Therefore,Moho behavior in the depression can be revealed by the long cable seismic section.

Seismic migration is a main tool to improve horizontal resolution of the deep seismic reflection data.

Since then many other countries have carried out deep seismic reflection researches.

International geologists have recognized deep seismic reflection as high technology in probing fine structure of lithosphere.

The key to the processing of deep reflection seismic data seems to be the cxtraction and enhancement of deep weak effective signal from the disturbing background, thus arising the signal-to-noise ratio and resolution ratio of the profile.

The present paper has dealt systematically with a practical and effective deep reflection seismic technique—small-scale wide line reflection seismic technique.

The basin-range junction zone has complex surface geological conditions and a rather undulate tomography,where deep seismic reflection data are characterized by a low S/N ratio,strong multifold noises and great lateral variation in velocity.

Deep seismic reflection profiling across Jiashi strong earthquake swarm region has revealed fine crustal images through to M-discontinuity of the studied area.

The mid-crustal reflection formed by the Main Himalayan Thrust (MHT)is interpreted to be underthrust gradually northward beneath the crust of southern Tibet by intensive processing of the data of two N-S-trending deep seismic reflection profiles on the southern side of the Yarlung Zangbo River obtained by Project INDEPTH II in 1993.

Results of seismic deep reflection,high resolution refraction and shal- low artificial seismic exploration indicate that the fault on the northern bank of the Weihe river is composed of two branches:one is the Yaodian-Zhangjiawan fault and the other is the Chuanzhang-Zuitou fault.