华北地区强震前地壳垂直形变和重力异常  

RESEMBLANT CHARACTER OF VERTICAL CRUSTAL DEFORMATION AND GRAVITY ANOMALIES BEFORE MACROSEISM IN NORTH CHINA

作　　者：刘善华[1] 尹荣珍[1] 李民[1] 陈白鹭[1] 

机构地区：[1]中国地震局综合观测中心,北京100039

出　　处：《大地测量与地球动力学》2002年第3期34-39,共6页Journal of Geodesy and Geodynamics

摘　　要：分析总结了唐山、大同和张北 3次强震前地壳垂直形变异常和重力异常的相似特征 ,即震前均表现为地壳垂直形变正异常和重力正异常。大陆动力学的解释是由于深部上地幔的隆起造成的 ,大同地震与唐山地震、张北地震具有相似的孕震机理。华北强震的孕育与发生可能都与地幔热物质上涌有关 ,这可能是板内地震最主要的成因。要特别注意地幔隆起区内的高导层与深大断裂的交叉部位 。The resemblant character of the vertical crustal deformation and gravity anomaly before three macroseism in Tangshan, Datong and Zhangbei are studied and summarized.Both the vertical crustal deformation and gravity show positive anomaly before earthquake.According to continental dynamics the rise of upper mantle leads to this result.The mechanism of Datong earthquake is similar to these of the earthquakes occurring in Tangshan and in Zhangbei.It is possible that the development and occurrence of macroseism in North China are all related to the rise of hot mantle material,and this is the main genesis of intraplate earthquake.The close attention should be paid to the crossing position of the high-conducting Iayer with the big deep fault in upward mantle area.The Yanhuai area may be a danger area of strong quake developing in the future. The above analysis is significant for forecasting the coming macroseism, especially in the area, on whose surface there is no obvious fault.

关 键 词：华北地区 地壳垂直形变异常 重力异常 大陆动力学 地幔隆起 

分 类 号：P227[天文地球—大地测量学与测量工程]