Response of drainage systems to Neogene evolution of the Jura fold-thrust belt and Upper Rhine Graben

Abstract

The eastern Jura Mountains consist of the Jura fold-thrust belt and the autochthonous Tabular Jura and Vesoul-Montbéliard Plateau. They are drained by the river Rhine, which flows into the North Sea, and the river Doubs, which flows into the Mediterranean. The internal drainage systems of the Jura fold-thrust belt consist of rivers flowing in synclinal valleys that are linked by river segments cutting orthogonally through anticlines. The latter appear to employ parts of the antecedent Jura Nagelfluh drainage system that had developed in response to Late Burdigalian uplift of the Vosges-Back Forest Arch, prior to Late Miocene-Pliocene deformation of the Jura fold-thrust belt.

The following stages are recognized in the evolution of the Jura Mountain drainage systems: 1) middle to late Tortonian (10–7.2 Ma) folding-related overpowering and partial reversal of the south-directed Jura Nagelfluh drainage system, 2) Messinian to early Pliocene (7.2–4.2 Ma) Aare-Danube and proto-Doubs stage, 3) early to middle Pliocene (4.2–2.9 Ma) Aare-Doubs stage, 4) late Pliocene to early Quaternary (2.9–1.7 Ma) Aare-Rhine and Doubs stage and 5) Quaternary (1.7–0 Ma) Alpine-Rhine and Doubs stage.

Development of the thin-skinned Jura fold-thrust belt controlled the first three stages of this drainage system evolution, whilst the last two stages were essentially governed by the subsidence of the Upper Rhine Graben, which resumed during the late Pliocene. Late Pliocene and Quaternary deep incision of the Aare-Rhine/Alpine-Rhine and its tributaries in the Jura Mountains and Black Forest is mainly attributed to lowering of the erosional base level in the continuously subsiding Upper Rhine Graben. Incision of the Doubs and Dessoubre canyons reflects uplift of the Franches-Montagnes and Franche-Comté in response to thick-skinned deformation of the Jura fold-thrust belt, which had commenced around 3 Ma.

Geodetic data indicate that uplift of the Jura Mountains, relative to the Tabular Jura, presently continues at very low strain rates whilst the Upper Rhine Graben subsides very slowly and the Black Forest is relatively stable.