用两种发震构造的破裂位移分布模型对2008年汶川地震造成的区域主要断裂的库仑应力变化进行了模拟.通过对这两种破裂位移模型模拟结果的对比分析,表明破裂位移模型的逆冲兼右旋滑动的位移模式及南北两段分别有两个滑动量高值区这样的特点控制了区域库仑应力变化的总体分布特征.汶川地震的余震分布和计算结果还显示:所获得的区域主要断裂的库仑应力变化分布和正应力变化分布同时控制了该地震发生后余震的分布,库仑应力变化增强同时断层面受到主震断层位错拉张的区域和余震的分布强烈吻合,而库仑应力变化增强但是相应部位断层面受到主震的挤压作用却没有余震发生,显示了强震后区域断层受到的正应力变化和库仑应力变化均对余震的发生起到了重要作用,而不仅仅是库仑应力变化增强是触发余震的机制；两种模型计算结果的细微差异显示了倾角向下变缓的震源破裂模型能更好地解释余震在破裂断层北部的分布特点.对昆仑山断裂、鲜水河断裂等周边强震多发断层的库仑应力变化及对未来地震活动的可能影响进行了初步评价.%Two co-seismic displacement models were used to simulate the Coulomb stress change caused by the 2008 Wenchuan earthquake. Simulating results of these two models indicate that the common characteristics of the rupture faults with thrust and right lateral displacement and two respective areas in northern and southern part with high slipping values control the Coulomb stress change distribution. Comparing the aftershock distribution of Wenchuan earthquake and simulating results, we discover that not only the Coulomb stress change distribution influences the aftershock distribution, but also the normal stress change distribution must be paid much attention to, I. E. Those faults with Coulomb stress increasing and normal stress decreasing are to a large degree consistent with aftershock distribution, while those faults with Coulomb stress increasing and normal stress increasing almost have no aftershocks. Other unapparent differences between two simulating results indicate that the model with a rupture fault steep in shallow part and gentle in deep part can better explain the aftershock distribution, especially in the northern area of the whole seismic belt. Coulomb stress changes in some faults where strong earthquakes often occur, such as Kunlun fault and Xianshuihe fault, are analyzed to tentatively evaluate the likely influence on future seismicity of these areas.
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