Neotectonic movements in the Dongpu depression and their controls on hydrocarbon accumulation in shallow reservoirs

The present paper deals with the neotectonic movements in the Dongpu depression from the Palaeogene onwards on the basis of the calculation of erosion thickness and fault displacement, and the controls of the neotectonic movements on the generation, accumulation, migration and timing of the hydrocarbons by means of the examination of the tectonic evolution, geochemical signatures, homogenization temperatures of the inclusions, and isotopic dating. The neotectonic movements in the Dongpu depression took place at the end of the deposition of the Dongying and Minghuazhen Formations, respectively, and were dominated by vertical movements, with slightly extensional faulting. The two phases of neotectonic movements cited above are interpreted to control the secondary hydrocarbon generation in the source rocks and the second infilling in the shallow reservoirs. The hydrocarbons generated in the deeper reservoirs migrated upwards to the shallower reservoirs via the NE-trending basement faults, Dongying Formation sandstones and Neogene EW-trending faults. The Neogene hydrocarbons are mostly constrained by the EW-trending faults.