Abstract: Shallow seismic surveying is a common method applied to the research of blind fault activity at the Quaternary stratum region,especially in urban area.The bifurcating,uniting,bending,intermitting and ending off of reflection waves on stacked time section are important signs which are often used to judge the existence of blind fault.At the northern area of Songhuajiang River in Harbin City,we finished two seismic reflection profiles.On the shallow seismic reflection profiles of Lugangtun and Jubaotun,the T₀ wave group corresponding to the interface between Cretaceous sand-mud stone and lower Pleistocene gravel is clear.T_0-1 reflecting wave group corresponding to the contact surface between gravel and clay,or fine sand and gravel,is also clear.Based on the stacking seismic profiles and borehole data,we conclude that the Ashihe fault offset the bottom stratum of lower Pleistocene,and Binzhou fault cut off the bottom stratum of upper Pleistocene.By building high quality composite drilling geological profiles,dating the samples from bores,and contrasting stratum from one bore to the other,we consider that the Ashihe fault does not offset the Quaternary formation,the fault may only exist in Cretaceous sand-mud stone.The Binzhou fault is only an early Pleistocene fault;it doesn't offset the late Pleistocene formation.Finally,we think that the bifurcating,bending,intermitting and ending off of seismic reflection wave group on Luegangtun and Jubaotun seismic profiles are not the result of fault activity,but the phase change of Quaternary formation.

Key words: shallow seismic surveying, bore, stratigraphical analysis, Quaternary

摘要： 浅层地震勘探是第四系覆盖区隐伏断层活动性研究常用的手段,叠加剖面上反射波组的分叉、合并、弯曲、中断、尖灭等被用作判断断层存在的重要标志。松花江北的吕刚屯、巨宝屯浅层地震叠加剖面上,T₀为下更新统砂砾石层等松散堆积和白垩系砂岩、泥岩的分界面,反射波组清晰。T_0-1波组为砂砾石层和黏土层、或砂砾石层和粉细砂层的反射界面,反射波组振幅大,能量强。根据地震反射剖面和测线上的钻孔资料,认为阿什河断层错断了下更新统下段,滨州断层错断了上更新统下段。而通过建立高精度的钻探联合地质剖面、地层年代测试和地层对比,确认阿什河断层没有错断第四系,滨州断层错断了下更新统下段。最后,从第四系的岩性、厚度变化等解释了浅层地震叠加剖面上反射波组的中断、弯曲并非断层活动的结果,而是由第四纪地层相变引起的。

关键词: 浅层地震勘探, 钻孔, 地层分析, 第四纪