On the basis of quadrant features of the precursors in geo-electricity and deformation in the case of Tangshan earthquake and Datong earthquake in North China, the same feature of geo-electricity and deformation precursors before Zhangbei earthquake has also been found. It seems that the existence of the quadrant behavior is not accidental, which might be related to existence of the earthquake generations. It is known in terms of rock experiment and theoretical analysis that there exists actually quadrant feature in earthquake-generating process with the range of quadrant spatial distribution unfixed, showing features of ″gradual increasing → maximum → lessening slightly″, and showing that the increasing zone and the decreasing one (or compressing zone and expanding one) of the quadrant in the near-source region could be different from that in the region for from the source. Based on the knowledge of quadrant characteristics of earthquake precursors and analyzing the spatial distribution of different precursory anomaly types, which may be possess some reference meaning to the earthquake occurring region.%在总结华北北部地区唐山、 大同地震前地电阻率和形变前兆的象限性特征的基础上，分析并发现张北地震前的形变和地电阻率前兆也具有一定的象限性特征．说明前兆象限性的存在并非偶然，是与孕震体的存在有关．通过岩石实验与理论分析认为，在孕震过程中，前兆异常确实存在象限性特征．象限性的空间分布范围并不是固定不变，而是具有“逐渐变大—最大—变小”的过程．并且象限性的上升区与下降区（或压缩区与膨胀区）在近源区与远源区不同．如果基于对前兆象限性的认识，指导分析前兆异常不同形态异常的空间分布，对地震的可能发震地区预测将具有参考意义．
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