High resolution seismic imaging of the near-surface : comparison of energy sources

• Main Author: Xiang, Jianguang
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2000
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/985/; https://research.library.mun.ca/985/1/Xiang_Jianguang.pdf; https://research.library.mun.ca/985/3/Xiang_Jianguang.pdf

The shallow seismic reflection method plays an important role in helping to understand engineering, mining and environmental problems. For high resolution at shallow depth, choosing a seismic source to best meet the goals of the survey can be the most pivotal decision. This research is to study the characteristics of various portable and environmentally friendly seismic sources by comparing them to the source character of a shotgun source. The sources include two SIST (Swept Impact Seismic Technique) vibrators and a hammer. Data were collected in 1999 near St. John's, Newfoundland. They were compared with shotgun source in terms of radiated frequency spectrum and energy levels in an attempt to improve the resolving power. -- Compared to the shotgun data, the SIST vibrators provide lower frequency range but higher frequency bandwidth. Their weaker energy limits the effective penetration depth for imaging to 150 m. However, the SIST vibrator yields a higher resolution in stacked section than the shotgun. Based on its overall performance, the SIST vibrator shows a great deal of potential to be a viable, environmentally friendly seismic source with high resolution capability. This is especially suitable for environmental surveys, in which depths are usually not more than 200 m.