Tarduno John, Bunge Hans-Peter, Sleep Norm, Hansen Ulrich
Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, USA.
Science. 2009 Apr 3;324(5923):50-3. doi: 10.1126/science.1161256.
Bends in volcanic hotspot lineaments, best represented by the large elbow in the Hawaiian-Emperor chain, were thought to directly record changes in plate motion. Several lines of geophysical inquiry now suggest that a change in the locus of upwelling in the mantle induced by mantle dynamics causes bends in hotspot tracks. Inverse modeling suggests that although deep flow near the core-mantle boundary may have played a role in the Hawaiian-Emperor bend, capture of a plume by a ridge, followed by changes in sub-Pacific mantle flow, can better explain the observations. Thus, hotspot tracks can reveal patterns of past mantle circulation.
火山热点线性构造中的弯曲，以夏威夷-帝王海山链中的大转弯最为典型，曾被认为是板块运动变化的直接记录。现在，几条地球物理研究线索表明，地幔动力学引起的地幔上升流位置变化导致了热点轨迹的弯曲。反演模型表明，尽管核幔边界附近的深部流动可能在夏威夷-帝王海山链的转弯中起到了作用，但洋中脊捕获地幔柱，随后太平洋下的地幔流动发生变化，能更好地解释这些观测结果。因此，热点轨迹可以揭示过去地幔环流的模式。
