云南彝良5.7级地震前卫星热红外异常  

Thermal Infrared Anomaly Prior to Yiliang of Yunnan MS5.7 Earthquake

作　　者：张璇[1] 张元生[1,2] 魏从信[1,2] 田秀丰[1] 冯红武[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1期171-176,共6页China Earthquake Engineering Journal

基　　金：国家科技支撑计划课题(2012BAK19B04);中国地震局兰州地震研究所青年基金(2011Q04)

摘　　要：针对2012年9月7日云南彝良5.7级地震前在震中区附近出现的大面积热红外异常,利用中国静止气象卫星FY-2C/E红外遥感亮温资料,采用功率谱相对变化法进行研究。结果表明:该次地震发生前一个月震源区附近存在明显的热异常区域,并且随着时间推移不断扩大、迁移;在2012年9月1日左右异常面积达到最大,随后逐渐收缩,相对变化幅度达10倍以上。同时发现该次亮温异常沿断层呈带状分布,应与活动构造分布有关。This study examines the thermal infrared anomaly occurring prior to the September 7,2012,MS5.7 earthquake in Yunnan Yiliang by analyzing infrared remote sensing brightness temperature data recorded by China Geostationary Meteorological satellite FY-2C/E.Infrared data of the prime time from 1：00 to 5：00 local Peking time was selected as the data source.Through data processing in which cloud data was disregarded,the power spectrum transform method was used to analyze and research the temporal evolution diagram of the earthquake thermal infrared anomalies and the timing curve of the brightness temperature average.The results show that 90 days prior to the earthquake,in approximately July 2012,a significant thermal anomaly area occurred near the epicenter,and exhibited irregular shapes.With the passage of time,the abnormal range gradually expanded along a particular direction of tectonic stress field,rapidly mutated,and gradually migrated from north to south.A large range of infrared anomaly up to hundreds of kilometers in length was recorded in the epicentral area,which is inconsistent with the temperature trend observed in the seismogenic zone.This abnormal area reached the maximum on September 1,2012,and gradually shrank after the earthquake occurred.The anomaly amplitude was rapidly reduced in the area near the seismogenic fault before disappearing.The earthquake thermal anomaly cycle was 64 days,and the thermal anomaly duration was more than 30 days.Prior to the earthquake,the magnitude of relative change was more than 10 times,for a maximum of the previous five years.From mid-July 2012 to the seismogenic day,the average increased sharply,and abnormal peaks appeared during the four days prior to the earthquake.After the earthquake occurrence,the characteristic amplitude gradually reduced,and anomalies dissipated step by step.Moreover,we determined that the brightness temperature anomaly exhibited zonal distribution along the fault,which should be related to the distribution of active tectonics.The thermal in

关 键 词：云南彝良5 7级地震 静止卫星 热红外遥感 亮温变化 相对功率谱 

分 类 号：P315.728[天文地球—地震学]