Tectono-thermal evolution of the Reed Bank Basin, Southern South China Sea

Abstract

The Reed Bank Basin in the southern margin of the South China Sea is considered to be a Cenozoic rifted basin. Tectono-thermal history is widely thought to be important to understand tectonics as well as oil and gas potential of basin. In order to investigate the Cenozoic tectono-thermal history of the Reed Bank Basin, we carried out thermal modeling on one drill well and 22 pseudo-wells using the multi-stage finite stretching model. Two stages of rifting during the time periods of ∼65.5–40.4Ma and ∼40.4–28.4Ma can be recognized from the tectonic subsidence rates, and there are two phases of heating corresponding to the rifting. The reconstructed average basal paleo-heat flow values at the end of the rifting events are ∼60 and ∼66.3mW/m2, respectively. Following the heating periods, this basin has undergone a persistent thermal attenuation phase since ∼28.4Ma and the basal heat flow cooled down to ∼57.8–63.5mW/m2 at present. In combination with the radiogenic heat production of the sedimentary sequences, the surface heat flow of the Reed Bank Basin ranges from ∼60.4 to ∼69.9mW/m2.