MULTIPLE-TRANSIENT SURFACE WAVE PHASE VELOCITY ANALYSIS IN EXPANDED f-k DOMAIN AND ITS APPLICATION

作者：Shen, Hongyan^*; Chen, Chen; Yan, Yueying; Zhang, Baowei

来源：Journal of Seismic Exploration, 2016, 25(4): 299-319.

• surface waves
• reflection seismic
• 2D Fourier transform
• phase velocity analysis
• dispersion curve
• near-surface structure

Surface waves are usually regarded as noise in traditional reflection seismic processing. However, useful and important signals can be extracted from surface waves since it still carries geological information. In this paper, we developed a new method of multiple-transient surface wave phase velocity analysis, which is based on 2D Fourier Transform theory. We established the equation of surface wave velocity analysis in expanded f-k domain to demonstrate the relationship among frequency, wave number, phase velocity, wavelength, and penetration depth. It is more convenient to obtain a relevant velocity spectrum by converting f-k spectrum into the depth-phase velocity (H-v(R)) spectrum. We obtained better results by extracting the phase velocity and depth information from the H-v(R) spectrum. This has the ability to extract the near-surface geological information with high accuracy and strong capabilities of de-noising. We used the new method to test an actual dataset for detecting active faults. The study shows that Rayleigh wave phase velocity has the ability to delineate structures in the near surface, about 150 m deep, which is very useful to deal with geological structures in Quaternary geology, such as bedrock fractures. The geological structures interpreted from the Rayleigh wave phase velocity profile and reflection seismic cross-section show a strong consistency.

• 出版日期2016-8
• 单位西安石油大学