东海陆架盆地西湖凹陷东部过XH-1井的GH-1剖面,揭示了盆地边缘在新生代多次盆地原型迭代中的结构变化.在梳理前人关于盆地原型学术观点的基础上,通过T25、T24、T23上超点不断东扩的特征,确认了陆相盆地发展跨越式、旋回性的演化特点;根据T24、T20两期构造反转,确认了陆内迁移拗陷期渐新统、中新统(龙井组和玉泉组)分别为两个二级构造层序;结合柳浪组的成因机制,探讨了柳浪组在盆地发展史中的归属问题.通过玉泉运动、花港运动和龙井运动机制探讨及界面确认,深化了断陷期、拗陷期西湖凹陷东部边界的认识,明确了西湖凹陷经历了古新世—始新世走滑拉张断陷-转换边缘拗陷、渐新世—中新世陆内迁移拗陷、上新世—第四纪弧后陆架边缘拗陷的盆地原型迭代发展史.%The GH-1profile through the Well XH-1revealed the structural changes of basin edge during the Cenozoic basin evolution of the eastern Xihu sag in the East China Sea shelf basin.On the basis of combing with the standpoints of previous research on basin prototype, and reviewing the continuously eastward expansion super points of T25, T24 and T23, the evolution characteristics of leapfrog and cyclic development for continental basins are confirmed.Referring to the two tectonic inversions of T24 and T20, two second-order tectonic sequences are recognized in the intracontinental migration depression period as Oligocene and Miocene (Longjing Formation and Yuquan Formation).Based on the genetic mechanism of Liulang Formation, the attribution of Liulang Formation in the basin development history is discussed.Through the mechanism discussion of the Yuquan, Huagang and Longjing movements and confirmation of their interfaces, the understanding of the east basin edge in fault depression during depression period is deepened:Xihu sag experienced the iterative development of the archetypal basin from strive slip tensional depression to conversion edge depression in PaleoceneEocene, intracontinental migration depression in Oligocene-Miocene, and retro-arc continental shelf margin depression in Pliocene-Quaternary.
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