Inversion of fault data with low diversity for stress: Principles and applications
Inversion of fault data with low diversity for stress: Principles and applications
复制标题
DOI：
10.1016/j.jsg.2015.06.001
复制
发表时间：
2015-08
影响因子：
3.1
通讯作者：
Y. Shan;Xinquan Liang
中科院分区：
文献类型：
--
作者：
Y. Shan;Xinquan Liang
虽然最少需要四个独立的单相故障数据来解决一个独特的减少应力张量，我们在本文中证明，在某些情况下，少量的故障数据是足够的解决部分减少应力张量。其中一个主应力方向可以由断层面上具有共同零剪切方向的两个断层或断层面的主应力平面中具有共同相交点的三个断层确定。该方向与断层资料相结合，确定了其他主应力方向的可能范围。确定方向是最大、中间还是最小主应力取决于滑动趋势或更多断层数据提供的约束。这种方法也可以应用于一组四个或更多的故障数据与低方向多样性。最后将此新方法应用于台湾西部车笼埔断层沿着两组断层资料。从该方法确定的应力方向位于可接受的范围内的最大/最小主应力使用其他现有的和可比的方法，如右二面体/三面体的方法。他们不同适度的最大/最小主应力方向相比，断层运动学分析的矩张量法。新方法在应力估计精度和应力估计不依赖于少数不平行于优势断层集的断层方面优于正二面体/正三面体方法。
Although a minimum of four independent, single-phase fault data are required to solve for a unique reduced stress tensor, we prove in this paper that a smaller number of fault data are sufficient in some instances to solve for part of the reduced stress tensor. One of the principal stress directions is determinable from either two faults with a common null shear direction on the fault planes or three faults with a common intersection in a principal stress plane of the fault planes. This direction is combined with the fault data to determine the possible ranges of other principal stress directions. Determining whether the direction is for the maximum, intermediate or minimum principal stress depends upon constraints provided by slip tendency or more fault data. This approach can also be applied to a set of four or more fault data with low orientation diversity. This new method is finally applied to two different sets of fault data from along the active Chelungpu fault, western Taiwan. The stress orientations determined from the method lie in acceptable ranges for the maximum/minimum principal stresses using other existing and comparable methods, such as the right dihedra/trihedra methods. They differ moderately in the maximum/minimum principal stress directions when compared to the moment tensor method for fault kinematic analysis. The new method has advantages over the right dihedra/trihedra methods in the accuracy of stress estimate and the independence of stress estimate upon the small number of faults that are not parallel to the dominant fault set(s).