四川芦山7.0级地震卫星热红外异常解析  

Analysis of Thermal Infrared Anomaly before the Lushan M_S7.0 Earthquake

作　　者：张璇[1] 张元生[1,2] 魏从信[1,2] 田秀丰[1] 汤倩[1] 高见[1] 

机构地区：[1]中国地震局兰州地震研究所,甘肃兰州730000 [2]中国地震局地震预测研究所兰州创新基地,甘肃兰州730000

出　　处：《地震工程学报》2013年第2期272-277,共6页China Earthquake Engineering Journal

基　　金：中国地震局兰州地震研究所青年基金(2011Q04);国家科技支撑计划课题(2012BAK19B04);兰州地球物理国家野外科学观测研究站开放基金(2013Y04)

摘　　要：以中国静止气象卫星FY-2C/E亮温资料为数据源,采用功率谱相对变化法对2013年4月20日四川芦山7.0级地震进行震例数据处理和分析。结果显示:震前热异常具有明显时空特征,2013年3月底震中及其北部区域出现热红外异常,异常区范围随时间逐渐扩大、幅度陡增;4月13日左右异常面积达到最大,随后缓慢收缩,异常持续时间近一个月,异常幅度最大值达到9倍多,最大值后3天发震。该次地震热红外异常特征显著,易于识别,进一步验证了卫星热红外异常在地震预判方面的作用。Aiming at analyzing the thermal infrared anomaly that occurred before the MS7.0 earthquake in Lushan,Sichuan,remotely sensed infrared brightness temperature data from China Geostationary Meteorological satellite FY-2C/E was collected,and the infrared data from the prime period from 1：00 to 5：00 Peking time was selected as the data source.By processing the data to eliminate cloud cover and by using the power spectrum transform method,we analyzed the thermal infrared anomalies in the earthquake temporal evolution diagram and the timing curve of the average brightness temperature.The results showed that a month before the earthquake,a small area of thermal anomaly existed just north of the epicenter,and this area showed irregular shapes.With the passage of time,the abnormal range gradually expanded along a certain direction in the tectonic stress field.From April 4,the abnormal area expanded along the northeasterly direction and reached its maximum on April 13,2013.At the same time,a small-scale anomaly was discovered just south of the epicenter,with the epicenter always being at the edge of the abnormal parts.The earthquake cycle related to these thermal anomalies was 64 days,and the thermal anomalies lasted more than 30 days.Before the earthquake,the magnitude of the relative change was greater than 9 times,the greatest in the past two years.From the end of March to the seismogenic day,the average increased sharply,with the abnormalities peaking 3 days before the earthquake,which is similar to the Wenchuan earthquake of May 12,2008.We simultaneously found that the brightness temperature anomaly was distributed consistently along the fault,which should be related to the distribution of active tectonics.The thermal infrared anomalies before the earthquake were fairly obvious and persistent over time,and went through two stages,initial warming and strengthening warming.The abnormal area moved and expanded rapidly along the fault direction.The epicenter of this earthquake was not in the area of maximum abnormality

关 键 词：四川芦山7 0级地震 静止卫星 热红外遥感 相对功率谱 亮温变化 

分 类 号：P315.75[天文地球—地震学]