Abstract: For the potential seismic sources of upper bound magnitude 7.5 or 8.0 in study area of Qilianshan, the occurrence intervals of magnitude 7.0～7.4 or 7.5～7.9 are calculated by using the method of slip rate, respectively. The intensity corresponding to 10% probability of exceedance in 50 years are calculated by using elliptical attenuation of earthquake intensity of western China and mixed model, which includes NB conditional probabilistic model and NB cumulative probabilistic model for characteristic earthquakes, and Segment-Poisson Process for medium earthquakes. The results show that the influence of the potential seismic sources with a long elapse time and a small area are stronger and the influence dilution should be considered for those potential seismic sources of large area.

Key words: Seismic regionalization, Characteristic earthquake, Seismic model, NB cumulative probabilistic model

摘要： 以祁连山为研究区,以上限震级7.5和8.0的潜源为特征地震段,利用滑动速率法分别计算上述每个潜源中7.0～7.4级,7.5～7.9级地震的复发间隔。特征地震选用NB模型条件概率和NB累积概率模型,中强震采用中国地震区划图(1990)的分档泊松模型,组成混合地震模型,用中国西部椭圆地震衰减公式,计算了未来50a,超越概率为10%的地震烈度。计算结果认为累积概率模型当地震离逝时间长而潜源面积小时影响大,面积大的潜源应进一步考虑潜源的稀释问题。

关键词: 地震区划, 特征地震, 地震模型, NB模型累积概率