河西——祁连山重复重力测量资料的地震前兆信息研究

利用傅立叶分析法分离出河西－祁连山地区重力变化的长波项和短波项，进而推导出重力场所产生的散度散计算公式，分别计算出各时段的重力散度值，绘制出重力变化的长波项和短波项及散度等值线图，并结合该地区的地震活动和地壳深部构造资料进行综合分析研究，初步得出以下认识：（１）重力非潮汐变化的长波项是由地壳深部物质迁移所引起，具有ＮＷ向特征，与区域构造运动的继承性有关。通常把它作为地壳运动的正常值；（２）重力非潮

EARTHQUAKE PRECURSORY INFORMATION EXTRACTED FROM GRAVITATIONAL DEFORMATION IN HEXI-QILIAN AREA

In this paper, the Fourier-analysis method is used to separate the longwave andshortwave information of gravitational deformation of Hexi-Qilian area. The studyreaches the following conclusionst 1. The longwaves show that the movement of materialunder the earth's crust is the background of earthquake activity; but the shortwaves are re-lated to earthquake precursors, 2. The trait of both the longwave and the shortwave havehigh grade area, but their physical meaning is different; The high grade area of thelongwave is caused by the different structures of earth's crust; The high grade area of theshortwave is the earthquake risk region; 3. The source of the vertical force of Hexi-Qiliarnarea is in some blocks and a short time that results from the movement of the material un-der the crust that is in some blocks and in a short time.