摘要
从地震矩张量的理论和点源的垂直位移公式出发,通过离散化地震矩密度,得到了用水准资料反演断层非均匀破裂的有限元模型。利用唐山地震前后的水准资料,采用非负限制的梯度方法反演了唐山地震的非均匀破裂,发现唐山地震的破裂主要是由两部分组成的,其中最大点滑动量为9.90m。计算得到地震矩为1.5×10(22)N·cm,说明唐山地震前后一年内的垂直形变是同震变化。
On the basis of the seismological moment tensor theory and the vertical displacement formula of point source, by means of diseretizing the moment density, the finite element model to inverse fault non-uniform rupture from levelling data is obtained. We calculate the vertical displacements caused by uniform and non-uniform rupture of dip-slip fault and strike-slip fault. The feasibility data is investigated in detail with the aid of numerical simulation. Sequently the non-uniform rupture of the Tangshan earthquake is inversely gotten from levelling data before and after the earthquake in the nonnegative restriction gradient method. The result shows that the Tangshan earthquake is mainly made up of two parts, the maximal values of points slip coming to 9.90 meters. The seismic moment calculated is 1. 5×10(22) N·cm. It indicates that the vertical deformation within one year before and after earthquake is coseismic variations.
出处
《地壳形变与地震》
CSCD
1995年第2期7-14,共8页
Crustal Deformation and Earthquake
关键词
地震矩
水准测量
唐山地震
错动模型
地震
Seismic moment, levelling, inversion, Tangshan earthquake, non-uniform rupture.