震源参数对断层破裂频率依赖性影响分析OA

To investigate the influence of focal parameters,namely focal depth and fault dip angle,on the frequency dependence of fault rupture in MW 6.5-6.9 shallow earthquakes,based on similar epicenters records of subduction zone reverse fault earthquake,the distribution of low-frequency slip on the fault plane is calculated using an iterative deconvolution and superposition finite fault inversion method,and the distribution of high-frequency energy sources is obtained by back projection method.By comparing the distribution characteristics of high-frequency energy sources on the horizontal plane and low-frequency slip on the fault plane,the influence of focal depth and fault dip angle on the frequency dependence of fault rupture is revealed.The results show that(1)both the dip angle of the fault and the focal depth have an impact on the frequency dependence of earthquake fault rupture for subduction zone thrust fault earthquakes;(2)The fault dip angle affects the low-frequency slip distribution of the fault plane;(3)For earth-quakes with low angle fault,the distribution of low-frequency slip on the fault plane is more concentrated,while for earthquakes with high angle fault,the distribution of low-frequency slip on the fault plane is more dispersed;(4)The focal depth mainly affects the distribution of high-frequency energy sources,while when the earthquake focal is shallow,high-frequency energy sources mainly appear at the lower edge of the low-frequency slip zone;(5)As the increase of focal depth,high-frequency energy sources appear on both the upper and lower edges of the low-frequency slip zone on the fault plane.