1986年门源地震(MS 6.4)过程地形变演化特征及块体模型解析

DEFORMATION FEATURES OF MENYUAN EARTHQUAKE (MS 6.4, 1986) AND BLOCK MODEL ANALYSIS

摘要:

分析了1986年门源6.4级地震震源周边地区不同尺度跨断层形变在地震过程中的演化特征,依据非连续变形数值分析方法(DDA)模拟了震源破裂过程引起的地表垂直位移速率变化.分析表明,地表跨越断层的剖面形变变化是垂直和水平载荷共同作用的结果,而垂直力源的影响可能是引起本次地震形变变化的主要因素.这与地质构造分析和震源机制结果是吻合的.

Abstract:

The evolution features of cross-fault deformation in different scares during seismogenic process near epicenter of Menyuan earthquake (M_S 6.4, August 26, 1986)is analyzed. Based on theory of Discontinues Deformation Analysis (DDA)the Displacement Loading Method is applied to simulate vertical displacement velocity change due to focal rupture. The result shows that combination of vertical and lateral force produce the deformation change on earth surface, and the former may be more important.