Plume interaction and mantle heterogeneity:A geochemical perspective  

作　　者：Zhen Zhang Sanzhong Li Guangzeng Wang Xiyao Li Gang Wang Yanhui Suo M.Santosh Lingli Guo 

机构地区：[1]Fourth Institute of Oceanography,Ministry of Natural Resources,Beihai 536000,China [2]Key Lab of Submarine Geosciences and Prospecting Techniques,MOE,College of Marine Geosciences,Ocean University of China,Qingdao 266100,China [3]Laboratory for Marine Geology,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266237,China [4]School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China [5]Department of Earth Sciences,University of Adelaide,Adelaide,SA,5005,Australia

出　　处：《Geoscience Frontiers》2020年第5期1571-1579,共9页地学前缘（英文版）

基　　金：The Scientific and Technological Innovation Project Financially Supported by National Science Foundation China(Grant No.91958214);Qingdao National Laboratory for Marine Science and Technology(Grant No.2017ASKJ02);the Fundamental Research Funds for the Central Universities(Grant No.2017062021)provided financial support for this study;the financial supports received from National Natural Science Foundation of China(Grant No.U1606401);National Ocean Bureau Program(GASI-GEOGE-1);the financial supports of Aoshan Elite Scientist Plan(Grant No.2015ASTP-0S10)of Qingdao National Laboratory for Marine Science and Technology to Prof.Sanzhong Li。

摘　　要：Mantle plumes originating from the Core-Mantle Boundary(CMB)or the Mantle Transition Zone(MTZ)play an important role in material transfer through Earth’s interior.The hotspot-related plumes originate through different mechanisms and have diverse processes of material transfer.Both the Morganian plumes and large low shear wave velocity provinces(LLSVPs)are derived from the D"layer in the CMB,whereas the Andersonian plumes originate from the upper mantle.All plumes have a plume head at the Moho,although the LLSVPs have an additional plume head at the MTZ.We compare the geochemical characteristics of various plumes in an attempt to evaluate the material exchange between the plumes and mantle layers.The D"layer,the LLSVPs and the Morganian plumes are consisted of subducted slab and post-perovskite from the lower mantle.Bridgmanite would crystallize during the upwelling process of the LLSVPs and the Morganian plumes in the lower mantle,and the residual is a basalt-trachyte suite.Unlike the Morganian plumes,the crystallization in the LLSVPs is insufficient that material accumulates beneath the MTZ to form a plume head.Typically,the secondary plumes above the plume head occur at the edge of the LLSVPs because it is easier for bridgmanite crystal separating from the plume head at the edge,and the residual material with low density upwells to form the secondary plumes.Meanwhile,Na and K are enriched during the long-term crystallization process,and then the basalt-phonolite suite appears in the LLSVPs.The geochemical characteristics of Andersonian plumes suggest that the basalt-rhyolite suite is the major component in the upper mantle.Meanwhile the basalt-rhyolite suite also appears in the LLSVPs and the Morganian plumes because of the assimilation and contamination in the plume head beneath the Mono.

关 键 词：Mantle plumes Mantle components Geochemical process 

分 类 号：P597.3[天文地球—地球化学]