The geometric and kinematic evolution of the south Urals foreland thrust and fold belt appears to have been quite simple. Despite this simplicity, there are several key differences when compared with foreland thrust and fold belts developed in other orogens, in particular the anomalously small amount of shortening (14 %), and the location and geometry of the basal thrust in the basement. To understand the possible reasons that led to its evolution, the critical wedge model was applied to try and determine the relative contribution of the mechanical factors that acted on the wedge during its development. The south Urals foreland thrust and fold belt appears to be a 'snapshot' of a developing wedge that is preserved in the subcritical field.
In recent years significant advances have been made in the understanding of the geometric, kinematic, and mechanical development of foreland thrust and fold belts. These advances have largely come about due to the development of section balancing techniques (e.g. Dahlstrom 1969; Hossack 1979), kinematic modelling (e.g. Geiser 1988), and critical wedge modelling (Davis et al. 1983; Dahlen et al. 1984). Whether applied individually or together these techniques are powerful tools for investigating the frontal parts of orogenic belts. They have demonstrated that a number of general features are found in many of the worlds foreland thrust and fold belts (e.g. Rodgers 1990) that reflect their mechanical development, although there are many notable exceptions (e.g. Rodgers 1991). Section balancing and kinematic modelling have shown that foreland thrust and fold belts