Self‐consistent generation of tectonic plates in time‐dependent, three‐dimensional mantle convection simulations
Self‐consistent generation of tectonic plates in time‐dependent, three‐dimensional mantle convection simulations
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DOI：
10.1029/2000gc000036
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发表时间：
2000-08
期刊：
影响因子：
3.7
通讯作者：
P. Tackley
中科院分区：
文献类型：
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作者：
P. Tackley
这里介绍的是地幔对流的自洽三维模拟，其中一些显示了在空间和时间上连续的板块构造行为的近似值。板行为是通过硅酸盐变形的合理材料描述而产生的，简单的屈服应力足以给出一阶板状行为；然而，所需的屈服强度或断层摩擦系数远小于实验确定的值。环形：极向比值在地质观察的限度内。系统地研究了系统对屈服强度的敏感性和强度包络线的形式。在较窄的屈服强度范围内获得最佳板特性，低于该范围可观察到扩散边界，高于该范围可观察到偶发行为，并最终观察到刚性盖。具有移动盖的模型开发出非常长的波长水平结构，这是该域中可能的最长波长。二维模型比三维模型表现出更大的时间依赖性。
Presented here are self‐consistent, three‐dimensional simulations of mantle convection, some of which display an approximation of plate tectonic behavior that is continuous in space and time. Plate behavior arises through a reasonable material description of silicate deformation, with a simple yield stress being sufficient to give first‐order plate‐like behavior; however, the required yield strength or fault frictional coefficient is much less than experimentally determined values. Toroidal:poloidal ratios are within geologically observed limits. The sensitivity of the system to yield strength and the form of strength envelope is systematically investigated. Optimum plate character is obtained in a narrow range of yield strength, below which diffuse boundaries, and above which episodic behavior, and eventually a rigid lid, are observed. Models with mobile lids develop very long wavelength horizontal structure, the longest wavelength possible in the domain. Two‐dimensional models display much greater time dependence than three‐dimensional models.