On mantle drag force for the formation of a next supercontinent as estimated from a numerical simulation model of global mantle convection
On mantle drag force for the formation of a next supercontinent as estimated from a numerical simulation model of global mantle convection
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DOI：
10.1111/ter.12380
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发表时间：
2019-02
期刊：
影响因子：
2.4
通讯作者：
Masaki Yoshida
中科院分区：
文献类型：
--
作者：
Masaki Yoshida
模拟三维球面地幔对流，预测未来大陆运动，探讨大陆运动的驱动力。结果表明，下一个超大陆形成所需的时间（从现在算起≥300 Ma）和过程对地幔动力学的关键流变参数的选择很敏感，如上下地幔之间的粘度对比和岩石圈的屈服强度。从本文所研究的所有数值模式来看，在形成新的超大陆的过程中，大陆下方水平地幔流的地幔阻力可能主要作为大陆运动的阻力。作用于移动大陆底部的拉应力和压应力的最大绝对值约为100兆帕，这与典型的板拉力值相当。
Three‐dimensional spherical mantle convection was simulated to predict future continental motion and investigate the driving force of continental motion. Results show that both the time required (≥300 Ma from the present) and the process for the next supercontinent formation are sensitive to the choice of critical rheological parameters for mantle dynamics, such as a viscosity contrast between the upper and lower mantles and a yield strength of the lithosphere. From all the numerical models studied herein, mantle drag force by horizontal mantle flow beneath the continents may mostly act as a resistance force for the continental motion in the process of forming a new supercontinent. The maximum absolute magnitude of the tensional and compressional stress acting at the base of the moving continents is in the order of 100 MPa, which is comparable to a typical value of the slab pull force.