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采用已公布的5个震源破裂模型,计算了Ms8.0汶川地震产生的库仑破裂应力变化,分析了应力变化与后续地震活动空间分布的相关性.以震源模型引起的不确定性分析为基础,研究了汶川地震在周边断裂上引起的库仑应力变化,并重点探讨了应力变化引起的地震活动性随时间的相对变化趋势.结果表明,以Ji模型和王卫民模型计算出的应力变化空间分布较好地与后续地震活动的空间分布相对应.最大的应力减小区主要分布于震源断层的东西两侧,最大的应力增加区分布于震源断层面以及断层面南北两个端部的邻近区域,此外还有一个北西-南东向的显著增加区位于主震断层面南段附近的汶川-映秀一带,该区域已发生了较多的余震活动,且地震活动呈现继续扩散的趋势,是未来地震危险性较高的地区.汶川地震引起了周边多数断裂不同程度的地震活动性增强,活动性增强最显著的是彭县-灌县断裂和青川断裂,未来100年内都维持在震前的2倍以上,地震活动恢复至背景水平所需的时间基本都达到800～900年;西秦岭南缘断裂、龙泉山断裂、鲜水河断裂、玉龙希断裂、安宁河断裂、岷江断裂和阿坝断裂的地震活动性受汶川地震的影响较小,震后地震活动率与震前相比不足2倍,并且扰动恢复时间较短.因抚边河断裂和虎牙断裂处于应力减小区域,未来地震活动性可能会减弱.受到汶川地震产生的应力变化影响,青川断裂和彭县-灌县断裂的未来发震危险性较高.
Based on the five provenance rupture models that have been published, the Coulomb rupture stress changes in Ms8.0 Wenchuan earthquake are calculated, and the correlation between stress changes and spatial distribution of subsequent seismic activity is analyzed.Based on the analysis of the uncertainty caused by the hypocenter model, The change of Coulomb stress caused by the Wenchuan earthquake on the surrounding faults was studied, and the relative trend of seismic activity with time was mainly discussed.The results show that the spatial distribution of stress calculated by Ji model and Wang Weimin model is better Corresponds to the spatial distribution of subsequent earthquakes.The maximum stress reduction zone is mainly distributed on both east and west sides of the focal fault and the largest stress increase zone is located in the vicinity of the focal fault plane and the north and south ends of the fault plane. There is also a NW-SE directionally significant increase in the Wenchuan-Yingxiu area near the southern section of the main seismic fault where more aftershocks have occurred and the seismic activity has continued to spread, which is a potential earthquake hazard in the future The area with higher sexual level caused by the Wenchuan earthquake caused more seismic activity around the majority of the fractures, with the most enhanced activity The Pengxian-Guanxian fault and the Qingchuan fault are both over two times the magnitude of the earthquake in the next 100 years, and the time required for the seismic activity to reach the background level basically reaches 800-900 years. The southern margin of the western Qinling fault, Seismic activities of the Longquanshan, Xianshuihe, Yulongxi, Anninghe, Minjiang and Aba faults are less affected by the Wenchuan earthquake. The post-earthquake seismicity ratio is less than 2 times that of the pre-earthquake and the disturbance The recovery time is short, the future seismic activity may be weakened due to the stress collapse of the Fubian River fault and the tiger tooth fault, and the future earthquake risk of the Qingchuan fault and the Pengxian-Guanxian fault will be affected by the stress changes caused by the Wenchuan earthquake Sex is higher.