| Seismic while drilling (SWD) is a new technique rapidly developed recently, which can be used to make seismic survey using the drill-bit vibration as down-hole energy source and forecast the detail geological structures ahead of the drill-bit so as to reduce the drilling risks. It is a kind of reverse VSP, so sometimes we call it Vertical Seismic Profile While-Drilling, or Drill-Bit VSP. It has the advantages that the surface seismic survey or VSP has, and also has its own characteristics of no interruption to drilling, no lost rig time, and no risk for the borehole while the data set is being acquired, as well as has high efficiency. Specifically, subsurface conditions ahead of the drill bit can be predicted immediately during drilling without drawing the bit out of the hole, and seismic images are available at the well site for real-time survey so as to reduce the drilling risks, which is the main target of the SWD survey. Based on analyzing the technical developing of SWD abroad and home, this paper systematically dissertated and summarized the SWD basic theories, the acquisition method, and the data processing as well as our research. According to the technical problems, this paper studied and developed pilot signal deconvolution, wavelet deconvolution with multi-channel statistics and strong noise attenuation based on the best adaptive least-mean-square (LMS) theory with linear restriction, and successfully applied above techniques to the real SWD data acquisition and data processing, which have following breakthrough and innovations: 1. It is the first time systematically studying the traveling characteristics of all the maim SWD seismic P-waves including the direct arrival, reflection, and other disturbing wave modes that are not typically observed. According to the difference of above traveling characteristics of SWD seismic waves, this paper also discussed the methods of above-mentioned noise attenuation or separation, and their application have gained good results, which illuminated the real values of above research and its directive significance for the SWD survey. 2. How to attenuate and eliminate the strong noises produced by all activates around the well from the SWD data and recover the weak reflections are always the key technique in the SWD data processing. This paper studied and developed a new noise attenuation methods based on the best adaptive least mean squire theory with linear restriction by through studying the produced sources of all strong noises. The application of above methods in real SWD data processing demonstrated that the result after application got ideal effect, and most of the strong noises have been disappear, moreover haven't affected effective signal. Compared with the conventional noise attenuation methods, like F-K filter, Ï„-p filter, the new method got better result and is a key technique in SWD data processing, which was developed by myself exclusively. 3. The influence of the drilling string to the drill-bit signal is inescapable, especially to the portion of 30-40 Hz of the signal, which was well known by B.B.Weatherby, etc. as early as 1936, but how to eliminate the influence is always a big problem. Through combining the deconvolution with noise attenuation...
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