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根据历史地震记载、近期地震活动性和构造应力场资料，分析了北京西北延庆－怀来盆地的潜在地震危险性。指出自１９９５年７月２０日至１９９６年７月３０日发生于延庆－怀来盆地的ＭＬ＝４１地震序列的震源分布，揭示了分布于延庆－怀来盆地的两条共轭断层，位于这两条共轭断层延长线交汇处的怀来县城地区具有断层闭锁区的特征，该闭锁区域的线性尺度与一个６０级地震震源区的线性尺度相当，但延庆－怀来盆地近期微震活动未显示出该闭锁区在近期内将发生中强地震的征兆。对ＭＬ＝４１地震序列引起的地面运动的研究表明，该地震序列的震源谱可以用ω２模型表示，并且延庆－怀来盆地的品质因子ＱＳＨ值非常低，介于１４０与３６０之间，特别是在近震源地区ＱＳＨ值最低，只有１４０。
Based on historical seismic records, recent seismicity and tectonic stress field data, the potential seismic risk of the Yanqing-Huailai Basin in northwestern Beijing is analyzed. The focal distribution of ML = 41 earthquake sequence occurred in Yanqing-Huailai Basin from July 20, 1995 to July 30, 1996 is pointed out, revealing two conjugate faults distributed in Yanqing-Huailai Basin, The area of Huailai county located at the intersection of the extension of these two conjugate faults has the characteristics of fault lockup area. The linear scale of this block area is equivalent to the linear scale of a 60 earthquake focal zone, but the Yanqing-Huailai Basin recent Microseismic activity has not shown any sign of moderate to strong earthquakes in the area to be closed in the near future. The study on the ground motion caused by the ML = 41 earthquake sequence shows that the source spectrum of the earthquake sequence can be expressed by the ω2 model, and the QSH value of the quality factor in the Yanqing-Huailai Basin is very low, between 140 and 360. Especially in the near epicenter QSH lowest value, only 140.