2018年5月28日松原MS5.7地震热红外亮温异常分析

基于2016年5月29日—2018年5月28日中国静止气象卫星FY-2E （FY-2G）的连续亮温观测数据，利用连续小波变换法分析了2018年5月28日松原M_S5.7地震前震中附近（119°E—134°E，40°N—50°N）热红外亮温相对小波能谱的时空演化。结果显示:自2018年2月起，热红外亮温相对小波能谱首先在北西向的第二松花江断裂前郭部分出现高值异常；随后异常范围沿第二松花江断裂前郭部分和扶余—肇东断裂扩展，至2018年3月异常范围及幅值达到峰值；而后异常空间分布逐渐向震中附近收缩成一条NE走向的沿扶余—肇东断裂分布的窄带状区域，异常幅值逐渐降低；最终于４月中旬异常在该区域内消失，其后约40天发生松原M_S5.7地震，震中位于异常区域的边缘。此外，本文还分析了2013年以来研究区域内热红外亮温相对小波能谱高值异常与所发生地震的对应关系，结果显示:在7组异常中有4组异常出现后有地震发生，且此4次地震为该时段内研究区内所发生的所有浅源地震。 

Thermal infared brightness temperature anomaly evolution associated with Songyuan MS5.7 earthquake on May 28, 2018

This paper analyzes relative wavelet power spectrum （RWPS） of thermal infrared brightness temperature in the vicinity of the epicenter of the Songyuan M_S5.7 earthquake on May 28, 2018 （40°N—50°N, 119°E—134°E） by using continuous wavelet transform method based on daily brightness temperature data from Chinese geostationary meteorological satellite FY-2E （FY-2G） during the period from 28 May 2016 to 2 May 2018. The characteristics of spatio-temporal evolution results showed that the thermal infrared bright temperature relative wavelet energy spectrum reached high value along the Second Songhuajiang fault with the NW direction since February of 2018, then anomalous areas gradually enlarged and gathered along the Qianguo segment of the Second Songhuajiang fault and Fuyu-Zhaodong fault. The anomaly amplitude reached maximum in March and attenuated quickly, and then shrinked into a narrow band along Fuyu-Zhaodong fault near the epicenter with anomaly amplitude decreasing gradually and disappeared till 40 days before the Songyuan M_S5.7 earthquake. The epicenter is on the edge of the anomaly area. Furthermore, we analyzed thermal infrared brightness anomalies and corresponding earthquakes in the studied area since 2013, and the statistical result showed that four of the seven groups of anomalies correspond to earthquakes which were all the shallow earthquakes occurred in the area during that period.