地震失稳的滑动－弱化模式与大地震复发间隔估计

SLIP-WEAKENING MODEL OF EARTHQUAKES INSTABILITY AND RECURRENCE INTERVALS OF GREAT EARTHQUAKES

在考虑地震失稳的滑动－弱化特征后，研究了估计大地震重复间隔的问题，建议了一种计算大地震重复间隔的方法，给出了计算复发间隔的公式。同时，应用这个方法计算了海原断裂带、华山山前断裂带、贺兰山东麓断裂带和小江西支断裂带的８级大震复发间隔，它们分别为３４６６年、２０４３年、２６８８年和９７５年。这些数值与古地震研究给出的实际古地震复发间隔甚为一致，说明建议的计算方法可以应用于活动断裂地震复发时间和地震危险性的估计。

After taking the slip-weskening behaviour of earthquake instability into consideration,the recurrence intervals of great earthquakes have been estimated in the paper.A method for calculating large shock's recurrence intervals and its formula are put forward.Meanwhile,the recurrence intervals of large earthquakes with magnitude 8.0 happened in Haiyuan fault zone,Huashan piedmont fault zone,Helanshan eastern fault zone and western branches fault belt in Xiaojiang have been estimated as well,in detail,they are 3466 years,2043 years,2688years and 975 years respectively.When comparing them with the real recurrence intervals of paleoearthquakes,we found that they are quite coincidence,showing that the suggested calculating method can be used to estimate the recurrence interval of earthquakes in active fault zone as well as the seismic risk evaluation.