Tectonic evolution of convergent plate margins and its geological effects  

作　　者：Yongfei ZHENG Yixiang CHEN Renxu CHEN Liqun DAI 

机构地区：[1]CAS Key Laboratory of Crust and Mantle Materials and Environments,School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China

出　　处：《Science China Earth Sciences》2022年第7期1247-1276,共30页中国科学（地球科学英文版）

基　　金：the project on the development strategy of subduction zones that was supported not only by a fund from the Chinese Academy of Sciences(2015-2016);by a joint fund from the National Natural Science Foundation of China and the Chinese Academy of Sciences(2018-2019);supported by the National Natural Science Foundation of China(Grant No.92155306)。

摘　　要：Oceanic lithosphere is generated at divergent plate boundaries and disappears at convergent plate boundaries.Seafloor spreading and plate subduction together constitute the physical coupling and mass conservation relationships to the movement of lithospheres on Earth.Subduction zones are a key site for the transfer of both matter and energy at converging plate boundaries,and their study has been the hot spot and frontier of Earth system science since the development of plate tectonics theory.As far as the dynamic regime and geothermal gradient of convergent plate margins are concerned,they have different properties in different stages of the subduction zone evolution.In general,the early low-angle subduction leads to compressional tectonism dominated by low geothermal gradients at the plate interface,and the late high-angle subduction results in extensional tectonism dominated by high geothermal gradients at the plate interface and its hanging wall.Active rifts are produced along suture zones through not only slab rollback or slab breakoff in the terminal stage of oceanic subduction but also foundering and thinning of the lithosphere in the post-subduction stage.Due to the differences and changes in the geometric and thermobaric structures of convergent plate margins,a series of changes in the type of metamorphism and magmatism can occur in active and fossil subduction zones.Dehydration and melting of the subducting oceanic crust are prominent at subarc depths,giving rise to fluids that dissolve different concentrations of fluid-mobile incompatible elements.The subduction zone fluids at subarc depths would chemically react with the overlying mantle wedge peridotite,generating metasomatites as the mantle sources of mafic magmas in oceanic and continental arcs.However,these metasomatites did not partially melt immediately upon the fluid metasomatism to trigger arc magmatism,and they did not melt until they were heated by asthenospheric convection due to rollback of the subducting slab.Therefore,recognition of the c

关 键 词：Plate tectonics Continental geology Convergent margins Continental rifting Subduction zone Orogenic belt 

分 类 号：P542[天文地球—构造地质学]