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用中国地壳运动观测网络区域站在海原断裂带附近的所有观测数据及跨断裂GPS剖面观测数据作为约束,用Smith3D体力模型反演了海原断裂带断层滑动速率和断层闭锁深度,计算了库仑应力积累率和地震矩积累率.采用遗传算法拟合GPS水平运动速度场,拟合的最后残差均方根为1.2mm/a.反演结果为:第一段毛毛山断裂左旋走滑运动速率为3.6mm/a,闭锁深度为22km;第二段老虎山断裂左旋走滑速率为10.5mm/a,闭锁深度为11.4km;第三、四、五段(海原断裂带西段、中段和东段)滑动速率依次为3.5mm/a、5.8mm/a、5.7mm/a,闭锁深度依次为8.5km、3.6km、4.3km.海原断裂带库仑应力积累率为0.48～1.59MPa/100a,毛毛山断裂地震矩积累率较大,但库仑应力积累率较小;老虎山断裂库仑应力积累率和地震矩积累率均比较大;海原断裂带(狭义)中西段库仑应力积累率最大.
Taking all the observation data of the crustal movement observation network area in the vicinity of the Haiyuan fault zone and the cross-fracture GPS profile observation data as constraints, the Smith3D physical model was used to invert the fault slip rate and the depth of fault blockage in the Haiyuan fault zone. The Coulomb stress accumulation Rate and seismic moment accumulation rate.The genetic algorithm was used to fit the horizontal velocity field of GPS, and the root mean square of the final residual error was 1.2mm / a. The inversion result was that the left-lateral strike-slip velocity of the Maochaoshan fault in the first stage was 3.6mm / a, and the latching depth is 22km. The left-lateral slip rate of the second section of Laohushan fault is 10.5mm / a and the latching depth is 11.4km. The third, fourth and fifth sections (the western, middle and eastern sections of Haiyuan fault) ) Sliding velocities were 3.5mm / a, 5.8mm / a and 5.7mm / a respectively, and the latching depths were 8.5km, 3.6km and 4.3km, respectively. The Coulomb stress accumulation rate of Haiyuan fault zone was 0.48 ~ 1.59MPa / But the Coulomb stress accumulation rate is small. The Coulomb stress accumulation rate and seismic moment accumulation rate of Laoshan fault are relatively large. The Coulomb stress accumulation rate is the highest in the middle and western parts of Haiyuan fault zone (narrow sense).