基于科学台阵的观测资料，计算了2016年门源6.4级地震前约2年震源区80km范围内105次1.5≤M_L≤3.3地震的视应力。结果显示，研究区域2015年1月13日～2016年1月20日的地震视应力明显高于2014年3月23日～2015年1月12日，视应力其特征表现为震前1年明显升高—明显降低—临震前2个月小幅升高，2个时段扣除震级影响的规准化视应力对比表明，震前1年研究区域应力水平相对升高，规准化视应力空间分布图像显示，皇城-双塔断裂附近存在显著高值异常区，距离震中约48km。视应力异常、平安水位和乐都气氡破年变异常表明，研究区域附近震前应力水平较高，与2016年门源6.4级地震前震源区应力场增强存在较好的对应关系，是1次测震和前兆异常显著的震例。视应力异常可在较长时间显示高应力水平状态和异常地点，前兆破年变异常可以从时间紧迫性给出判断，因此，结合可信度较高的测震和前兆异常可以给出一定程度的地震预测。

Using waveforms from the China Seismic Array,we calculated the apparent stress of 105 earthquakes with 1.5 ≤ M_L ≤ 3.3 within 80km radius of the epicenter about 2 years before the Menyuan M_S6.4 earthquake in 2016. The results show that,apparent stress between January 13,2015 to January 20,2016 was obviously high than that between March 23,2014 to January 12,2015,and apparent stress increased obviously about 1-year before the Menyuan M_S6.4 earthquake and decreased significantly,finally increased again about 2 months before the Menyuan M_S6.4 earthquake. We used the normalized apparent stress to deduct the effect of magnitude. The comparison of the normalized apparent stress of the two periods show that the stress level of the study area increased about 1-year before the Menyuan M_S6.4 earthquake. Spatial distribution of the normalized apparent stress shows that,the Huangcheng-Shuangta fault was a high value anomaly area which appeared 48km away from the epicenter of Menyuan M_S6.4 earthquake. The abnormals of apparent stress,Pingan water level and Ledu gas radon show a good corresponding relation with the increase of stress field and was a good seismometry and precursory earthquake case with significant anomaly. The abnormal of apparent stress can judge stress level and define anomaly area. Annual variation of precursory can judge the urgency of time,and therefore using seismometry and precursory anomaly together can make earthquake prediction to a certain extent.

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青海省地震科学基金（2019B05）、青海省地震科学基金（2016A01）、中国地震局震情跟踪定向工作任务（2020010118）共同资助