Fuzzy rule-based expert system for short-range seismic prediction

In Switzerland, the 57 km long Gotthard base tunnel is being built as part of the AlpTransit project with a maximum overburden of 2000 m. Because of the difficult geological situation, an exploratory tunnel was set up to explore the Piora-Mulde, a possibly unstable carbonate rock zone in south Central Switzerland. A geophysical forecast system called tunnel seismic prediction has been designed by Amberg Measuring Technique Ltd. to explore the geology during the tunnelling process. But several difficulties occurred in interpretation of the seismic data in terms of geological forecasts. This paper describes a simple approach to geological interpretation of seismic diffraction stack images by using fuzzy logic. A fuzzy rule-based expert system was developed to classify lithologic and tectonic rock units by interpreting those seismic images. (C) 2002 Elsevier Science Ltd. All rights reserved.