纪念古浪8级大震九十周年——暨对特大地震的研究讨论
Commemoration of the Ninetieth Anniversary of the Gulang MS8 Earthquake——Discussion of the Study of Great Earthquakes

置甘肃古浪8级地震发生90周年之际，本文用几种方法回顾性地讨论了特大地震的预测问题。分别用块体交界带指标、高山峰指标探讨了1920年海原8.5级地震发生的位置，并以这两个指标讨论了1927年古浪8级大震发生的位置。从国内某些大震25年周期的相关性和太阳活动峰年讨论了1927年古浪8级大震的发生年份。这些回顾性的指标研究对今后地震动，地震风险区划和预测大地震有一定的参考价值。
On the ninetieth anniversary of the Gulang, Gansu MS8 earthquake, in this paper, we retrospectively investigate and discuss the prediction of great earthquakes. We used two indexes, the block border zone and high mountain indexes, to research the location of the 1920 Haiyuan MS8.5 earthquake and the 1927 Gulang MS8 earthquake. We discuss the year of earthquake occurrence of the 1927 Gulang MS8 earthquake based on the relationship of the 25-year cycle for great earthquakes in China and the maximum solar background activity. Our retrospective study of these indexes provides a valuable reference for the study of earthquake ground motion and seismic risk regions for the prediction of great earthquakes.