Coal seismic diffraction fault imaging: results from numerical modelling

Abstract

Faults are the most important structures which need to be detected for any modern underground coal mining projects. Even a fault with a throw of a few metres can create safety issues and lead to costly delays in mine production. While locating faults with throws greater than 5-10 m has been generally accepted for seismic surveys, techniques to resolve the more subtle faults, shears and features which exploration programs should also locate are needed. Faults cause breaks in continuity of seismic horizons. These discontinuities generate diffraction patterns. Before the days of seismic migration and generation of very high fold data, diffraction patterns were what the seismic interpreter sought as an indication of faulting, especially for small faults where the discontinuities of the seismic reflections are less evident but most processing is now aimed at suppressing these diffractions. However, in recent years, techniques for diffraction imaging developed for petroleum seismic data processing, makes small fault detection possible by separating the diffraction events from the reflection seismic events. In this paper, we will develop new algorithms for extracting fault related diffractions from reflection seismic data and providing a new way to detect faults especially the small ones from coal seismic data and demonstrate the feasibility of the newly developed fault imaging algorithms with numerical examples in the coal mining environments.