Plume-ridge interaction induced migration of the Hawaiian-Emperor seamounts  

地幔柱-洋脊相互作用诱导的夏威夷-帝王海山迁移

作　　者：Weidong Sun Charles H.Langmuir Neil MRibe Lipeng Zhang Saijun Sun He Li Congying Li Weiming Fan Paul J.Tackley Patrick Sanan 孙卫东;Charles H.Langmuir;Neil MRibe;张丽鹏;孙赛军;李贺;李聪颖;范蔚茗;Paul J.Tackley;Patrick Sanan(Center of Deep Sea Research,Center of Ocean Mega Science,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China;Laboratory for Marine Mineral Resources,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China;School of Marine Sciences,University of the Chinese Academy of Sciences,Beijing 100049,China;Department of Earth and Planetary Sciences,Harvard University,Cambridge MA 02138,USA;Universite Paris-Saclay,CNRS,Lab FAST,F-91405 Orsay,France;Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences,Beijing 100101,China;Institute of Geophysics,Department of Earth Sciences,ETH Zurich,Zurich CH-8092,Switzerland)

机构地区：[1]Center of Deep Sea Research,Center of Ocean Mega Science,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [2]Laboratory for Marine Mineral Resources,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China [3]School of Marine Sciences,University of the Chinese Academy of Sciences,Beijing 100049,China [4]Department of Earth and Planetary Sciences,Harvard University,Cambridge MA 02138,USA [5]Universite Paris-Saclay,CNRS,Lab FAST,F-91405 Orsay,France [6]Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences,Beijing 100101,China [7]Institute of Geophysics,Department of Earth Sciences,ETH Zurich,Zurich CH-8092,Switzerland

出　　处：《Science Bulletin》2021年第16期1691-1697,M0004,共8页科学通报（英文版）

基　　金：supported by the National Key Research & Development Program of China (2016YFC0600408);the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (XDB18020000);the Programme National de Planétologie (PNP) of the Institut des Sciences de l’Univers (INSU) of the French National Centre for Scientific Research (CNRS),co-funded by the French Space Centre (CNES) (BFC 221950)。

摘　　要：The history of the Hawaiian hotspot is of enduring interest in studies of plate motion and mantle flow,and has been investigated by many researchers using the detailed history of the Hawaiian-Emperor Seamount chain.One of the unexplained aspects of this history is the apparent offset of several Emperor seamounts from the Hawaii plume track.Here we show that the volcanic migration rates of the Emperor seamounts based on existing data are inconsistent with the drifting rate of the Pacific plate,and indicate northward and then southward “absolute movements”of the seamounts.Numerical modeling suggests that attraction and capture of the upper part of the plume by a moving spreading ridge led to variation in the location of the plume’s magmatic output at the surface.Flow of the plume material towards the ridge led to apparent southward movement of Meiji.Then,the upper part of the plume was carried northward until 65 Ma ago.After the ridge and the plume became sufficiently separated,magmatic output moved back to be centered over the plume stem.These changes are apparent in variations in the volume of seamounts along the plume track.Chemical and isotopic compositions of basalt from the Emperor Seamount chain changed from depleted(strong mid-ocean ridge affinity)in Meiji and Detroit to enriched(ocean island type),supporting declining influence from the ridge.Although its surface expression was modified by mantle flow and by plume-ridge interactions,the stem of the Hawaiian plume may have been essentially stationary during the Emperor period.利用帝王海山链不同海山的年龄和相邻海山间的距离获得的板块漂移速度与利用GPlates板块重建获得的结果有很大的差异,说明海山的喷发位置相对于地幔柱发生了迁移.地球化学和地球动力学模拟显示上述现象是地幔柱与洋脊相互作用的结果.在约85 Ma前,太平洋与伊泽纳吉之间的洋脊到达了19°N附近,夏威夷地幔柱此时位于21°N附近.由于地幔柱与洋脊的相互作用,地幔柱上部被吸引向南,在洋脊上喷发,形成梅吉火山.此后约10 Ma,地幔柱随洋脊一起向北漂移,因此底特律海山的喷发纬度变化很大.随着洋脊继续向北迁移,其对地幔柱的影响不断减弱,在75 Ma后,地幔柱上部开始摆脱洋脊的束缚向南迁移.玄武岩组成从梅吉、底特律海山的亏损特征逐渐转为洋岛玄武岩的富集特征.

关 键 词：Pacific plate Emperor-Hawaii chain Plume-ridge interaction GEOCHEMISTRY Numerical modeling 

分 类 号：P736[天文地球—海洋地质]