The Study And Application Of The Method Of Three-dimensional VSP Multi-wave Joint Interpretation

As the difficulty of gas and oil exploration is increased, the regular technology of seism-exploration confronts many challenges : how to effectively reduce the multi-results of the exploration of pressure wave ,accurate positioning of small faults, reefs and buried hill , to distinguish bright spot between genuine and phony and improve the records of resolution a series of complex problems . To address this series of complex problems, the urgent needs for high precision and high reliability of the technology.In recent years, the exploration technology of 3D-VSP multi-wave has been considerable development. On the one hand, it Comparing with single press wave, multi-wave and multi-compose exploration technology offering information will increase in multiples and derive various combined-parameters, which makes it have reliability higher for estimating lithology and identifying fluid and avoids multiplicity of using pure press wave to forecast reservoir as possible. On the other hand , comparing with general seismic section, VSP has higher the signal noise ratio and greater penetration depth; VSP can easily observe three-component through well finestra , which contributes to observation and analysis for vector field in essence ; basing on it, VSP can not only use upgoing wave and downgoing wave, but also use p-wave, ps-wave , first-wave and the different origins wave; and reduce multi-results of seism datum inversion integration with offshore exploration.Nowadays the most important issue of 3D-VSP multi-wave seismic data interpretation is the multi-wave multi-component calibration and comparison, the most critical and most basic is the wavelet selection and level calibration; Secondly, how to identify fluid using multiple parameters after analysis of multi-component attributes. Confronting with those questions, this article mainly research includes the following :(1) To process the logs of data processing of p6 well in Qikou area;(2) Using the method of fractal and correlation extracts wavelet of minimum-phase and mixed-phase and synthetic seismograms by logging data, and then compared with the well profile and the level calibration, and converted wave section is compressed;(3) To compute the amplitude ratio and frequency ratio of modle of press and shear wave, its abnormity have been researched; the processed result of actual data of three-dimensional multi-wave in Qikou area shows that this method is some assistance for reservoir prediction;(4) For many argument (such as being poisson's ratio, lame constant and bulk modulus) reservoir prediction, the inversion lithology and spring parameter can be explain by contrast.