汶川MS8.0地震前卫星红外异常研究OA

Based on over 20 years of MODIS satellite remote sensing infrared data,we extract bright-ness temperature low-frequency information using anomaly method and spatial anomaly superposition method,and investigate the temporal and spatial evolution and characteristics of infrared radiation a-nomalies before the WenchuanMS8.0earthquake on May 12,2008.The results show that there was a significant radiation enhancement anomaly before the earthquake.In terms of time,from 2006 to 2007,there was a trend of radiation enhancement in the core area located west of the epicenter.Con-versely,from 2008 until the earthquake occurrence,this radiation enhancement exhibited a weakening trend.Spatially,the core area of radiation enhancement is located in the eastern section of Bayan Har and Qiangtang blocks,encompassing approximately 5.8 × 105 km2.The spatial distribution character-istics are consistent with the dynamic background of Wenchuan earthquake.