中文摘要：

将双差地震定位法与遗传算法相结合,对2001～2007年甘东南地区的地震进行了重新定位。结果显示：重新定位后地震在空间分布上更加集中,部分地区的地震有向构造带趋近的变化。地震震源平均深度为14.6km,5～20km深度为该区多震层深度范围。3次5级以上中强地震的震中均处于主干活动断裂边缘。震源深度分布与断裂构造的关系刻画出剖面沿线不同断裂的深部展布特征,部分断裂延伸到中、下地壳。

英文摘要：

We relocate earthquakes occurred in the southeast area of Gansu from 2001 to 2007 using double-difference method and genetic algorithm method.The result shows that the earthquakes are more spatially concentrated and in some areas the earthquakes tend to get close to tectonic belts.The average hypocenter depth is 14.6 km and the seismogenic layer ranges from 5 km to 20 km.After relocating three moderately strong earthquakes,we find that they were all occurred in the edge of the main active faults.The relationship between seismic depth distribution and fault structure portray the spreading characteristics of different faults along the profile in the deep,and some faults stretch to the middle and deep crust.