【摘要】 本文研究用理论地震图反演地震震源参数的方法,利用16个WWSSN台记录的渤海地震（1969年7月18日,M=7.4）远震P波波形,用我们的反演方法重新测定了该地震的震源参数。文中以剪切位错源的理论地震图与实际观测记录波形的相关程度为判据,测得该地震的震源参数为:地震矩3.9×10²⁷达因·厘米;震源破裂持续时间6秒;位错面两个可能的选择解是:（1）θ_s=207°,δ=87°NW,λ=-159°,右旋;（2）θ_s=298.6°,δ=69°NE,λ=-3.6°,左旋。其中θ_S、δ、λ分别是震源位错面的方位角、倾角和错滑角;震源深度为25公里。数值运算的结果还表明,本文提供的测定震源参数的方法实际效能良好。 文中还与用P波初动符号方法测定的震源参数结果进行了对比分析。更多还原

【Abstract】 This paper gives a method which inverses the parameters of a shock focus by means of computing a synthetical seismograms. The focal parameters of Bohai sea (on July 18, 1969, M=7.4) are determined again with our method according to the teleseismic P wave recorded by 16 WWSSN stations. Based on a correlation criterion between the shapes of synthetical seismogram for a shear dislocated source and the actually observed seismograms we determined the focal parameters of this earthquake as follows: the seismic moment is 3.9×1027 dyne-cm; duration time of source rupture is 6 seconds; two possible choice solutions for a dislocated surface are (1) θs = 207°, δ = 87°NW, λ = -159°, right-lateral and (2) θs = 298.6°, δ=69° NE, λ=-3.6°, left-lateral (where θ., δ, λ express strike angle, dip angle and rake angle respectively); epicenter depth is 25 kilometers. Those results are compared with the focal parameters determined by first motions of P wave. The results of numerical calculations show that our method gives concordant results.更多还原