【摘要】 谱震级是表征地震强弱的量度,是地震学研究中的一个重要的地震参数。在地震预测和工程地震研究中具有重要的实际意义。谱震级测定还可得到地震辐射的能量,再通过和标量地震矩的比较,可以估计地震震源处的视应力,而视应力也是震源物理研究中一个重要的物理量。考虑到我国地震台网分布不均匀的情况,本文尝试利用单台的宽频带波形资料进行谱震级的测定。选用CDSN昆明地震台(KMI)记录的近震宽频带波形资料,分析地震图垂直分量上的P波,采用 Duda等人提出的谱震级的测定方法,改进并提出了一种能够利用宽频带波形资料,直接用速度谱值测定地震谱震级的方法。所得谱震级结果与ISC给出的Ms震级对比后,发现相差不大;所得的能量结果与NEIC用远震体波测得的能量结果具有较好的一致性。用同样的方法,将来还可对不同地区更小的地震进行谱震级的测定,这无疑对地震学的进一步研究很有帮助。更多还原

【Abstract】 Spectrum magnitude of an earthquake is an important source parameter of earthquake size in seismology research. Spectrum magnitude is often related to the seismic prediction that is crucial in the study of seismic engineering. Measurement of spectrum magnitude of earthquakes may give the estimate of radiated energy of an earthquake. Besides, measurement of radiated energy, together with the measurement of seismic moment, may give the estimate of apparent stress that is shown to be useful in the physics of seismic source. Due to the sparse distribution of seismological stations, analysis of seismograms at a single station for the measurement of Spectrum magnitude plays an important role for regions in developing countries such as China. In this study, we take the CDSN Kunming station (KMI) in Yunnan Province as an example, focusing on the earthquake recorded by this station at local to regional distances, within 10?around the station. Broadband (BB or IP) seismograms of the transverse component are used. The main ingredients of seismic phases considered are basically the P waves, taking the method of Duda etc. a calculation algorithm for fast estimating the broadband Spectrum magnitude of earthquakes based on single station data is developed in the dissertation. Comparison with the radiated energy published by the National Earthquake Information Center (NEIC), it shows that the two results fit well. The results also show a clear linear relation with the MS publicized by ISC, which further verifies the reliability of the method. Using similarly method, Spectrum magnitude is often related to the small earthquakes which is very helpful in the seismology research.更多还原