Sandbox models of relay ramp structure and evolution
Sandbox models of relay ramp structure and evolution
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DOI：
10.1016/j.jsg.2004.09.004
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发表时间：
2005-03
影响因子：
3.1
通讯作者：
R. Hus;V. Acocella;R. Funiciello;M. Batist
中科院分区：
文献类型：
--
作者：
R. Hus;V. Acocella;R. Funiciello;M. Batist
中继斜坡是在正断层系统发育过程中形成的一个共同特征。我们进行了模拟实验，以调查中继坡道的结构和演变。延伸的橡胶板在填砂的底部引起延伸（脆性地壳模拟）。橡胶和沙子之间的硅橡胶条控制断层成核的位置。我们测试的作用，故障间距，故障长度，重叠长度和故障走向的继电器坡道的演变。模拟的中继坡道演化分为三个阶段，其特征在于正断层的生长，它们的相互作用和联系。只有当两个相互作用的断层的总长度大于其间距的8倍时，才发生相互作用和连锁。互动阶段中继坡道的长宽比显示出首选的几何形状，集中在三个左右。在连接阶段之前和之后都观察到故障尖端的传播。在不同的尺度下，模拟的中继坡道的重叠长度和间距关系与自然界中的相似，并且可以使用现有的力学模型来解释。然而，之前没有描述故障尖端在链接之后的进一步传播。
Relay ramps are a common feature formed during the growth of normal fault systems. We performed analogue experiments to investigate the structure and evolution of relay ramps. An extending rubber sheet induces extension at the base of a sand pack (brittle crust analogue). Silicone bars between the rubber and the sand control the location of fault nucleation. We tested the role of fault spacing, fault length, overlap length and fault strike in the evolution of relay ramps. The modelled relay ramps evolved in three stages, characterized by the growth of the normal faults, their interaction and linkage. Interaction and linkage occurred only when the combined length of the two interacting faults was larger than eight times their spacing. The length to width ratio of the relay ramps during the interaction stage showed preferred geometries, clustering around three. The propagation of the fault tips was observed both before and after the linkage stage. Overlap length and spacing relations of the modelled relay ramps are similar to those in nature, at different scales, and can be explained using existing mechanical models. Nevertheless, the further propagation of the fault tips after linkage has not been described previously.