Study Of Structure Transfer Zones In Liaohe Beach Area

Liaohe beach area which is the stretch of Liaohe basin locates in the northern Liaodong bay basin. It formed during the Mesozoic-Cenozoic period and had experienced two stages: rifting stage and depression stage.Based on the result of structure interpretation, discerned transfer zones of different types and classes in the area. According to the current structure map, analyzed the relationship between transfer zones and petroleum; According to the paleo-constructure maps and depth maps, studied how did transfer zones control the deposition.Through the analysis of structure units and faults, discerned different transfer zones, and according to the ranks of the faults, classified the transfer zones into three classes. The first rank transfer zones include Yueya relay ramp, Xianhe-Haiwaihe relay ramp, Shuangnan sidelong anticline, Gaizhoutan relay ramp and Tai-Kui sidelong anticline; The second rank transfer zones include Yuanyanggou relay ramp, Haiwaihe-Xianhe relay ramp and Longwangmiao relay ramp; The third rank transfer zones are everywhere and consist of small parts between different associated faults in the downdroped brocks of Hainan fault and Yannan faults.Comprehensively analyzed fault system maps,structure characters,and sedimentary systems, concluded that there are three courses for transfer zones. They are paleo-structure, activities of different strength along the main faults and imbalanced extensions. The essence of transfer zones’ evolution is the process from isolated faults to hard links. The evolution of transfer zones in the area are related to the rebirth and newborn of activity. The isolated period correspond to the Shahejie section; The formation period correspond to the Ed3 formation; The complicated and broken period correspond to the Ed2 and Ed1 formation.Transfer zones obviously control the sedimentary systems. They control the water systems, play the role as channels of fragment provenance to basin and then reflect and change the distribution of sedimentary systems. There is also a close relationship between the transfer zone and petroleum: first, transfer zones control the fragment provenance and sedimentary systems, which always become good reserviors. Second, in the process of transfer zones’ formation, it comes out lots of faults and fractures, which provide good channels for petroleum migration ; third, transfer zones are always complicated structure areas, which provide good environments for traps. So those areas in the transfer zones or nearby it are always in rich of hydrocarbon.