卫星热红外异常——四川汶川Ms8.0级大地震的短临震兆

Satellite Thermal Infrared Anomaly:a Short-term and Impending Earthquake Precursor before the Wenchuan Ms8.0 Earthquake in Sichuan,China

利用我国FY-2C红外一波段（10．3～11．3μm）的卫星遥感图像，通过解译和研究，发现在5．12汶川大地震之前，就出现了明显、孤立的卫星热红外异常现象。其异常现象的特征具体表现为：①震兆出现早：即在2008年3月18日（震前55d），就开始出现了热红外异常；②异常阶段多且复杂：汶川地震前的卫星热红外异常，可分5个阶段，而且热红外异常的展演各有不同。这在众多的卫星热红外地震研究案例中，可能是迄今为止异常阶段最多的一次；③单个阶段的持续时间长：最长达13d；④如此沿龙门山地震断裂带分布的明显的地热增温异常现象，可能在卫星热红外地震研究案例中是首次发现。这对研究发震特点、余震走向具有重要指示和启示意义。本项研究的结果再一次证明：作为地震短临震兆，在地震（特别是≥Ms5．0）前必然出现热红外异常现象的实践性和规律性。利用卫星热红外异常现象进行地震短临预测研究是最有效和最有可能突破地震预测科学问题的途径和方法之一。

Based on an interpretation and study of the satellite remote-sensing images of FY-2C thermal infrared 1^st wave band （ 10.3 - 11.3μm） designed in China, the authors found that there existed obvious and isolated satellite thermal infrared anomalies before the 5, 12 Wenchuan Ms8.0 Earthquake. These anomalies had the following characteristics： ①The precursor appeared rather early： on March 18, 2008, i.e., 55 days before the earthquake, thermal infrared anomalies began to occur; ②The anomalies experienced quite a few complex evolutionary stages： the satellite thermal infrared anomalies might be divided into five stages, whose manifestations were somewhat different from each other. The existence of so many anomaly stages is probably observed for the first time in numerous cases of satellite thermal infrared researches on earthquakes; ③Each stage lasted quite a long time, with the longest one spanning 13 days; ④An evident geothermal anomaly gradient was distributed along the Longmen Shan seismic fracture zone, and such a phenomenon might also be discovered for the first time in satellite thermal infrared earthquake researches. This discovery is therefore of great guiding and instructive significance in the study of the earthquake occurrence itself and the trend of the post-earthquake phenomena. The results of the authors＇ studies have proved once again the correctness of the regularity that, as a short-term and impending earthquake precursor, thermal infrared anomalies would surely appear before an earthquake （espeially the earthquake with magnitudes ≥ Ms 5.0）. The application of satellite thermal infrared anomaly phenomena to the short-term and impending earthquake prediction and research seems to be one of the most effective methods for a breakthrough in earthquake prediction.