海底高原与俯冲带相互作用的地质效应的研究进展  

Research Advances on the Geological Effects of the Interaction of Oceanic Plateau with Subduction Zone

作　　者：闫施帅 鄢全树 石学法 袁龙 YAN Shishuai;YAN Quanshu;SHI Xuefa;YUAN Long(Key Laboratory of Marine Geology and Metallogeny,First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China;College of Oceanography,Hohai University,Nanjing 210098,China;Key Laboratory of Deep Sea Mineral Resources Development,Shandong(Preparatory),Qingdao 266061,China)

机构地区：[1]自然资源部第一海洋研究所海洋地质与成矿作用重点实验室,山东青岛266061 [2]河海大学海洋学院,江苏南京210098 [3]山东省深海矿产资源开发重点实验室(筹),山东青岛266061

出　　处：《地球科学进展》2024年第7期702-716,共15页Advances in Earth Science

基　　金：崂山实验室科技创新项目(编号:LSKJ202204103);山东省泰山学者建设工程项目(编号:tstp20230643)资助。

摘　　要：全球俯冲汇聚系统中,俯冲输入组分包括正常大洋板块以及具浮力的海底高原等正地形,二者对俯冲带会产生迥异的地质效应,因此,深入开展海底高原与俯冲带相互作用研究对理解俯冲带地球动力学过程和陆壳侧向增生等地质过程具有重要意义。系统总结了一些目前正处于关键俯冲带处的典型海底高原的地质与地球物理特征,结合俯冲带特征及数值模拟成果,深入探讨海底高原与俯冲带相互作用的地质效应。在俯冲带运动学和几何学方面,位于俯冲前缘的具浮力的海底高原等正地形通常会抵制俯冲,并可能造成俯冲带后撤和俯冲极性反转并形成新的俯冲带,甚至可能会终止俯冲并增生于成熟岛弧/陆壳边缘。然而,近年来的研究显示,部分海底高原的俯冲行为并没有终止,而是俯冲角度变缓呈现平板俯冲的样式,从而造成俯冲带地区上覆板块的构造缩短与增厚以及岩浆活动逐渐向板内迁移。在岩石地球化学方面,具富集地球化学特征的海底高原的俯冲消减不仅影响着壳幔圈层相互作用过程、岛弧—弧后熔岩的地球化学组分以及俯冲带地区热液矿床的形成,而且这些地质体的深俯冲也将对地幔不均一性的形成作出重要贡献。最后,指出未来会在海底高原深部精细结构及演化,岛弧及弧后盆地对“海底高原—海沟”新俯冲构造格局的地质响应,以及控制海底高原发生俯冲/增生的因素及其之间的定量关系等方面有较大的发展潜力。In global subduction systems,the subduction inputs include normal oceanic slabs and buoyant oceanic plateaus.Both exert different geological effects on subduction zones.Thus,studying the interactions among the oceanic plateau and subduction zone will be significant for understanding subduction zone geodynamics and the lateral accretion processes of the continental crust.This study summarizes the geological and geophysical characteristics of typical oceanic plateaus that are currently close to subduction zones.These,combined with the geological and geophysical features of adjacent subduction zones and recent numerical simulation data,are used to discuss the geological effects of the interaction between oceanic plateaus and subduction zones.In terms of kinematics and geometry,buoyant oceanic plateaus generally resist subduction,leading to subduction retreatment and the reversal of subduction polarity,thereby forming new subduction zones.The subduction process in some subduction zones is terminated by the arrival of oceanic plateaus,and the plateaus finally accrete to the mature arc/crustal margins and become part of the continental crust.However,recent studies have shown that part of the oceanic plateaus do not lead to the termination of the subduction process,but rather contribute to the occurrence of flat subduction,thereby resulting in tectonic shortening and the thickening of the overlying plate in the subduction zone area and the gradual migration of magmatic activity toward the intraplate setting.Geochemically,these oceanic plateaus with enriched compositions not only affect subduction zone lava geochemistry and the formation of hydrothermal deposits,but may also contribute to the formation of mantle heterogeneity.Finally,this study proposes some key scientific issues on the interaction of oceanic plateaus with subduction zones,including the detailed crust/mantle structure of subduction zones,the geological and geochemical response of the island arc and backarc basin to the new subduction tectonic framework o

关 键 词：海底高原 俯冲带 地质效应 岩浆作用 

分 类 号：P736.1[天文地球—海洋地质]