Abstract: Based on the data of 18 times of leveling carried out during 1954 to 1985, the relative stability degrees of relevelling nodes in the Tangshan area are calculated. According to these results, the characteristics of crustal vertical deformation before and after the Tangshan Earthquake(28/7/1976,M_s=7.8) are studied. Our study indicates that probably since 1968 significant relative movements between structural blocks in that area had appeared and continued till 1978. The seismic fault was in locked state before the quake. Finally, some viewpoints about the deformation monitoring and the evaluation of risk region of a strong earthquake are also presented in this paper.

Key words: Tangshan district, Stability, Relleveiing, Block, Deformation

摘要： 本文通过研究唐山地区各水准点的稳定性,探讨了唐山7.8级地震前后的地壳垂直运动特征。结果表明,大约从1968年开始,该地区各构造块体之间即存在明显的相对运动并持续到地震后2年。唐山地震断层在震前处于闭锁状态。本文还根据形变的演变过程对形变监测和危险区的判别提出了看法。

关键词: 唐山地区, 稳定性, 水准测量, 块体, 形变