Structural Deformation and Exploration Hydrocarbon Plays in Northern Sichuan Basin, China

He, Dengfa ¹; Fan, Chun ¹; Guan, Shuwei ²; Wen, Zhu ¹; Li, Benliang ²; Lu, Renqi ^1
1 Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism, Ministry of Education; China University of Geosciences, Beijing, China.
² PetroChina Exploration and Development Institute, Beijing, China.

The strata of Late Paleozoic to Middle Triassic are the predominant plays for petroleum exploration in northern Sichuan Basin. Up to now, the evolutionary stages, structural attributes, composition, superimposed and composite development of the northern continental margin of the Sichuan Continental Block, the relationship between the continental margin and the interior of the craton, as well as the structural deformation processes during the late stage and the final preservation have not been systematically or thoroughly addressed as a whole. This paper aims to choose the northern Sichuan area, the promising area for marine hydrocarbon exploration and the hot area for continental geodynamic research, as the ideal natural lab to restore the structural framework and the evolutionary processes of the uplifting and subsiding during Devonian to Middle Triassic Period by incorporating the basin with the peripheral Micangshan Mountains, the Dabashan Mountains, and the Longmenshan Mountains. The paper uses the sedimentary-fill and the structural deformation analyses as the basic methods to explore alternatively the structural deformation processes during the oceanic plate subduction, the foreland thrusting during continental collision, and the overthrusting during the continental underplating by incorporating the isotopic, paleo-ecological, fault chronologic, and the sediment source analytical data. On the basis of the filtrating analysis of the structural deformation, the paper is to discuss the characteristics and the mechanism of the structural deformation, the superimposed geologic framework and the preservation status of the northern margin of the Sichuan craton. By exploring the basic conditions that control the factors and the processes for oil and gas pool formation, the paper is to address the controlling geologic factors for marine oil and gas occurrence in itself, and to speculate the new targets for petroleum exploration in the area.

AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009