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本文从东海西湖凹陷的地质构造特征出发，根据西湖凹陷所处的西太平洋特殊地质构造位置，结合反转构造理论，认为自新生代以来，西湖凹陷长期处于太平洋板块向欧亚板块斜向俯冲的挤压状态。随时间的推移凹陷的边界条件不断地变化，由此引起应力场的改变，继而造成构造反转。西湖凹陷曾经历过五次构造反转期。盆地的复合，构造的叠加，断层性质的改变，对油气生成、运移和储集起着决定性的作用。本文最后用反转构造理论对油气远景作了简单的探索。认为早期由正断层形成的地堑、地垒、断块及晚期褶皱、逆断层发育的地区应作为油气勘探的重点。前者，早期局部张应力形成的正断层，在区域压应力的持续作用下，后期虽然在形式上还是正断层，但晚期已转变为压性的，对油气聚集较为有利。后者，由于新生代早期的巨厚沉积，并且发育着张性断裂，这些对油气的生成和运移有一定好处。
Based on the geological tectonics of the West Lake Sag in the East China Sea, according to the special geological structure of the West Pacific Ocean in the Xihu Sag and the reversal tectonic theory, it is considered that the West Lake Sag has been in the oblique subduction of the Pacific Plate to the Eurasian Plate since the Cenozoic Squeeze state. Over time, the boundary conditions of the dimples are continuously changing, thereby causing changes in the stress field, which in turn cause structural inversion. West Lake depression has experienced five structural inversion period. The compounding of the basin, the superposition of the structure and the change of fault nature play a decisive role in the formation, migration and accumulation of oil and gas. At the end of this paper, we simply use the theory of inversion structure to explore the future of oil and gas. It is considered that the early graben, basement, fault block and late fold formed by normal faults should be the focus of oil and gas exploration. The former, the normal faults formed by early local tensional stress, are continuously normalized by the continuous compressive stress in the region, but have been transformed into compressive in the late stage and favorable to hydrocarbon accumulation. The latter, due to the thick deposits of the early Cenozoic and the development of Zhang-Zhang fractures, are of some benefit to hydrocarbon generation and migration.