关键词: 前兆异常形态特征, 地区性, 象限性, 强震短期预测

Abstract: Based on the analysis for characteristics of multi-precursor anomaly patterns of 31 earthquakes with M_S 5.0 occurred in North China since 1970, some results are extracted as follows: 1. In short-term and impending stage, it is universal that deformation precursors and water level precursors are emerged in quadrant distribution, which is related to the focal mechanism. In compressional area, deformation and water level precursors show ascending types. But in expansionary area, they descent down; 2. The types of tilt anomalies are different in different areas. Before most of strong earthquakes, the tilt anomalies near the source incline opposite to the epicenter, while the ones far from the source incline toward the epicenter; 3. Most of the apparent resistivity anomalies show descending types. Water (gas) chemistry anomalies usually go up in the short term and descent down in the impending term. Base on the comprehension for the characteristics of earthquake precursors' patterns, we proposed an idea regarding determining the location of the coming strong earthquakes and the seismogenic state.

Key words: Characteristics of precursory patterns, Regional feature, Quadrant feature, Short-term strong earthquake prediction