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regional tectono-geomorphic analysis indicates a Pliocene to recent rock uplift of the outermost segment of the Jura fold-and-thrust belt, which spatially coincides with the intra-continental Rhine-Bresse Transfer Zone. Elevated remnants of the partly eroded Middle Pliocene Sundgau-Forêt de Chaux Gravels identified by heavy mineral analyses allow for a paleo-topographic reconstruction that yields minimum regional Latest Pliocene to recent rock uplift rates of 0.05 ± 0.02 mm/year. This uplift also affected the Pleistocene evolution of the Ognon and Doubs drainage basins and is interpreted as being tectonically controlled. While the Ognon River was deflected from the uplifted region the Doubs deeply incised into it. Focused incision of the Doubs possibly sustained ongoing deformation along anticlines which were initiated during the Neogene evolution of the thin-skinned Jura fold-and-thrust belt. At present, this erosion-related active deformation is taking place synchronously with thick-skinned tectonics, controlling the inversion of the Rhine-Bresse Transfer Zone. This suggests local decoupling between seismogenic basement faulting and erosion-related deformation of the Mesozoic cover sequences. [ABSTRACT FROM AUTHOR]

Terra Nova, 00, 1–8, 2010 The present tectonic activity of the Jura fold-and-thrust belt is a matter of scientific debate. At its north-western front, differentially uplifted palaeo-meanders of the Doubs River record Late Quaternary growth of the Citadelle Anticline, associated with a minimum rock uplift of 13 m. Local rock uplift rates estimated from optical stimulated luminescence dating of oxbow lake deposits measure 0.17 ± 0.05 mm per annum. Reconstruction of the deformation history reveals that buckling took place simultaneously with focused Pleistocene river incision. The structural, geomorphic and temporal setting suggests that active deformation could possibly be sustained by incision-related erosion. These observations shed new light on the modes of recent deformation in the Jura Mountains and on the present-day dynamics of the Alpine orogenic front. [ABSTRACT FROM AUTHOR]