针对2013年7月22日甘肃岷县-漳县M_S6.6地震前观测到的地震活动性与地球物理场观测异常，总结了震前的显著地震活动异常和地球物理场观测异常演化特点。在地震活动性方面，震前存在大范围5级地震平静被打破，5级地震空区、4级地震空区和3级地震平静被打破等显著异常；在地球物理场观测异常方面，新增异常数量自2010年开始逐渐增加，在2011年年中达到最大值；异常测项比在震中距50～150km范围内最高；异常的时空演化存在明显的3阶段特征，即α阶段异常具有向外扩展的特征；β阶段表现为短期内大范围出现异常；γ阶段表现为远源区的异常向震中收缩（γ₁）和近源区的异常向外扩展的特征（γ₂）。对这些异常的演化特点的认识可以直接指导地震跟踪预测工作，如震前出现的地震活动（如不同震级的地震空区嵌套）和地球物理场观测异常分布区域对发震地点具有一定预测指示作用；中小地震活动的异常图像（如3级平静、4级空区）和显著短期异常（如地球物理场观测趋势异常的群体准同步的转折异常、异常的时空迁移性、短期群体异常等）对发震紧迫性具有一定指示意义。

In this paper, the seismic activity and observations in geophysics anomalies detected before the Minxian-Zhangxian M_S6.6 earthquake of July 22, 2013 in Gansu Province were summarized. In terms of seismic activity, there were significant anomalies. For example, the large-scale M_S5 seismic quiescence is broken, M_S5 and M_L4 seismic gaps are broken, and M_L3 seismic quiescence is remarkably disturbed. In terms of observation in geophysical anomalies, the number of new anomalies in precursors has gradually increased since 2010 and reached the maximum in mid-2011. The ratio of anomaly items is the highest in the range of distance in 50～150km from the epicenter. The spatial-temporal evolution of observations in geophysical anomalies has obvious three-stage characteristics, that is, the α-stage anomaly has the characteristics of outward expansion, the β-stage manifests itself as a large-scale anomaly in a short period; the γ-phase manifests itself as an anomalous to epicenter contraction in the far-source region (γ₁), and the characteristics of the anomalous outward expansion of the near-source region (γ₂). The understanding of the evolutional characteristics of these anomalies can directly guide the earthquake tracking and prediction work, such as the seismic activities occurring before the earthquake (such as the seismic gap nesting of different magnitudes) and observations in geophysical anomaly distribution area have certain predictive indications for the earthquake location. Anomalous images of small and moderate-scale earthquakes (such as the M3 seismic quiescence and M4 seismic gap) and significant short-term anomalies (such as the quasi-synchronized transitional anomalies of the observations in geophysical anomalies, the temporal and spatial migration of precursors, short-term population anomalies, etc.) have certain guiding significance for the urgency of earthquake occurence.

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中国和美国政府间合作项目（2018YFE0109700）资助