The Study in the Application of FFT in Vibroseis Data Harmonic Filtering

Abstract

This paper studies the thesis of slip-sweep acquisition method in vibroseis exploring. First of all, it briefly describes slip-sweep acquisition in principle, operation and signal processing, compared with the bomb exploring and conventional cascaded sweep acquisition and analyzes the principle of vibroseis exploration in detail. Then the reason why harmonics generated is analyzed. Among the harmonics, high frequency harmonics is most serious. Based on extensive research on the theory and the numerical experiments, the paper assumes that the energy of the high frequency harmonics and that of the original stimulated signal into a linear relationship. According to this assumption, a mathematical model to filer out high frequency harmonics is established. After generating standard high frequency harmonics through frequency doubling and estimating the ratio of the energy of each harmonic and fundamental, the mathematical model perfectly matches actual seismic data processing, that is, an effective way of vibroseis data processing. Finally, the paper developed full procedures of slip-sweep vibroseis data processing and made all the programs. With a fast processing speed and obvious effect, the programs achieve good application; fully meet the industrial demand to process vibroseis data.