【摘要】 利用宁夏地震台网记录的宁夏及邻区数字地震波资料,采用Brune(1970)模型,通过几何扩散校正、介质衰减校正、仪器校正等将速度记录谱归算为震源位移谱。使用遗传算法计算拐角频率及零频极限,进而计算震源半径、地震矩等小震震源参数,并系统分析了各种参数之间的关系。使用发生于2003年6月—2007年12月ML1.7~4.4的186次地震事件估算的震源参数表明:地震矩、近震震级、破裂半径、拐角频率等之间可以拟合为对数或半对数线性关系。地震应力降、视应力与震源半径没有表现出明显的依赖关系,但与地震矩之间表现出正相关关系。与其他地区相比,此研究区属于低应力释放区域。更多还原

【Abstract】 Using the Brune model(1970) and the digital seismic wave data of Ningxia and the adjacent regions,which was recorded by Ningxia seismic network,we transferred the recorded velocity spectrum into hypocenter displacement spectrum by geometry diffusion correction,dielectric attenuation correction and instrumental correction.The corner frequency and zero frequency were calculated by using genetic algorithm,further,the hypocentral parameters including hypocentral radius and seismic moment were calculated and the relationships among them were analyzed systematically.186 earthquake events from ML1.7 to ML4.4 which occurred from June,2003 to December,2007 were studied.The estimated results show that the relations between seismic moment,body-wave magnitude,rupture radius and corner frequency are near log-linear or semi-log-linear.Seismic stress drop and apparent stress show little obvious correlation with hypocenter radius,but display positive correlation with seismic moment.Compared with other regions,there are lower stresses released in the studied region.更多还原