Probably the first documentation of an analogue experiment to simulate a geological process was presented in the Transactions of the Royal Society of Edinburgh by Sir James Hall [Hall, 1815]. Here, he described his first attempts to model folds observed in geological strata. Two experiments were performed. In the first experiment, several pieces of cloth, linen and woollen fabric were spread out on a table, one above the other. A flat door was put on top of the layered stack, being loaded with weights, to confine the stack. Next, two boards were applied to the sides of the stratified mass and were subsequently forced towards each other. This resulted in the gradual uplift of the heavy door, while the strata were constrained and adopted upward and downward bending folds. In the second experiment, beds of clay confined in a box were subjected to lateral compression due to movement of movable ends driven by screw jacks, which is basically the same experimental design as is still in use today for fold and thrust type experiments. This experiment resulted in the generation of folds in the strata. The similarity between the folds reproduced in the experiments and folds observed in natural strata led the author to conclude that folds observed in nature must have a similar origin as in the experiment and therefore are the result of horizontal compression. This hypothesis had already been proposed by de Saussure [1796], where he spoke of a lateral push as the cause for shortening and folding of rocks in the Alps. This experiment illustrated over almost two centuries ago the potential of analogue modelling techniques to understand geological structures.

Since the pioneering experiments in the early 1800’s, several other modellers followed in the late 1800’s studying fractures, folds and thrusts [e.g. Favre, 1878; Daubre, 1879; Schardt, 1884; Cadell, 1889; Willis, 1893]. In the 20th century, analogue modellers started to investigate a wider range of geological problems with similar modelling techniques [Mead, 1920; Link, 1930; Escher and Kuenen, 1929; Kuenen and de Sitter, 1938; Nettleton and Elkins, 1947; Hubbert, 1951; Cloos, 1955; Parker and McDowell, 1955; Ramberg, 1955; Oertel, 1962].

A major step forward in analogue modelling came with the advent of a well-founded scaling theory for analogue modelling of geological processes, provided by Hubbert [1937]. This theory revolutionised analogue modelling by changing it from a descriptive tool to a quantitative technique, thus making it an efficient and reliable tool to study geological processes at various scales (e.g. from microstructure analysis to large scale tectonic processes) [Koyi, 1997]. According to Hubbert [1937] an analogue model is a good representative of a natural prototype, if it follows the three aspects of similarity: geometric, kinematic and dynamic. Since Hubbert [1937] several other papers have been published on scaling of analogue models applied to geological processes [Hubbert, 1951; Horsfield, 1977; Shemenda, 1983; Richard, 1991; Davy and cobbold, 1991, Cobbold and Jackson, 1992].

Another major step forward in analogue modelling, especially for modelling of large-scale tectonic processes, came in the 1980’s, when realistic models were build to simulate crustal and lithospheric scale processes [Faugere and Brun, 1984; Davy and Cobbold, 1988]. Here, different types of material (brittle and viscous) were combined in one model to simulate a rheologically stratified crust and mantle, e.g. conform to the predicted strength profiles for the Earth’s crust and lithospheric mantle [Davy and Cobbold, 1988, 1991]. In these experiments, the materials were chosen as such, that the experiments were properly scaled when executed in the normal field of gravity. However, one limitation of such models is that they are unable to take into account the rheological modifications due to temperature variations during crustal or lithospheric scale deformation [Brun, 1999], such as occur during subduction and rifting. Some attempts have been made to find appropriate analogue materials to be used in thermomechanical modelling [Cobbold and Jackson, 1992; Rossetti et al., 1999] and has, for instance, proven to be useful in modelling the thermomechanical development of orogenic wedges [Rossetti et al., 2000]. In this special issue of the Journal of the Virtual Explorer, two papers are presented which also deal with thermomechanical analogue modelling of geological processes.