雁荡山世界地质公园火山岩年代学研究  

Chronologic Study on Volcanic Rocks in the Mt.Yandangshan World Geopark

作　　者：余明刚[1] 邢光福[1] 沈加林[1] 陈荣[1] 周宇章[1] 隗合明[2] 陶奎元[1] 

机构地区：[1]南京地质矿产研究所,210016 [2]长安大学地球科学系,西安710054

出　　处：《地质学报》2006年第11期1683-1690,共8页Acta Geologica Sinica

基　　金：国土资源部国土资源大调查项目(编号1212010610611);国土资源部"百人计划"第三批资助项目资助的成果

摘　　要：雁荡山是中国第一个以中生代火山为主题的世界地质公园。长期以来．关于雁荡山火山岩时代及其层位归属存在争议。为了配合世界地质公园的申报、建设并提高其科学研究程度，笔者等对雁荡山火山岩开展了系统的同位素年代学研究。自下而上3个火山地层单元的锆石SHRIMPU—Pb年龄测定表明，雁荡山火山岩的形成时代为97．2～105．6Ma。属于早白垩世晚期；经区域地层对比．确定其层位应归属永康群小平田组，这为整个浙东、乃至与闽东之间的晚中生代火山-沉积地层系统划分与对比，提供了重要地质依据。The Mt. Yandangshan is the first World Geopark which is characteristic of Mesozoic volcano in China. There have had long-term disputions about ages and stratigraphic division of the Mt. Yandangshan volcanic rocks. To cooperate the application and construction of this World Geopark, and enhance its scientific study degree, we put up chronological datings for the Mt. Yandangshan volcanic rocks. Ziron SHRIMP U-Pb datings of three volcanic units from lower to upper indicate that the Mt. Yandangshan volcanic rocks are 97.2- 105.6 Ma in age, i.e. , late stage of Early Cretaceous. Combined with stratigraphic comparison, their strata are inferred to be the Xiaopintian Formation of the Yongkang Group in southeastern Zhejiang. It offers key information for regional subdivision and comparison of Late Mesozoic volcano-sedimentary strata in eastern Zhejiang as well as eastern Fujian.

关 键 词：锆石 SHRIMP测年 火山岩 世界地质公园 雁荡山 浙东南 

分 类 号：P588.14[天文地球—岩石学]