Characteristics of collisional orogens with low topographic build-up : an example from the Carpathians

Sequence stratigraphy in the hinterland, kinematic analysis of thin-skinned thrusting in the foreland and thermochronological tracking of exhumation in the orogenic core are combined to quantify the mechanics of an orogen with low topographic build-up. The Carpathian system demonstrates that collisional deformation can couple and thicken the lower orogenic plate along reverse faults that dip more steeply than the subduction zone, defining a foreland-coupling type of collision. Near the surface, this is expressed by wide antiforms in the upper plate and the thin-skinned orogenic wedge. A sequence stratigraphic analysis of the back-arc Transylvanian Basin demonstrates that the sedimentary architecture records orogenic uplift pulses with both short and long wavelengths. These correspond to the activation of individual thrust sheets in the thin-skinned wedge and to lower-plate coupling events respectively.