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对来自东海陆架盆地西湖凹陷反转构造带上的 5口钻井 (XL1,XL2 ,XH,XY,XT)的 17个样品 (11个磷灰石、6个锆石样品 )进行了系统的裂变径迹年龄测定。样品的地层年代介于渐新世和上新世之间。锆石裂变径迹年龄表明 ,各样品所经历的最大埋藏温度小于 (2 2 5± 2 5 )℃。磷灰石裂变径迹的年龄则比锆石的要复杂。南侧 XT和XY两口井的磷灰石裂变径迹年龄大于相应的地层年龄 ,而北侧的 3口井的磷灰石裂变径迹年龄则小于相应的地层年龄。磷灰石年龄的分布表明西湖凹陷南部第三系地层所经历的最大沉积埋深小于北部 ,反转程度南弱北强。对于裂变径迹年龄小于地层年龄的样品 ,对地层剥蚀量进行了初步的估算
Seventeen samples (11 apatite and 6 zircon samples) from 5 wells (XL1, XL2, XH, XY and XT) on the inverted structural belt of the Xihu Sag, East China Sea shelf basin were systematically studied. Age determination. The ages of the samples were between Oligocene and Pliocene. Zircon fission track age indicates that the maximum burial temperature experienced by each sample is less than (2 2 5 ± 2 5) ° C. The age of apatite fission track is more complicated than that of zircon. The apatite fission track ages of the XT and XY wells on the south side are larger than the corresponding stratigraphic ages, while the apatite fission track ages of the three wells on the north side are smaller than the corresponding stratigraphic ages. The distribution of apatite ages shows that the maximum buried depth of Tertiary strata experienced in the southern Xihu sag is smaller than that in the north, and the degree of inversion is weak in the south and weak in the north. For the samples whose fission track age is less than the age of the formation, preliminary estimates of formation denudation are made