Abstract: We analyze moderate-strong earthquake activities in Xinjiang within 3 years after earthquakes with magnitude 7 or so in the Northeast edge of Pamir—West Kunlun area since 1950, and discuss further seismic activity in Xinjiang after the 2008 Yutian M_S7.3 earthquake and Wuqia M_S6.9 earthquake. Our study shows that strain energy in Xinjiang released fully after the earthquakes with magnitude 7 or so since 1950 in the Northeast edge of Pamir—West Kunlun area, and no strong earthquake with magnitude over 6.5 occurred within 3 years after these earthquakes with magnitude 7 or so; the annual frequency of M_S≥5 earthquakes in Xinjiang appears downtrend within 3 years after these earthquakes with magnitude 7 or so, and the differential character of seismicity—quiescence of M_S≥5 earthquakes after the 2008 Yutian M_S7.3 earthquake is similar to that after the 1974 M_S7.3 earthquake of Uzbel Mountain pass and the 1996 M_S7.1 earthquake in the Karakorum Mountain pass. In addition, Combining dynamic condition of strong earthquake activities in Xinjiang and focal mechanism feature of the earthquakes of magnitude 7 or so in the Northeast edge of Pamir—West Kunlun area , we discuss possible causes for spatial activity features of moderate-strong earthquakes in Xinjiang within 3 years after magnitude 7 or so earthquakes.

Key words: Moderate-strong earthquakes, Activity state, the Northeast edge of Pamir-West Kunlun area, Yutian M_S7.3 earthquake