摘要

The mantle plume is the most likely cause for the formation of Large Igneous Provinces (LIPs), and its interaction with the lithosphere can affect the tectonic evolution of the crust and upper mantle. This study focuses on the melting process of mantle plume-lithosphere interaction. On the basis of mass, momentum and energy conservation equations, and material's rheological relation, as well as different melt depletions, using the open-source finite-element code "Ellipsis3D", we firstly perform numerical simulation in the melting process of plume-lithosphere interactions. The results show that there are three stages of this process. At the first stage, the mantle plume melts itself mainly through decompression melting. At the second stage, the mantle plume mostly interacts with the lithosphere in Z direction. In this stage, mantle lithosphere begins to melt because of temperature rising and mantle plume keeps on decompression melting. At the last stage, the mantle plume begins to move horizontally along X direction. As a result of temperature rising, the melting range of the mantle lithosphere increases gradually along with the plume spreading. At the same time, the melting degree of the plume itself decreases because of heat transfer. Then such simulation is made to the Emeishan Large Igneous Province (ELIP), and the results are largely in accordance with previous work. Finally, this paper discusses the formation and evolution of the ELIP based on this numerical simulation and data from field investigations.

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