【摘要】 以所建立的川滇地区主要活动块体及其周边断裂带的模型和前期利用GPS及水准资料反演所得到的断裂带长期运动速率作为基础,将汶川地震引起的同震错动量加入到三维断裂几何模型中,计算出汶川地震大范围的同震形变场,然后基于该同震形变场和活动断裂三维几何模型反演了各条断裂对该同震形变场的反映,并通过与各断裂带长期运动速率对比,得到了汶川地震对川滇地区各主要活动断裂带发震趋势的影响.结果表明,在汶川地震引起的同震形变场作用下,在川滇交界东部地区,龙门山断裂带南西段地震危险性提前了305a,鲜水河断裂带南东段大致提前了19a,安宁河断裂带和则木河断裂带分别提前了21a和12a,大凉山断裂带北段和南段分别提前了9.1a和18a,马边断裂带的地震危险性则提前了51a;对川滇交界西部的丽江—小金河断裂带南西段、怒江断裂带、龙陵—澜沧断裂带、南汀河断裂带、中甸断裂带等断裂带地震的能量积累也有促进作用;相反在鲜水河断裂带北西段、小江断裂带等历史地震频发的断裂带上,地震危险性具有一定的减速作用.更多还原

【Abstract】 Based on a 3-D active fault geometric model established for Sichuan--Yunnan region and long-term fault slip rate inverted from GPS and leveling data, we firstly calculated the coseismic deformation induced by the seismic dislocation of the 2008 Wenchuan earthquake. Then using the 3-D geometric model we inverted the deformation field for potential slip of each active fault. By comparing the calculated potential fault slip with the estimated long-term fault slip rate we inferred the influence of the Wenchuan earthquake on the seismic risk of the active faults. The results are as follows: the faults in eastern conjunction zone of Sichuan and Yunnan province, i.e., the southwestern segment of Longmenshan fault, the southern segment of Xianshuihe fault, Anninghe fault, Zemuhe fault, northern and southern segments of Daliangshan fault, and Mabian fault, have advanced their seismic risk of 305, 19, 12, 9.1, 18 and 51 years, respectively. As to the western conjunction zone of Sichuan and Yunnan province, we found the faults like Lijiang--Xiaojinhe fault, Nujiang fault, Longling--Lancang fault, Nantinghe fault, and Zhongdian fault, also got their seismic risk advanced. On the opposite, the faults, like the northwestern segment of Xianshuihe fault and Xiaojiang fault, become safer than before after the Wenchuan earthquake.更多还原