Analysis of the 1994 Northridge Earthquake Aftershocks Using Micropolar Continuum Theory

9416318 Unruh本研究将分析1994年1月17日北岭地震的余震，以获得分布的孕震变形，并检验盲冲断层上方隆起和褶皱的现有模型。最近对盲冲地震的详细研究表明，断层上盘的显著变形是通过与层面成高角度的小断层上的滑动发生的，而不仅仅是模型所暗示的层面滑动。偏离标准模型的另一个可能的原因是，洛杉矶和圣费尔南多山谷下的逆冲断层植根于结晶基底岩石，而不是模型最初开发的沉积岩。分析将使用地震P和T轴的模式来获得孕震应变率和旋转分量（涡度），然后将其与模型预测进行比较。研究结果将增强对盲冲断层变形的理解，并将检验现有模型在盲冲断层地震中预测地壳行为的能力。

9416318 Unruh This study will analyze the aftershocks of the January 17, 1994 Northridge earthquake to obtain distributed seismogenic deformation and t test existing models of uplift and folding above blind thrust faults. Detailed studies of recent blind thrust earthquakes have shown that significant deformation of the hangingwall of the fault occurs by slip on small faults at a high angle to bedding, and not just by bedding-plane slip as the models imply. Another possible reason for departure from the standard model is that the thrusts beneath the Los Angeles and San Fernando Valleys are rooted in crystalline basement rocks, rather than in sedimentary rocks for which the model was originally developed. The analysis will use patterns of seismic P and T axes to obtain seismogenic strain rates and the rotational component (vorticity), which will then be compared with the model prediction. The results will enhance understanding of deformation associated with blind thrusts, and will be therefore test the ability of the existing models to predict behavior of the crust during blind thrust earthquakes.