ALBERT

Description: A new method for the analysis of folding of seismically mapped horizons is described. Based on a model of developable surfaces, the local geometrical properties are determined by analyzing the variation of dip and strike along linear strips on the surface. By considering strips in different directions, a plunge line (the approximation to the generatrix of a developable fold) is identified as the direction associated with the least variation of surface attitude. The map pattern obtained by analyzing the plunge and trend of plunge lines across an area allows the identification of domains where folding accords with a developable geometry. Such domains are recognized from straight plunge lines, defining convergent or parallel patterns. Deviations from these patterns correspond to regions of structural complexity associated with ductile or brittle straining of the horizon. We suggest that plunge-line analysis may offer a useful technique for automatic fault recognition. After his bachelor's degree in geology (Birmingham, 1969), Richard Lisle went on to specialize in structural geology at the Royal School of Mines, Imperial College (M.Sc., 1969; Ph.D., 1974). He has held posts at the Universities of Leiden, Utrecht, and Swansea and now is professor of structural geology at Cardiff University, Wales, United Kingdom. His research lies in the frontier area between geometry and geological structures.After graduating in mining engineering at the University of Oviedo, Juan Luis trained as a petroleum engineer (École Nationale du Pétrole et des Moteurs, Paris, 1988; Imperial College, Royal School of Mines, London, 1989). After some years working as a computing engineer in petroleum software in France, he gained a Ph.D. in mining engineering in Oviedo in 1994 and joined the Mathematics Department. He currently works on geomathematical methods: geostatistics, inverse problems in geophysics, fold modeling, digital imaging processing, and finite-element methods.