Abstract:

         JZS oilfield, which is located in the middle-northern part of Liaoxi lower uplift, is bounded by  Liaoxi No.1 and Liaoxi No.2 faults in the west. Whether hydrocarbons generated in Liaoxi depression could migrate to Liaoxi lower uplift was directly determined by the carrying capabilities of the two margin faults. So, research on the carrying capabilities of the margin faults is of magnitude significance for understanding hydrocarbon accumulations and making wise decisions for exploration in the region. In this paper, based on the well and 3D seismic data of JZS structure, the history of faulting movement, transversal and vertical sealing abilities during the period of JZS hydrocarbon accumulation of the two margin faults were studied by employing technologies such as tectonic evolution sections, mudstone smearing factors and pressure analysis on fault plane. Research results showed that, during the period of JZS hydrocarbon accumulation which was the final stage of the 1st member of Dongying Formation, Liaoxi No.1 and Liaoxi No.2 faults were active, opened traversely in the 3rd member of Shahejie Formation and vertically above 1,800 m, so they served as a migration conduit system for hydrocarbons generated in Liaoxi depression and migrating to Liaoxi lower uplift. 

Key words: Liaodong Bay, JZS oilfield, fault, carrying capability, hydrocarbon accumulation