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Abstract：
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.
摘要：
夏威夷热点的历史对板块运动和地幔流动的研究具有持久的兴趣，许多研究人员使用夏威夷-皇帝海山链的详细历史进行了调查。这段历史无法解释的方面之一是几个皇帝海山与夏威夷羽流轨迹的明显抵消。在这里，我们表明，根据现有数据，皇帝海山的火山迁移速率与太平洋板块的漂移速率不一致，并表示海山向北，然后向南的“绝对运动”。数值模型表明，移动的扩展脊对羽流上部的吸引和捕获导致羽流岩浆输出在地表的位置变化。羽状物质向山脊的流动导致明治明显向南移动。然后，羽流的上部一直向北运送到65Ma之前。在山脊和羽流充分分离后，岩浆输出返回到羽状茎的中心。这些变化在羽流轨道上的海山体积变化中很明显。来自皇帝海山链的玄武岩的化学和同位素组成从Mei和底特律的贫化（强中洋脊亲和力）变为富集（海洋岛型），支持山脊影响力的下降。尽管其表面表达被地幔流和羽状脊相互作用所改变，夏威夷烟羽的茎在皇帝时期可能基本上是静止的。
