KEYNOTE: NUMERICAL MODELING OF THE MEXICAN FOLD-AND-THRUST BELT

Geodynamic numerical models of fold-and-thrust belts indicate that the distribution of frictional heterogeneities within the crust strongly affects the kinematics and mechanical evolution of these models. In this contribution, we investigate the impact of frictional crustal heterogeneities and surface processes on the evolution of thin-skinned fold-and-thrust belts using the Gale numerical code to simulate the interpreted frictional properties of the Mexican fold-and-thrust belt (MFTB) and study its kinematic evolution and the potential effect of surface erosion. We specifically used Gale capabilities, inserting crustal units with different internal and basal friction coefficients based on lithologic descriptions and field observations and interpretations, to quantify the shortening experienced by each lithotectonic unit. The lithologic descriptions and field observations and interpretations where extracted from field data from the Toliman Sequences, El Doctor Platform, Zimapan Basin, Valles-San Luis Platform, and Tampico Misantla Basin. Our results indicate that the evolution of the MFTB requires a rheologically heterogeneous crust but only limited erosion to explain the geometries and total shortening constrained by field observations and interpretations.