选取2010-2016年重庆地震台网记录的MS>3.0地震，对P波进行波谱分析，得到P波零频极限值、地震矩及拐角周期，拟合得到拐角周期与重庆地震台网MS的关系、P波零频极限值与重庆地震台网MS的关系，利用P波地震矩计算矩震级MWP，分析MWP与MS的差异。结果显示，当MS ≤ 4.0时，MWP > MS；当MS > 4.0时，MWP < MS，对得到的震级计算关系式检验发现，P波矩震级及通过零频极限计算得到的震级与重庆地震台网MS较为接近，而通过拐角周期计算得到的震级与MS相差较大。
Using the earthquakes with MS>3.0 recorded in Chongqing Seismic Network since 2010 to 2016, the amplitude and cycle information, namely the long-period spectral level and the moment and the corner cycle of P wave are gotten through spectrum analysis. The relation between the corner period of P wave and the MS, and the relation between the long-period spectral level of P wave and the MS are obtained. The MWP is calculated through the P wave moment. The difference between MWP and MS is analyzed. The results show that the MWP is larger than MS when MS ≤ 4.0, and the MWP is smaller than MS when MS>4.0. The results of hypothesis testing show that the MWP and the magnitude calculated from the long-period spectral level of P wave is relatively close while the magnitude calculated from the P wave corner cycle is in large difference.
2018,39(4): 12-17 收稿日期：2018-01-11
DOI：10.3969/j.issn.1003-3246.2018.04.002
基金项目：重庆市地震局科研项目"利用重庆台网P波记录计算震级"；重庆市地震局科研项目"用背景噪声和天然地震反演三峡库区岩石圈速度结构"
作者简介：陈丽娟(1988-),女,硕士研究生,四川邻水人,助理工程师,主要从事地震监测工作。E-mail:517133638@qq.com
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