A STUDY ON HYDROCARBON MIGRATION AND ACCUMULATION IN YANCHANG AREA OF THE ORDOS BASIN
鄂尔多斯盆地延长矿区油气运移成藏研究

The Yanchang formation(Triassic) in the Ordos basin is the reservoir sandstone of the low porosity and low permeability.How has the hydrocarbon produced by the source of the Member 7 migrated to compact reservoir? What are the dynamic power and pathways for migration? These questions constitute long-term focuses.The article has adopted the methods of compaction research and palaeohydrodynamic modeling.Overpressure of Member 1 to 6 of Yanchang Formation has been resumed.Distributions and evolution of petroleum potential of Member 2 and 6 have been analyzed.Based on preterit results of research,the conclusion has been drew that overpressure was the dynamic power of first hydrocarbon migration.Finally from the point of view of hydrocarbon migration three oil models of reservoir formation,which includes handy accumulation,migration along the same layer and through several layers,have been put forward in Yanchang area.