[关键词]
[摘要]
基于MODIS卫星遥感红外数据,用小波方法提取并分析了汶川和芦山地震前后巴颜喀拉地块中东段红外亮温低频信息。结果显示,①在汶川8级地震前,巴颜喀拉地块中东段红外亮温升温异常多次出现(5 次),震后近5年无升温异常出现,在芦山7级地震前2个月再次出现升温异常;②汶川地震前升温异常的高值区在空间上有逐渐往龙门山断裂带方向迁移的特点;③在全部6 次升温异常中,只有2008年4~6月和2013年2月~4月19日2次临近地震的异常,巴颜喀拉地块中东段内部亮温出现大幅度均衡升温,这可能是该地区强震的临震信号。
[Key word]
[Abstract]
In this paper,the low frequency of infrared brightness temperature of central-eastern Bayan Har block before and after the Wenchuan and Lushan earthquakes is extracted and analyzed by the wavelet method based on the remote sensoring infrared data from MODIS /TERRA. The results show that: (1) 5 sharply infrared brightness temperature increasing anomalies occurred 2 years ago before the Wenchuan MS8. 0 earthquake,while there was none of the same anomaly after the quake in 5 years until a new one appeared 2 months before the Lushan MS7. 0 earthquake. (2) In spatial,the high value abnormal region migrated towards Longmenshan fault zone gradually over time. (3) Only 2 of all the 6 anomalies are impending ones,which are from April to June,2008,and from February to April 19,2013,respectively. The sharply temperature increasing phenomenon in the central-eastern Bayan Har block may be the strong earthquake indicator of this region.
[中图分类号]
[基金项目]
四川省地震局地震科技专项( LY1311)资助