【摘要】 基于山东地区1970—2012年5月387次中小地震震源机制解数据,使用Gephart和Forsyth的FMSI方法计算了该区的平均构造应力方向;使用区域应力张量阻尼反演方法,结合共轭梯度法求解了应力张量的阻尼最小二乘最优化问题,并根据Lund和Townend推导给出的由构造应力张量计算最大水平主应力方向的公式,反演计算了山东地区构造应力场的空间分布特征,并讨论了该区构造应力场的变化及其与郯庐断裂带的关系.更多还原

【Abstract】 Based on 387 focal mechanism solutions of middle and small earthquakes occurred from 1970to 2012,this paper studies the stress field in Shandong region by using damped regional-scale stress inversion.We adapted the conjugate gradient method to solve the damped optimization problem of stress tensors.According to the formulae derived by Lund and Townend we calculated the maximum horizontal principal stress orientations in this region.We also discussed the relationship between spatial variation of regional stress field and the Tancheng——Lujiang fault zone.更多还原