2012-04-11苏门答腊地震同震电离层异常研究

Ceseismic Ionospheric Anomaly of Sumatra Earthquake in April 11th, 2012

摘要: 2012041108:38:37UT和10:43:09UT苏门答腊地区先后发生了M8.6级和M8.2级强烈地震。本文采用震中附近地区9个IGS连续跟踪站的GPS观测数据,对两次地震的同震电离层异常现象进行了探测与分析。结果表明两次地震之后均出现了明显的同震电离层异常现象,异常出现的时间和异常的幅度与距震中的距离有关,异常的最大值约为2TECU,且震中偏北方向的异常最为显著。根据震中到穿刺点的距离,计算得出两次地震产生的大气声波的传播速度分别为0.73±0.06km/s和0.69±0.04km/s,与声波在0～450km内的平均传播速度一致。

Abstract: April11,201208:38:37UTand10:43:09UT,M8.6andM8.2earthquakesoccurredinSumatraarea.UsingGPSdata,nineIGScontinuoustrackingstationsneartheepicenter,thecoseis micionosphericdisturbanceaftertwoearthquakesweredetectedandanalysed.Theresultsshowedthatafterthesetwoearthquakes,significantcoseismicionosphericanomalieswereevident;theoccur rencetimeandamplitudeofanomalieswererelatedtothedistancefromtheepicenter;thatthemaxi mumanomalywasapproximately2TECU;andthemostsignificantanomalieswereinthenortherndi rection.Thecalculatedpropagationvelocityofsoundwavesgeneratedbythetwoearthquakeswere0.73±0.06km/sand0.69±0.04km/s;whichwasconsistentwiththeaveragepropagationofacous ticvelocitywithin0～450km.