摘要
应用卫星遥感数据,采用相对功率谱法和均线差值振幅增强比法,提取甘肃积石山6.2级地震前的热红外信息。结果表明,震前存在显著的热红外异常现象。相对功率谱法提取到的热红外异常现象分为两个阶段:(1)在2023年10月以托莱山断裂和冷龙岭断裂交汇处为核心区,出现了沿北东向展布的热红外异常(功率谱最高值超过8);(2)在2023年11月,冷龙岭断裂和金强河断裂交汇处至日月山断裂和拉脊山断裂交汇处出现了较弱的热红外异常(功率谱最高值不到7),异常的空间演化逐步向震中靠近。均线差值振幅增强比法的计算结果显示出背景性异常的特征,9月在祁连山中东至甘东南段出现了显著的长波辐射异常,两种热红外异常提取方法的结果起到了互相佐证的作用。
Based on the satellite remote sensing data,the thermal infrared information before the Jishishan M_(S)6.2 earthquake in Gansu Province was extracted using the relative power spectrum and mean-line difference amplitude enhancement-ratio methods.Results show the presence of considerable thermal infrared anomalies before the earthquake.Two stages of thermal infrared anomalies extracted from the relative power spectrum are available:(1)in October 2023,the NE-trending thermal infrared anomaly was concentrated in the intersection of Tuolaishan and Lenglongling faults(the maximum value of power spectrum is more than 8).(2)In November 2023,a weak thermal infrared anomaly(the maximum power spectrum value is less than 7)emerged from the intersection of the Lenglongling and Jinqianghe faults to the intersection of the Riyueshan and Lajishan faults.The thermal infrared anomalies gradually approached the epicenter.The calculation results of the mean-line difference amplitude enhancement-ratio method show the characteristics of background anomalies:in September,the anomaly of outgoing longwave radiation occurred from the eastern section of the Qilian Mountains to the southeast of Gansu Province.The two methods for extracting thermal infrared anomalies serve as complementary pieces of evidence.
作者
钟美娇
张元生
廖洪月
郭晓
ZHONG Meijiao;ZHANG Yuansheng;LIAO Hongyue;GUO Xiao(Gansu Lanzhou Geophysics National Observation and Research Station,Lanzhou 730000,Gansu,China;Xi'an Earthquake Agency,Xi'an 710021,Shaanxi,China)
出处
《地震工程学报》
CSCD
北大核心
2024年第4期880-887,共8页
China Earthquake Engineering Journal
基金
中国地震局地震预测研究所基本科研业务专项(2022IESLZ01-05)
甘肃省自然科学基金(23JRRA1566)。
关键词
热红外遥感
亮度温度
长波辐射
地震
thermal infrared remote sensing
brightness temperature
outgoing longwave radiation
earthquake
