孙吴-嘉荫盆地孙吴断陷重磁研究进展

Research Progress of Gravity and Magnetic of Sunwu Fault-depressionin Sunwu-Jiayin Basin

利用新采集、处理和解释的重磁资料,结合钻井和区域露头资料,对孙吴断陷基底深度、构造格局和油气勘探有利区进行了研究。重磁研究基底深度一般在(100—3 000)m之间,最大深度为3 000 m,基底形态呈东浅西深,岩性主要由古生代变质岩和海西期花岗岩组成,主要发育近NNE和NEE两组断裂,共计28条,具有三凹两凸的构造格局。通过对孙吴断陷内各断凹的规模、断陷期地层沉积厚度、基底顶面埋深以及石油地质条件的综合分析认为腰屯凹陷是下步勘探的有利地区。

In order to research the basement depth,tectonic framework and petroleum exploration conditions of Sunwu fault-Depression,the gravity and magnetic datas are used that are new collected,processed and interpreted,combined with drilling and outcrop data of this region.The basement depth of Sunwu Fault-depression is between 100 m to 3 000 m,the maximum depth is 3 000 m and the basement structural form shown that the west is deeper than the east.The basement are mainly made up of Paleozoic metamorphic rock and Hercynian granite.It mainly developed two series faults which are to near NNE and NEE trend in the Sunwu Fault-depression and the total is 28.The Sunwu-Jiayin Fault-depression could be divided into three sags sandwiched in two convexes.According to the evaluation of the petroleum geological condition,the sedimentary thickness at faulting depression stage,the basement top depth and the scale of the sags,that is forecasted the Yaotun Sag should be potential exploration area.