随钻VSP技术研究及初步应用效果

随钻VSP技术与常规VSP技术相比，具有其自身的特点和独特的优越性，它利用钻井过程中钻头振动产生的噪声作为震源进行逆VSP测量，不干扰钻井，不占用钻井时间，对井孔无任何风险，特别是可以通过现场地震成像处理，实时预测钻头前方地层的构造细节，达到减少钻探风险为主要目的。其技术关键是如何在井场强干扰噪声背景下准确地采集和恢复弱钻头反射信号，并使之变成等效的地层脉冲响应。本文介绍了随钻VSP技术的基本原理和使用的关键技术，通过对轮古47井牙轮钻钻头随钻VSP资料处理成果的分析和与过井地面地震剖面的对比，表明文中所使用的采集、处理技术，可以获得与三维地面地震相当的地震成像剖面，具备良好的推广应用前景。

Studying SWD VSP technique and results of its preliminary application

Comparing with ordinary VSP,the SWD VSP has its feature and distinctive superiority.It uses the noises produced by drill bit during drilling process as a source for inverse VSP survey characterized by without interference of drilling and occupation of drilling time,no risk of damaging borehole,and especially having capability of real time predicting structural details of strata ahead of bit by in-site seismic image processing.The key techniques 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 basic 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 seismic section passing through the well that the acquisition and processing techniques used in paper can obtain seismic imaging section corresponding to 3D surface seismic data,having good popularized application prospect.