关键词: 唐山地震, 卫星图象, 构造活动信息, 中期前兆

Abstract: The authors have comprehensively analysed 18 sets of 630 Landsat photos of different time phases and wave bands for North China. It is revealed that before the occurrence of 1976 Tangshan earthquake various indications of tectonic movement,including those of compresso-shearing and extension,appeared on Landsat images. These indications occurred 13-16 months before 1976 Tangshan earthquake,and thus can be considered as midrange precursors of earthquake. It is suggested that the monitoring of such indications of tectonic movement in Beijing-Tianjin area and other sensitive points by using Landsat data collected by satellite ground station,will be of great importance to the capture of midrange seismic precursors and thus to the seismic harzard reduction itself.

Key words: Tangshan earthquake, Landsat image, Midrange precursor, Indication of tectonic movement