1970年M_S 7.7云南通海大地震强地面运动模拟

Strong ground motion simulation of the 1970 M_S 7.7 Tonghai earthquake,Yunnan,China

对1970年云南通海大地震(MS7.7)进行了强地面运动模拟.采用复合震源模型和有限断层随机振动模型,针对包括昆明在内的4个特征城市的地表运动进行模拟计算.结果表明,在0.5～10 Hz频带范围内,2个模型的结果在波形、振幅、频率含量及持续时间上均具备较好的相似性.进一步采用复合震源模型模拟了通海地震的烈度分布图,与实际观测的烈度分布一致程度较高.

Using a composite source model, we simulate the strong ground motion from the 1970 Tonghai earthquake （Ms 7.7）. Due to the lack of strong ground motion recordings and for verifying the reliability of simulated results,a finite fault model, developed based on the stochastic theory with the same input source parameters including fault slip distribution pattern and size, is additionally used to generate synthetic strong motion seismograms for comparison purpose. The acceleration time histories at four selected sites or cities, simulated by the two models, show good agreements in the amplitude, waveform, frequency content, and time duration within the 0.5-10 Hz frequency domain.