东海西湖凹陷反转构造定量研究:来自裂变径迹分析数据的约束  

QUANTITATIVE STUDY ON INVERSION STRUCTURES IN XIHU DEPRESSION,EAST CHINA SEA: CONSTRAINTS FROM FISSION TRACK ANALYSIS DATA

作　　者：周祖翼[1] 贾健谊 李家彪[3] 杨凤丽[1] 

机构地区：[1]同济大学海洋地质教育部重点实验室,上海200092 [2]中石化新星石油公司上海海洋石油局,上海200120 [3]国家海洋局海底科学重点实验室,杭州310012

出　　处：《海洋地质与第四纪地质》2002年第1期63-67,共5页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目 ( 4 9876 0 13);国家重点基础研究发展规划资助项目 ( G2 0 0 0 0 476 0 4

摘　　要：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 。Fission track analysis is carried out on eleven apatite samples and six zircon samples from five drilling wells(from north to south,wells XL1,XL2,XH,XY and XT)of Xihu depression,East China Sea.The samples are from Oligocene,Miocene and Pliocene strata.The median fission track ages of all zircon samples are older than the respective strata ages,reflecting that the maximum burial temperature is less than(225±25) ℃ for these samples.Apatite fission track ages exhibit a complicate pattern,with FT ages from wells XT and XY in the south larger than and FT ages from wells XH,XL2, XL1 smaller than ages of the respective strata.The distribution of these ages show that the maximum burial depth in the north part of the depression is greater than that in the south,reflecting that the degree of inversion increases northwards.The amount of uplift and erosion is also estimated quantitatively for those wells where apatite fission track ages are smaller than the strata ages.Despite of an integrated analysis of vitrinite reflectance,sonic velocity is required for a good estimation of the amount of erosion for these wells.Our preliminary analysis of FT data shows that the amount of erosion for wells of XH and XL1 is less than 1 786 m.

关 键 词：反转构造 裂变径迹 剥蚀量 西湖凹陷 

分 类 号：P736.15[天文地球—海洋地质]