Abstract: We have studied the magnitude,epicentre of recent earthquakes,and spacial distribution of ground seismic ruptures on the Ganzi-Yushu fault. We have estimated the tendency of major earthquakes for each segment of the Ganzi-Yushu fault zone in the future 50 years by using the probability model of the general distribution for repeat time of characteristic earthquakes (Nishenko and Buland,1987). Our results show that the Manigange segment has high risk of recurrence of large earthquakes in the future 50 years. The possibility of major event recurrence on the Dangjiang segment also exists. These estimates can provide a basis for the long-and mid-term earthquake prediction for this region.

Key words: Coseismic dislocation, Earthquake recurrence interval, Seismicity trend

摘要： 通过对甘孜-玉树断裂带上近代地震的震级、震中位置和地震地表破裂的空间展布特征的研究,采用Nishenko和Buland(1987)发展的“特征地震复发时间通用分布”概率模型,即“NB”模型,对甘孜-玉树断裂带各段落未来50a内强震趋势进行了估计。根据研究结果识别出,未来50a内本断裂带内马尼干戈断裂段具有强震复发的高危险性,当江断裂段强震复发的可能性也不能排除,这为地震中长期预报提供了重要依据。

关键词: 同震位错, 地震复发间隔, 地震活动趋势