【摘要】 对 1970年以来宁夏“固原窗”的 M_L≥3.0地震活动增强与南北地震带中北段的 5级以上地震之间的关系进行了深入剖析，发现 1970 年以来发生在距离“固原窗”300～500 km 范围内的 6 级以上地震与“固原窗”内 M_L≥3.0地震活动增强显著相关，其中大部分 6 级以上地震发生在“固原窗”的 M_L≥3.0 地震活动增强结束 1.1 年之内，少部分 7级以上地震发生在“固原窗”的 M_L≥3.0地震活动增强之前 0.5年，成组的 5级地震发生在“固原窗”的 M_L≥3.0地震活动增强过程中。更多还原

【Abstract】 In this paper, the relationship between the increased seismic activity of earthquakes with M_L≥3.0 in"Guyuan window" and the earthquakes with M_S≥5.0 in the middle and northern section of the North-South seismic belt since 1970 has been analyzed. It is found that since 1970,earthquakes with M_S≥6.0 occurring in the region300-500 km away from the "Guyuan window" are significantly correlated with the increase of seismic activity with M_L≥3.0 in"Guyuan window" . Most earthquakes with M_S≥6.0 occurred within 1.1 years after the end of seismic activity enhancement of earthquakes with M_L≥3.0 in the "Guyuan window",a small number of earthquakes with M_S≥7.0 occurred 0.5 years before seismic activity enhancement of earthquakes with M_L≥3.0 in the "Guyuan window",a group of M5 earthquakes occurred during seismic activity enhancement of earthquakes with M_L≥3.0 in the "Guyuan window".更多还原