造山带板内洋岛-海山残片的识别及地质意义  

Identification Method and Geological Significance of Intraplate Ocean Island-Seamount Fragments in Orogenic Belt

作　　者：范建军[1] 李才[1] 牛耀龄 解超明[1] 王明[1] Fan Jianjun;Li Cai;Niu Yaoling;Xie Chaoming;Wang Ming(College of Earth Sciences,Jilin University,Changchun 130061,China;Department of Earth Science,Durham University,Durham DH13LE,UK)

机构地区：[1]吉林大学地球科学学院,吉林长春130061 [2]Department of Earth Science,Durham University,Durham DH13LE,UK

出　　处：《地球科学》2021年第2期381-404,共24页Earth Science

基　　金：国家自然科学基金项目(No.41972236);第二次青藏高原综合科学考察(No.2019QZKK0703);自然资源部东北亚矿产资源评价重点实验室自主课题(No.DBY-ZZ-18-04)。

摘　　要：板内洋岛-海山残片是造山带"洋壳残片"的重要组成部分,对恢复造山带所代表的古洋盆的构造演化具有重要意义.然而,如何在造山带中识别板内洋岛-海山残片并通过其恢复古洋盆的构造演化等问题并不清楚.在综述现今板内洋岛-海山的岩石层序、岩浆岩类型、地球化学和同位素特征等的基础上,结合对青藏高原班公湖-怒江缝合带数个板内洋岛-海山残片研究的成果,初步总结了造山带板内洋岛-海山残片的识别标志及其地质意义、时代的确定方法等基础地质问题.板内洋岛-海山记录了丰富的洋盆演化信息,且是大洋俯冲消亡时最易保存的地质体.因此,在古洋盆构造演化的恢复中,对造山带板内洋岛-海山残片的研究至关重要.Fragments of intraplate ocean island-seamount are important parts of"oceanic crust fragments"in the orogenic belt,and these fragments place important constraints on restoring the tectonic evolution of the ancient ocean basin represented by the orogenic belt.However,the identification method and geological significance of the intraplate ocean island-seamount fragments in the orogenic belt are poorly known.Based on the review of the lithological sequence,magmatic rock types,geochemistry,and isotopic characteristics of the intraplate ocean island-seamounts in the modern ocean basin and our research results on several intraplate ocean island-seamount fragments in the Bangongco-Nujiang suture zone in the Tibetan Plateau,in this study it summarizes the identification method,age determination method,and geological significance of the intraplate ocean islandseamount fragments in the orogenic belt.Intraplate ocean island-seamounts record extensive information about the tectonic evolution of the ocean basin,and these are the easiest oceanic geological bodies to preserve during the subduction of the oceanic lithosphere.Therefore,studies on the intraplate ocean island-seamount fragments in the orogenic belt are very important in restoring the tectonic evolution of the ancient ocean basin.

关 键 词：造山带 板内洋岛-海山残片 班公湖-怒江缝合带 地质年代学 地球化学 

分 类 号：P54[天文地球—构造地质学]