Abstract：Comparing with ordinary VSP,the SWD VSP has its feature and distinctive superiority.It uses the noises produced by drill bit during drilling pro-cess as a source for inverse VSP survey character-ized by without interference of drilling and occupa-tion of drilling time,no risk of damaging borehole,and especially having capability of real time pre-dicting structural details of strata ahead of bit by in-site seismic image processing.The key tech-niques are how to accurately acquire and restore weak seismic signal produced by bit under the background of strong interference noises at wellsite and to transform these signals into equivalent pulse response of horizons.The paper introduced the ba-sic principles of VSP technique and key techniques used,it is shown through analyzing the results of roller bit SWD VSP data processing in Lun-Gu 47 well and making correlation with the surface seis-mic section passing through the well that the ac-quisition and processing techniques used in paper can obtain seismic imaging section corresponding to 3D surface seismic data,having good popularized application prospect.
