Abstract：Thermal infrared anomaly before tectonic earthquake is a much studied topic related with seismology and remote sensing. In this paper, the thermal infrared anomaly before the Hengchun earthquake (Dec. 26, 2006, Ms=7.2) in Taiwan region is analyzed. The results show that the anomaly has the following features: ① a thermal infrared anomaly area appeared on the east of Philippines six days before Hengchun earthquake, and it gradually moved toward west; ② the anomaly moves to Philippines two days before shocking; ③ then the anomaly changed its moving direction from westward to northward, the anomaly became gradually close to the epicenter, and the strength as well as the scope of the anomaly region became more and more larger; ④ the strength of the anomaly reached the peak one day before shocking, and the brightness temperature increased by about 10℃. The relationship between the thermal anomaly and the tectonic activity of Taiwan region is also studied. The results indicate that the satellite thermal anomaly before Hengchun earthquake is evidently controlled by the tectonic activity of Taiwan region. It is suggested that the overall action of the out-going stress heating effect and the geothermal and the greenhouse effect initiated and amplified by the movement and concentration of crustal stress field in the seismogenic zone is the chief mechanism of satellite thermal anomaly before Hengchun earthquake.
2007, Vol. 25 
