【摘要】 云南地区 2 0 0 1年 4月 10日至 6月 8日相继发生了 4月 10日MS5 .2、4月 12日MS5 .9和6月 8日MS5 .3的施甸地震 .本文利用云南遥测数字地震台网的保山地震台记录的地震波形资料 ,使用SAM分析方法 (即剪切波分裂系统分析方法 ) ,采用地震应力预测的分析手段 ,对这个强震系列进行剪切波分裂参数变化特征的研究 .初步结果表明 ,随着地震活动的增强 ,剪切波分裂时间延迟值Δt基本呈现增加的特征 ,但在强震即将发生之前的短时间内 ,发生Δt减小的现象 ,符合我们早先研究发现的震前应力释放现象 .研究认为 ,在地震活动强烈的构造地区和有强震发生危险的经济发达地区或重要城市 ,开展强烈地震的应力预测应用实践 ,可以减轻地震的危害程度 .更多还原

【Abstract】 In 2001 three earthquakes occurred in Shidian in Yunnan Province, which were the M S=5.2 on April 10, the M S=5.9 on April 12 and the M S=5.3 on June 8. Based on the data from the station Baoshan of Yunnan Telemetry Digital Seismograph Network, the variational characteristics of shear-wave splitting on these series of strong earthquakes has been studied by using the systematic analysis method (SAM) of shear-wave splitting. The result shows the time delays of shear-wave splitting basically increase with earthquake activity intensifying. However the time delays abruptly decrease immediately before strong aftershocks. It accords with the stress relaxation before earthquakes, which was found recently in study on shear-wave splitting. The result suggests it is significant for reducing the harm degree of earthquakes to develop the stress-forecasting on earthquake in strong active tectonic zones and economic developed regions or big cities under the danger of strong earthquakes.更多还原