Coupling Tectonics and Surface Processes in Fold and Thrust Belts - Insights from 30 Years of Analog Modeling

Abstract

Through a rapid overview of 30 years of analog modeling studies, we outline the role of the primary mechanisms and processes that exert a strong control on fold and thrust belts evolution. Following this general approach, we address major open questions regarding the global and local responses (i.e., at orogenic scale and at the scale of faults or ridges) of a fold and thrust belt under the impact of tectonic or climatic forcing at different time scales. Insights from analog models are used to: a) characterize the behavior of wedges subject to different geometric, kinematic and rheologic boundary conditions and b) show how the interactions between surface and tectonic processes influence the structures, kinematics of deformation, exhumation mechanisms, and long-term evolution. Impact of first order parameters such as the initial tectonic setting, material transfer in the wedge, structural inheritance (OCT and inherited extensional structures), and their role on the tectonic evolution of fold and thrust belts will be successively reviewed. Several case studies of active or fossil orogens (Taiwan, the western Alps and the Variscan belt) representative of first order tectonic processes are presented in the light of field observation and analog experiments comparison.