摘要
系统分析了河西地区 1992～ 2 0 0 1年流动重力测量资料 ,研究了重力场的时空动态演化特征。结果表明 :地震孕育发生阶段 ,重力场出现一定范围的区域性重力异常 ;震前震后重力变化所反映的构造活动含义不同 ;重力场变化与断裂活动密切相关 ,特别是跨断裂的重力变化能较好地反映断层活动特征 ;重力场变化与区域应力 应变场微动态活动及地震活动有关。
The mobile gravity data in Hexi area is systematically analyzed, and the dynamically evolutional characteristics in time and spatial domains of gravity field are researched.From the research results we have had following understandings.(1)In seismogenic stage, there is obviously regional gravity anomaly in a certain area of Hexi region, which is related to seismogenic process.(2)The different gravity variations before and after event reflect different tectonic activities. Before earthquake, it reflects the stress concentration in the seismogenic layer;after earthquake, it mirrors the movement of active fault in upper layer of crust.(3)The change of gravity field is closely relative to tectonic of active fault, which is coincident with the concentration zone of non-tidal change of gravity. It shows that the fault tectonic is active.(4)Small change of gravity corresponds obviously with seismisity, and it may be relative to micro-dynamic situation of stress-strain field.
出处
《大地测量与地球动力学》
CSCD
2003年第4期44-48,共5页
Journal of Geodesy and Geodynamics
基金
中国地震局"十五"重点科研项目"强震中期预测"
