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

• 作者: Weidong Sun Charles H.Langmuir Neil M.Ribe Lipeng Zhang Saijun Sun He Li Congying Li Weiming Fan Paul J.Tackley Patrick Sanan
• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2021,（16）
• 所属期刊栏目: ARTICLES
• 页码范围: 1691-1697
• 页数: 7页
• 语种: 英文

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 mod-eling 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,mag-matic 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 expres-sion 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.