澜沧江流域小湾、糯扎渡水库地震台网震级完备性初探

Preliminary Study on Completeness of Magnitude for the Xiaowan and Nuozhadu Reservoir Seismic Networks in Lancang River Basin

利用b值稳定性方法计算了云南省澜沧江流域上的小湾和糯扎渡水库台网地震目录的最小完整性震级MC,并对其实际监控能力进行了分析。结果表明,随着台网的建设,小湾水库台网的监控能力呈微弱下降,MC由一期台站运行时的ML1.6变为一、二期台站运行时的ML1.7,表明台网的运行情况影响了其监控能力;糯扎渡水库台网的监控能力有了显著的提高,MC由一期台站运行阶段的ML1.3变为一、二期台站合并运行后的ML0.8。

The minimum magnitude of completeness Mc of the seismic catalog for Xiaowan and Nuozhadu Reservoir Seismic Networks in Lancang River Basin is calculated by b-value stability methods and the actual monitoring ability of the two reservoirs is analyzed.The results show that the monitoring capability of the Xiaowan Reservoir Seismic Network had been decreased weakly along with the construction of the networks.The Mc increased from ML 1.6 in the first stage operation to ML1.7 after the merge operation of the first and second stages,which indicated that the operation of the seismic network influenced its monitoring capability.The monitoring capability of the Nuozhadu Reservoir Seismic Network improved significantly.The Mc reduced from ML1.3 in the first stage operation to ML0.8 after the merge operation of the first and second stages.