Modelling the middle pleistocene uplift in the Ardennes-Rhenish Massif: thermo-mechanical weakening under the Eifel?

Middle Pleistocene uplift in the Eifel has been interpreted as the isostatic response of the lithosphere to a deep buoyant hot body. The spatial and temporal distribution of the uplift in the Ardennes-Rhenish Massif Region has recently been constrained by new data of river incision that have been compiled in this work. The uplift distribution can be reproduced using a thin elastic plate model and assuming that the uplift is created by a deep buoyant load, the distribution of which coincides with the weakening. Models incorporating a lithospheric weakening provide a better fit of the observed uplift than models with homogeneous flexural rigidity. These results are confirmed by numerical experiments using a depth-dependent elasto-plastic plate theology, linking the flexural model with the thermo-mechanical structure of the lithosphere. (C) 2000 Elsevier Science B.V. All rights reserved.