A STUDY ON PHENOMENON OF DOUBLE EARTHQUAKES IN SHANDONG PROVINCE AND ITS ADJACENT AREAS

In this paper,a research is done on the phenomenon of double Earthquakes of moderate strong earthquakes in Shandong province and its adjacent areas.The obtained results indicate that:(1)double Earthquakes of M ≥ 4 moderate size earthquakes mainly concentrated in the strait of Bohai sea and Xingtai area and its nearby tectonic zone;(2)double Earthquakes of M ≥ 5 moderately strong earthquakes mainly distributed near the epicentral regions of nowaday and historical strong earthquakes(M ≥ 7) in the strait of Bohai sea,Xingtai area,Linyi area and Hezearea.It is considered that a relationship between double Earthquakes and Upper mantle uplift,fault development,complex tectonic and high stress condition is presented.