澜沧、耿马地震前的定点形变异常特征

FIXED-POINT DEFORMATION ANOMALY AND ITS CHARACTERISTICS BEFORE THE LANCANG-GENGMA EARTHQUAKE

摘要:

本文分析了1988年11月6日云南澜沧、耿马地震前定点形变异常特征。趋势性异常主要表现为异常持续时间较短,变化迅速,倾斜方向一致。异常持续过程中出现1-2个加速变化阶段;短期异常出现在震前2-6个月,主要表现为倾斜矢量打结、方向改变及速度明显减小;形变异常的方向与震中方向有一定的联系。

Abstract:

This paper analyses the characteristics of fixed-point deformation anomaly before the Lancang-Gengma,Yunnan Province,earthquake on Nov.6,1988.The results show that the trend anomalies are characterized by short,anomalous duration time,change rapid,consistent tilt direction in space,1-2 accelerated change stages during the anomalous duration process;the short-term anomalies appeared 2-6 months before the earthquake,with the tilt vector to knot,the direction change and the obvious velocity decrease;the direction of deformation anomaly has some contact with the epicentral direction.