四川地区震源参数和台站场地响应初步研究

Preliminary study on both earthquake source parameters and site responses of seismic stations in Sichuan Province

利用成都遥测数字地震台网数字地震波形数据资料,采用Atkinson方法得到四川地区的品质因子Q值与频率f的关系为:Q(f)=203.1f0.834。采用Moya方法反演得到了地震的场地响应,采用Moya方法与Atkinson方法分别得到了相应地震的震源谱参数,两种方法的结果保持了很好的一致性。得到的震源参数结果表明:地震矩与震级的关系为:logM0=17.27+1.18ML,地震矩与拐角频率关系,即随着地震矩的增大,拐角频率减小,这些地震的应力降在10～400巴之间,应力降与地震矩之间没有明显的依赖关系。

By using the seismic wave data from the Digitalized Remote Seismic Station Network of Chengdu, the relationship between the quality factor Q value and frequency for Sichuan province with the method of Atkinson, Q （f） = 203. 1f0.834, is got. Then we use the Moya inversion method to calculate the site responses of a seismic station. The comparison of the earthquake source spectral parameters respectively from both method of Moya and Atkinson are made. The earthquake sources parameters from both methods of Moya and Atkinson are consistent with each other. Our calculated parameters show that the relationship between seismic moment and seismic magnitude is logM0 = 17.27 ＋ 1.18 ML. The comer frequency decreases with the increasing of seismic moments and the stress drop is from 10 to 400 Pa. The stress drop do not show clearly connected with the seismic moment.