Multiphase tectonic movements, cap formations and evolution of the Majiang paleo-reservoir

Abstract

The Majiang paleo-reservoir is a typical destroyed hydrocarbon reservoir, buried in carbonate strata of China's southern marine-facies. Field geological explorations, interpretations of seismic profiles and balanced cross-section restorations around this paleo-reservoir reveal that its formation and evolution have been restricted by multiphase tectonic movements of different intensities. A regional tectonic mechanism and model have been suggested for the formation and evolution of the Majiang paleoreservoir. Geological field exploration has been carried out along three typical Silurian cross-sections and rock samples were tested in combination with water-rock interaction. Based on the result of cap tests, the planar distribution, the residual thickness, the erosion thickness and the preservation conditions, the Silurian mudstone cap is discussed around the Majiang paleo-reservoir. Combining the hy drodynamic conditions of its formation and evolution and its tectonic movements, we determined the fact that the thicker the cap is, the more resistant it is to hydrodynamic destruction. The multi-phase formation and destructive geological model of the paleo-reservoir is established through an overall analysis of multiphase tectonic evolutions, cap developments, hydrodynamic conditions and solid mineral metallogenic ages measured by Rb-Sr, Pb and Sm-Nd isotope techniques. © 2011 China University of Petroleum (Beijing) and Springer-Verlag Berlin Heidelberg.