Sawasdee Yordkayhun

pp. 477 - 485

Abstract

In environmental and engineering studies, detecting shallow buried objects using seismic reflection techniques is
commonly difficult when the acquisition geometry and frequency contents are limited and the heterogeneity of the subsurface is high. This study demonstrates that such near-surface features can be characterized by taking advantage of P-wave
traveltimes of seismic data. Here, a seismic experiment was conducted across a buried drainpipe series, the main target, with
the goal of imaging its location. Tomography is implemented as an iterative technique for reconstructing the P-wave velocity
model from the first-arrival traveltimes. To study the reliability of the method, a set of starting model was tested and a
synthetic data was generated. After evaluation and selection of the best model, the resulting image was interpreted. The low
velocity zone in the tomographic image coincides well with the location of a drainpipe series and surrounding altered ground
due to its installation. The existence of buried objects at the test site confirms and demonstrates the potential of the method
application.

Keywords

• seismic tomography
• traveltime
• inverse theory
• near-surface object