Growing Faults in the Lab: Insights Into the Scale Dependence of the Fault Zone Evolution Process
Growing Faults in the Lab: Insights Into the Scale Dependence of the Fault Zone Evolution Process
复制标题
实验室中不断增长的断层：洞察断层带演化过程的尺度依赖性
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
O. Oncken
中科院分区：
文献类型：
--
作者：
Malte C. Ritter;M. Rosenau;O. Oncken
模拟沙盒实验是一种广泛使用的方法，用于研究无法单独从自然数据中解决的构造过程，例如应变局部化和断层带的形成。尽管如此，在沙箱实验中看到的应变局部化和断层带形成的动力学在多大程度上可以外推到自然原型仍然不清楚。动态相似性的最重要的是适当的比例所需的工作，以创建故障系统，Wprop。使用走滑变形的模拟沙箱实验，我们表明Wprop近似与断层系统长度的平方l成比例，这与自然界中断层生长的理论一致。通过对Wprop和应变分布的定量测量，我们能够表明Wprop主要用于局部化之前的扩散变形，因此我们认为这类似于天然断层网络中低于地震分辨率的小规模断层上的分布变形。最后，我们将我们的数据与自然断层带消耗的工作估计进行比较，以验证模拟沙箱实验在能量方面的规模是否合适，也就是说，它们真正动态地扩展。
Analog sandbox experiments are a widely used method to investigate tectonic processes that cannot be resolved from natural data alone, such as strain localization and the formation of fault zones. Despite this, it is still unclear to which extent the dynamics of strain localization and fault zone formation seen in sandbox experiments can be extrapolated to a natural prototype. Of paramount importance for dynamic similarity is the proper scaling of the work required to create the fault system, Wprop. Using analog sandbox experiments of strike‐slip deformation, we show Wprop to scale approximately with the square of the fault system length, l, which is consistent with the theory of fault growth in nature. Through quantitative measurements of both Wprop and strain distribution we are able to show that Wprop is mainly spent on diffuse deformation prior to localization, which we therefore regard as analogous to distributed deformation on small‐scale faults below seismic resolution in natural fault networks. Finally, we compare our data to estimates of the work consumed by natural fault zones to verify that analog sandbox experiments scale properly with respect to energy, that is, that they scale truly dynamically.