断层几何形态和自发破裂的动力学参数对地震波场的影响

断层的自发破裂及其产生的地震波场是地震学研究的重要内容.断层几何形态和自发破裂过程中的动力学参数不同,往往会导致不同的震源破裂过程,进而对地震波场产生显著的影响.本文基于不同几何形态的断层上的自发破裂过程,通过计算研究其产生的地震波场的特征.针对弯折和分叉的断层系统,我们考察了初始成核区位置以及超剪切破裂对于地震波场的...

Effects of fault geometry and dynamic parameters of spontaneous rupture on seismic wave field

The spontaneous rupture of faults and its resulting seismic wave field are important subject in seismological research.Different fault geometry and dynamic parameters in the spontaneous rupture process often lead to different rupture processes,which in turn have a significant impact on the seismic wave field.In this work,we computed the spontaneous rupture process on faults with different geometries,and analyzed the characteristics of the corresponding seismic wave field.Two kinds of fault systems which are bending and branching faults are considered.We investigated the impact of the position of the initial nucleation zone and supershear rupture on the seismic wave field for each system separately.The results show that for bending faults,as the bending angle increases,the peak distribution of the seismic wave field changes along the bending direction.Excessive bending angles will depress the seismic wave field.The longer the rupture distance on the faults is,the more energy will be accumulated,which will cause a larger seismic wave field.For branching faults,the branch plane with a smaller angle is more likely to rupture,and the rupture strength is greater,which will cause a stronger seismic wave field.The supershear rupture will also cause a stronger seismic wave field and excite high-frequency components.Obvious pulses can be observed and the permanent displacement will be increased.The results of this study is helpful to understand seismic wave field characteristics and provide more information for further dynamics inversion.