关键词: 近地表勘探, 面波数据处理, 面波频散, 能量谱计算

Abstract: The energy spectrum precision of surface wave dispersion is an important factor affecting the acquisition of near-surface cross-wave velocity, and the effective extraction of surface wave dispersion curve is an important link of the subsequent inversion stratigraphic structures and medium physical parameters. The article discusses the basic principle of seven different wave dispersive energy spectrum methods, including τ-p transform, high resolution linear Radon transform, frequency decomposition, phase shift transform, frequency wavenumber transform, slant frequency wavenumber (SFK) transform, and vector wavenumber transformation methods. Through the modeling with a three-layer horizontal layered models with velocity increasing with depth and by using the above-mentioned methods to generate surface wave dispersive energy imaging, the energy spectra are calculated and compared with the theoretical dispersion curves. According to the obtained scattered energy spectra, the characteristics and applications of different methods in data processing are analyzed. The results show that the precision of dispersion curve extracted by high-resolution linear Radon transform and vector wavenumber transformation method is better; the precision of the dispersion curve extracted by frequency wavenumber transform is the lowest,  the low-frequency information and the high-frequency information cannot be effectively identified; the SFK transform and high resolution linear Radon transform have strong anti-noise performance; the calculation of τ-p transform, frequency wavenumber transform and phase shift transform is shorter than that using other methods. 

Key words: near surface exploration, surface wave data processing, surface wave dispersion, energy spectrum calculation