2017年8月8日九寨沟7.0级地震长波辐射异常特征

Anomaly of Outgoing Long-wave Radiation before the M7.0 Jiuzhaigou Earthquake on August 8,2017

通过距平方法,研究2017年8月8日九寨沟7.0级地震前震中所在区域(95.00°—110.00°E,25.00°—45.00°N)长波辐射时空演化特征,研究结果表明:①2017年7月,去除背景之后的长波辐射场在震区附近出现显著增强现象,增强区域基本走向与地质构造走向一致,其主体区域沿着巴颜喀拉块体南缘边界带,重要分支横跨巴颜喀拉块体,直接延伸至九寨沟7.0级地震震中;②紧邻九寨沟7.0级地震震中的4个格点在去除背景变化后的长波辐射时序曲线变化特征基本一致,即在2017年7月出现显著大于其他月份的现象。

This paper,using departure method,analyzes temporal-spatial characteristics of Outgoing Long-wave Radiation of the M7.0 Jiuzhaigou earthquake epicenter area(95.00°~110.00°E,25.00°N^45.00°N).The results show:firstly,there exist significantly enhanced abnormal areas of OLR field removing background value before the M7.0 Jiuzhaigou earthquake,whose strike is consistent with that of geologic structure;secondly,the four grid points adjacent to the epicenter of the M7.0 Jiuzhaigou earthquake have the same characteristics of the long-wave radiation time-series curve after removing the background changes,and their OLR values in July 2017 are significantly higher than ones in other months.