用大地形变判定强震危险区的指标体系及河西地区垂直形变场演化

INDEX SYSTEM FOR DECIDING STRONG EARTHQUAKE RISK AREA BY GEODETIC DEFORMATION DATA AND EVOLUTION OF VERTICAL DEFORMATION FIELD IN HEXI REGION

提出了表征地壳垂直形变场定量特征的地壳垂直运动准加速度及体积变化率两个新指标，利用甘肃河西地区７０年代以来的５期复测水准资料计算了地壳剪切变形率、扩张变形率、体积变化率、速率增量、准加速度等各项指标，并分析了这些指标与强震危险区判定的关系．系统地研究了该地区垂直形变场的演化过程．

n this paper,two new indices,quasiacceleration of crustal vertical movement and crustal volume change rate,are presented,which will describe the characteristics of crustal vertical deformation field.The crustal shear deformation,extension deformation,quasiacceleration and volume change rate are calculated by using releveling data in Hexi area,Gansu since 1970s. The relation between these indices and earthquake risk region judgment is analyzed systematically.The procedure of crustal deformation field evolution in Hexi area is studied.