Juxtaposed sequence stratigraphy, temporal-spatial variations of sedimentation and development of modern-forming forearc Lichi Melange in North Luzon Trough forearc basin onshore and offshore eastern Taiwan: An overview

摘要

The South China Sea oceanic lithosphere has been subducting eastward beneath the Huatung Basin/Philippine Sea Plate since the Early Miocene (similar to 18 Ma). The subduction is followed by the oblique collision between the Luzon arc and the subducting Eurasian plate from 6.5 Ma. The North Luzon Trough forearc strata and the Luzon arc are then obducted northwestward as the Coastal Range, eastern Taiwan, in the last 1 Ma. The collision propagates southward and is presently active in the region offshore SE Taiwan. Integrating seismic surveys offshore and a detailed forearc stratigraphy study onshore the Coastal Range, this paper overviews the characteristics of forearc deformation, dynamic sequence stratigraphy, temporal-spatial variations of forearc sedimentation and stratigraphic correlation onshore and offshore forearc sequences in response to the oblique convergent tectonics north of 20 degrees N. Combining onshore and offshore forearc geology together allows us to reconstruct a structural evolution of the North Luzon Trough forearc basin from subduction through collision to obduction, and to discuss the mechanism and processes responsible for developments of the modern-forming forearc Lichi Melange during the active Taiwan orogeny.