Abstract: Based on the analyses of grouped activities of deep-focus (m_b≥6.0) and shallow-focus (M_s≥5.0) earthquakes in Northeast China, the spatial and temporal correlation between the deep-focus "strong earthquake group" and shallow-focus "strong earthquake group" was studied. The study was focused mainly on the characteristics of earthquake distribution along the collision zone between the west Pacific plate and Eurasian plate, as well as its relation to the form of the west Pacific subduction zone. Moreover, emphasis was also laid on the analyses of the effect of the west Pacific plate on the seismicity in Eurasian plate. The results show that in the region where the west Pacific plate subducts at low angle, the seismicity along the plate collision zone is very strong, and the effect of plate subduction on the seismicity in Eurasian continent is most significant. In this condition, the subduction zone is subjected to relatively strong compressive stress. However, in the region where the west Pacific plate subducts at high angle, the seismicity along the plate collision zone becomes weaker, and the effect of plate subduction to the seismic activity in Eurasian continent becomes less significant. In this condition, the tensile stress produced by the subduction zone at depth is enhanced. We propose, therefore, that the seismic activity of Northeast China will enter the active period of shallow "strong earthquake group" in forthcoming 10 years. In this period, 6 earthquakes of M_s≥5.0 may occur in this region. It is emphasized that the monitoring and prediction of seismic activity in Northeast China should be enhanced.

Key words: strong earthquake group, west Pacific plate, earthquake trend, Northeast China

摘要： 分析中国东北地区深震(m_b≥6.0)及浅震(M_s≥5.0)的成组性活动特征,研究了深震"强震组"与浅震"强震组"的时、空相关性.着重探讨了西太平洋板块与欧亚板块碰撞带的地震分布特征及其与西太平洋俯冲带形态的关系,并着重分析了西太平洋板块对欧亚板块地震活动的影响.结果表明:西太平洋板块俯冲倾角小的地区,板块碰撞带地震活动强烈,板块俯冲对欧亚大陆的影响也较强,俯冲带处于较强的挤压应力状态;西太平洋板块俯冲倾角大的地区,板块碰撞带地震活动较弱,板块俯冲对欧亚大陆的影响也较弱,深部俯冲带引张应力增强.分析认为,未来10年中国东北地区将进入浅震"强震组"活动时段,期间可能发生M_s≥5.0地震6次左右,应加强东北地区的地震监测预报工作.

关键词: 强震组, 西太平洋板块, 地震趋势, 中国东北地区