摘要
通过对青藏高原东北缘重力观测资料进行系统分析,从动态的观点研究了2003年10月25日甘肃民乐 6.1及5.8级地震和11月13日甘肃岷县5.2级地震孕育发生过程中的重力场演化特征,得到如下结论:①从统一 起算基准获得的青藏高原东北缘重力观测资料,较完整地反映了2003年10月25日发生的民乐6.1级、5.8级地 震和11月13日发生的岷县5.2级地震孕育、发生过程中出现的流动重力前兆信息;②小波分解的重力场图像能较 清晰地反映地震孕育、发生过程中区域性重力趋势变化和震中地区深部物质密度变化引起的异常。
In this paper, the gravity observations in the northeastern margin of Qinghai-Tibet plateau area are analyzed, the evolution characteristics of gravity field in the seismogenic process of the Minle,earthquake on Oct. 25,2003 and the Minxian, earthquake on Nov. 13,2003 are studied from the dynamic viewpoint and the following conclusions are drawn: ①the gravity observation data of the northeastern margin of Qinghai-Tibet plateau obtained by use of uniform starting criteria can express the precursory gravity information during the seismogenic process of these earthquakes;②the dynamic patterns of gravity field through the multi-scale wavelet decomposition mirror clearly the tendentious local gravity variation and the anomalies caused by the material density variation in the depth of focal region during the seismogenic process of these earthquakes.
出处
《大地测量与地球动力学》
CSCD
北大核心
2005年第1期24-29,共6页
Journal of Geodesy and Geodynamics
基金
地震科学联合基金(105051)
中国地震局"十五"重点科研项目(100501 05 05)
关键词
地震孕育
重力场变化
8级地震
趋势变化
震中
演化特征
青藏高原
小波分解
图像
清晰
repeated gravity observation, gravity variation, earthquake, multi-scale wavelet decomposition, the northeastern margin of Qinghai-Tibet plateau
