热红外遥感以其大视野、高精度和短周期等诸多优势以及对某些强震红外异常的良好反映,成为监测断裂活动性及地震短临前兆的很有前途的观测技术。热红外异常与地震关系的研究也受到国内外地震学者的广泛关注。但由于地表热红外辐射受云层、地形地貌、地物类型和气象等诸多非震因素的影响,因此,如何从复杂的红外遥感数据中提取出与地震活动有关的热异常一直是这项研究中的瓶颈问题。在对若干震例和地震活动区的热红外影像进行长期分析研究的基础上。对这一问题进行了探讨,同时提出了一些实用化的异常识别与提取方法,并对其可行性进行了分析。认为地震红外异常是地表亮温的相对变化,判别地震异常时,至少需利用两年以上的卫星资料,从不同的时空尺度上加以综合对比分析,仅靠震前震后一定时段的卫星资料不足以排除所有非震因素的影响。
The satellite thermal infrared remote sense has become a promising technique for detecting earthquake and fault activities, because of its many advantages, such as large observation area, high spatial resolution and short observation period, also owing to its good reflection to some strong earthquakes'thermal anomaly. But the thermal infrared radiation of earth surface is influenced not only by earthquake and fault activities but also by many factors such as terrain, vegetation, weather and so on. Therefore, how to extract the thermal variation really related to earthquake and fault activities from complex infrared remote sensing data is a key problem. The paper, based on several year~ analyses of NOAA AVHRR data of typical tectonic active areas, gave a detail discussion to this question, put forward some applied methods for identifying and extracting thermal infrared anomaly caused by earthquakes or fault activities, and also evaluated the feasibility of these methods. The author thought the earthquake thermal infrared anomaly is a part of relative change of earth surface temperature. In order to effectively extract the earthquake anomaly and get rid of the impacts of non-earthquake factors, we need do comparative and comprehensive analyses using at least two years's satellite data in different temporal and spatial scale.