2020年6月26日新疆于田6.4级地震发生在2020年度全国地震危险区内，震前作出了较好的中期（年度）和短期（月尺度和周尺度）预测，是少有的地球物理观测能力较低地区的强震前中期和短临预测较好震例。本文梳理了中期和短期预测的主要依据及其预测效能，研究表明，震前中期异常主要有流动地磁、多方法组合、5.0级地震平静打破、6.0级地震的准周期活动等；短期异常有4.0级地震活动图像、中源地震影响、于田垂直摆倾斜EW、于田GNSS基准站EW位移、和田GNSS基准站EW位移等。在总结震前分析预测过程的基础上，提出针对地球物理观测密度低地区的地震危险区论证和短临跟踪的建议，为该类地区的地震危险区判定及跟踪工作提供宝贵经验。

Before the Yutian M_S6.4 earthquake on June 26,2020 in Xinjiang Province of China some prospective and predictive seismicity and precursory anomalies have been found. In this paper,we systematically reviewed and summarized the earthquake forecasting procedure before the Yutian earthquakes. In terms of medium-term earthquake forecasting,the Yutian earthquake is located in the potential area of the annual earthquake hazard map provided by the China Earthquake Administration. It is encouraging that the occurrence time,location,and magnitude of the Yutian earthquake are well predicted. The medium-term forecasting is mainly based on the anomalies of mobile geomagnetic observation,combination of multi-methods(MMEP),seismic quiescence with M_S ≥ 5.0 and the quasi periodic characteristic of earthquakes with M_S ≥ 6.0 in this region. In the shot-term stage before the Yutian earthquake,the main anomalies are from seismicity patterns with M_L ≥ 4.0,the alert of the intermediate-depth earthquake occurrence,the vertical pendulum tilt meter at Yutian seismic station,the displacement changes in EW direction of Yutian and Hetian GNSS stations. For the Yutian earthquake,the geophysical anomalies as measured by sparse monitoring stations around,were evidently considerable precursors. These practical experiences allowed us to respond to and to conduct earthquake forecasting opinions quickly and efficiently. At last,we discussed lessons learned from the Yutian earthquake forecasting,including forecast procedures and identify both the seismicity and observed geophysical precursors before earthquake occurence.

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中美合作项目（2018YFE0109700）和震情跟踪面上项目（2020020101）共同资助