震前卫星红外亮温异常时空演化特征分析

Spatio-temporal Evolution Characteristics of Satellite Infrared Brightness Temperature Anomalies before Earthquakes

摘要:

主要利用统计方法建立红外亮温背景场及异常检测模型，来提取2012年华北地区的红外亮温异常信息，并对2012年唐山4.8级地震和宝坻4.0级地震前的异常演化过程进行分析研究。结果表明：背景场方面，红外亮温的多年月背景场具有夏高冬低的年变特征，符合季节变化规律，红外亮温与高程呈负相关关系；基于历年同期亮温偏移指数K值方面，2012年5月28日唐山4.8级地震震前在唐山断裂带以南存在明显强烈的K值异常，在震前8小时达到最大约3.3。6月18日宝坻4.0级地震在震前也存在红外亮温异常现象，但是较弱。

Abstract:

In this paper, the infrared brightness temperature background field and the anomaly detection model were established by the statistical method to extract the infrared brightness temperature anomalies in North China, and the evolution process of anomalies before the Tangshan M4.8 and Baodi M4.0 earthquakes in 2012 were analyzed. The results indicated that:(1) The monthly background field of infrared brightness temperature has the annual variation characteristics of being higher in summer and lower in winter, which is in line with the seasonal variation law, and the infrared brightness temperature has a negative correlation with the elevation; (2) Based on the K-value data of brightness temperature over the same period in previous years, it was found that strong K-value anomalies were shown in the south of Tangshan fault zone before the Tangshan M4.8 earthquake on May 28, 2012, and 8 hours before the earthquake, the maximum value reached 3.3. Before the Baodi M4.0 earthquake on June 18, a weak anomaly of infrared brightness temperature also existed.