Relationship between Tectonics and Small to Moderate Earthquakes in Guye and Luanxian area,Hebei Province

Small earthquake activity is closely associated with fault movement,and small earthquake location method is commonly used for earthquake fault rupture and seismogenic structure research.Using double difference algorithm,earthquakes occurred from 1978to2011 are relocated.On the basis of seismology and active tectonics,focusing on Tangshan earthquake tectonic system and Luanxian earthquake tectonic system,we discover a new earthquake belt in the east of Guye area through the spatial-temporal analysis of the plenty of consecutive small earthquakes,and we speculate there exists a deep fault of NNE-striking,which is coordinated with the linear feature and coal seams distribution features.The speculated fault coincides with the Xujialou fault from the coal field geological exploration data,which is considered to trigger the MS4.2and MS4.8earthquakes in the past 3years.We suggest the earthquake monitoring on this region should be strengthened and active tectonic research about the speculated fault should be carried out.