Paleocene was followed by deposition of a thick postrift sequence in the main part of the basin. Prominent inversions of the basin occurred in the Oligocene and Miocene when a thrust belt developed along its eastern margin and anticlines developed in a pushup zone in the main part of the basin. Progressive development of back-arc spreading has further opened the Okinawa Trough in the east since late Miocene. Variations in structure and basin history occur along the length of the basin emphasizing the role of transform faults.

This contribution will discuss the evolutionary history and regional variations in basin development in the East China Sea and compare these with the evolution of the Sea of Japan to the north and Taiwan to the south. These discussions aim to establish a regional model for the development of the eastern Pacific marginal seas.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994