中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Origin of the LLSVPs at the base of the mantle is a consequence of plate tectonics——A petrological and geochemical perspective

文献类型:CNKI期刊论文

作者Yaoling Niu
发表日期2018-09-06
出处Geoscience Frontiers
关键词LLSVPs Subducted ocean crust Subducted mantle lithosphere No superplumes Mantle chemical differentiation Optimal momentum of inertia
英文摘要In studying the petrogenesis of intra-plate ocean island basalts(OIB) associated with hotspots or mantle plumes, we hypothesized that the two large-low-shear-wave-velocity provinces(LLSVPs) at the base of the mantle beneath the Pacific(Jason) and Africa(Tuzo) are piles of subducted ocean crust(SOC)accumulated over Earth's history. This hypothesis was formulated using petrology, geochemistry and mineral physics in the context of plate tectonics and mantle circulation. Because the current debate on the origin of the LLSVPs is limited to the geophysical community and modelling discipline and because it is apparent that such debate cannot be resolved without considering relevant petrological and geochemical information, it is my motivation here to objectively discuss such information in a readily accessible manner with new perspectives in light of most recent discoveries. The hypothesis has the following elements:(1) subduction of the ocean crust of basaltic composition to the lower mantle is irreversible because(2) SOC is denser than the ambience of peridotitic composition under lower mantle conditions in both solid state and liquid form;(3) this understanding differs from the widespread view that OIB come from ancient SOC that returns from the lower mantle by mantle plumes, but is fully consistent with the understanding that OIB is not derived from SOC because SOC is chemically and isotopically too depleted to meet the requirement for any known OIB suite on Earth;(4) SOC is thus the best candidate for the LLSVPs, which are, in turn, the permanent graveyard of SOC;(5) the LLSVPs act as thermal insulators, making core-heating induced mantle diapirs or plumes initiated at their edges, which explains why the large igneous provinces(LIPs) are associated with the edges of the LLSVPs;(6) the antipodal positioning of Jason and Tuzo represents the optimal momentum of inertia, which explains why the LLSVPs are stable in the spinning Earth.
文献子类CNKI期刊论文
资助机构supported by the National Natural Science Foundation of China (Grant Nos. 41630968, 41130314 and 91014003) ; the National Natural Science Foundation of Chinae Shandong (Grant No. U1606401) ; Qingdao National Laboratory for Marine Science and Technology (Grant No. 2015ASKJ03) ; grants from regional and local authorities (Shandong Province and City of Qingdao), Chinese Academy of Sciences (Innovation Grant No. Y42217101L) ; China University of Geosciences (Beijing)
v.9期:05页:10-23
语种英文;
分类号P588.145
ISSN号1674-9871
源URL[http://ir.qdio.ac.cn/handle/337002/188843]  
专题中国科学院海洋研究所
作者单位1.ChinaUniversityofGeosciences
2.DepartmentofEarthSciences,DurhamUniversity
3.LaboratoryforMarineGeology,QingdaoNationalLaboratoryforMarineScienceandTechnology
4.InstituteofOceanology,ChineseAcademyofSciences
推荐引用方式
GB/T 7714
Yaoling Niu. Origin of the LLSVPs at the base of the mantle is a consequence of plate tectonics——A petrological and geochemical perspective. 2018.

入库方式: OAI收割

来源:海洋研究所

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。