地幔柱假说及其发展

THE HYPOTHESIS OF MANTLE PLUMES AND ITS DEVELOPMENT

Ｍｏｒｇａｎ提出地幔柱假说之后，基于流体力学基本方程组的定常地幔柱模式研究，认为地幔柱是地幔对流的一个组成部分。组分差异驱动的地幔柱模拟实验结果，限制了地幔柱在地球动力学中的应用。热浮力驱动的模拟实验结果得到了新的动态地幔柱模式。动态地幔柱可以解释有关大陆大片玄武岩和海洋火山链的观测结果。地幔柱携带的热量和浮力，以及各种深度上的地幔物质是岩石圈演化动力过程研究中必须考虑的因素，对解释板块内部发生的中小尺度的动力过程将起重要作用。

After Morgan proposed the hypothesis of mantle plume, steady plume was considered as a part of mantle convection in studies based on basic egustions of fluid dynamics.Results derived from laboratory experiments on plumes driven by buoyancy resulting from compositional differences betweem the plume source layer and overlying material have only restricted application in investigations of geodynamics. From results of experiments on thermally driven plumes it has led to a new model of starting plumes in the Earth′s mantle. This model appears to explain a wide range of observations relating to continental flood basalts and oceanic volcanic(or hotspot) chains. Heat, buoyancy and material from various level in the mantle carried by the mantle plumes are key factors which must be introduced into investigations of dynamical processes in lithospherical evolution. These factors would also play an important role in explaining some dymanical processes which occur in intraplates and have moderate or small scale.