APPLICATION OF STRUCTURAL MODELS TO FOLD-THRUST BELTS – POSITIVE AND NEGATIVE OUTCOMES FOR UNDERSTANDING STRUCTURAL EVOLUTION

For a century geologists have been applying structural balancing and restoration techniques to aid in the understanding of structural geometries and their evolution. Deformation of the crust and the associated structural architecture is a key element of major surface features such as rift basins and mountain belts. These major surface features and their underlying geological roots play a key role in global systems such as climate, as well as resource formation and trapping. In applying structural kinematic models geologists recreate or restore the present day geometries to help understand their genesis and to predict other elements such as depth to detachment. In choosing which model to apply in a restoration the geologist implies the specific mechanisms of kinematic formation and evolution of the structure.

In a series of examples I consider how kinematic structural models for fold-thrust belts have been used to interpret seismic datasets. From these examples the implications for structural evolution and predictions of other elements are considered and the pitfalls and positive outcomes of their use in understanding natural systems are highlighted. The results show that such kinematic models are not ubiquitously applicable to all fold-thrust belts and they must be applied with care and understanding. However, the studies considered suggest that there are almost always clear benefits in thinking and using kinematic structural models, even if their use proves the chosen model is incorrect for the structural system analysed.