The Style Distribution and Hydrocarbon Accumulation of Inverted Structures in Zhu-3Depression

Two inverted structures were developed in Zhu-3Depression under the dextral transtensional stress from Oligocene.Through fine interpretation of full-area coverage high quality 3Dseismic data,the dynamical genesis,structural styles,and distribution of the two inverted structures were analyzed by adopting structural interpretation method and based on stress field evolution and tectonic evolution analysis.The study results showed that two inverted structural zones were developed in the western and southern fault blocks of Zhu-3Depression.The inverted structures were divided into two types and five subclasses.In combination with the result of well drilled in the inverted structural zones,the significance of the two inverted structures to the hydrocarbon accumulation was analyzed.Study shows that the two inverted structures both have constructive and destructive effects on hydrocarbon accumulation.The first inverted structure is favorable for primary oil reservoir accumulation,while the second inverted structure is favorable for primary gas reservoir accumulation,and also favorable for secondary oil and gas reservoir accumulation.