卫星热红外异常与地震关系的研究是目前地震领域的前沿课题,而从复杂的热红外信息中提取真正由地震活动引起的红外异常则是这项研究的关键和难点所在.本文以2004年3月24日在内蒙东部发生的5.9级地震为例,对热红外异常与地震的关系及异常提取中的相关问题进行了探讨.首先对震前3个月的NOAA16卫星影像进行了分析,结果发现震前三个月研究区出现了明显的热红外增温异常.异常影象特征表现为表面光滑、亮度均匀、边界清晰的高温雾状物;异常出现的空间位置不固定,面积大小不固定,异常无明显移动方向,亮温高出周围区域约3-10K.之后,叉对研究区两年的NOAA卫星影象进行了连续分析,结果发现了同样的异常现象.对比分析两年内异常的时空演化过程进一步认识到,此异常具有明显的季节性,在冬春季节重复出现.2004年3月24日的5.9级地震刚好发生于异常的多发期末,从震前震后短期内的卫星资料看,易将其判为震兆红外异常.最后结合研究区的地理环境和气象等因素,对异常的成因进行了探讨,认为它可能是由大气逆温引起的红外现象,并非地震前兆异常.
subject of The study on the relation between satellite thermal infrared anomalies and earthquakes is a new seismology in recent years, and yet, how to extract the infrared anomaly really related to which occurred on Mar 24 2004 in eastern Inner Mongolia, anomalies and earthquakes, and explores some problems earthquake This paper, exampled by the Ms5.9 earthquake discusses the connection between thermal infrared on earthquake anomaly extraction. Firstly, the NOAA16 satellite images three months before the earthquake are interpreted and analyzed. As a result, evident thermal infrared anomalies are found, which have following characteristics. The anomalies look like fog in images with even brightness, smooth surfaces and clear bounds, but their temperatures are higher than that of the ground. The locations of the anomalies are changeable, and the areas of the anomalies are variable in size, looking as if the anomalies float above the ground without direction of moving and extending. The magnitude of the anomalies can reach 3 - 10K. Secondly, the NOAA16 satellite images of two years are analyzed, and similar infrared anomalies are found again. An analysis of temporal and spatial evolution processes of the anomalies shows that the anomalies appear in the winter seasonally. It is possible to take the anomalies as earthquake precursor by mistake only depending on those satellite data several days or months before a shock,Finally, the causes of formation for the anomalies are probed, and the conclusion is that they are probably pruduced by atmosphere temperature inversion phenomena, not by the earthquake.