Linking the northern Alps with their foreland: The latest exhumation history resolved by low-temperature thermochronology

The evolution of the Central Alpine deformation front (Subalpine Molasse) and its undeformed foreland is recently debated because of their role for deciphering the late orogenic evolution of the Alps. Its latest exhumation history is poorly understood due to the lack of late Miocene to Pliocene sediments. We constrain the late Miocene to Pliocene history of this transitional zone with apatite fission track and (U-Th)/He data. We used laser ablation inductively coupled mass spectrometry for apatite fission track dating and compare this method with previously published and unpublished external detector method fission track data. Two investigated sections across tectonic slices show that the Subalpine Molasse was tectonically active after the onset of folding of the Jura Mountains. This is much younger than hitherto assumed. Thrusting occurred at 10, 8, 6–5 Ma and potentially thereafter. This is contemporaneous with reported exhumation of the External Crystalline Massifs in the central Alps. The Jura Mountains and the Subalpine Molasse used the same detachments as the External Crystalline Massifs and are therefore kinematically coupled. Estimates on the amount of shortening and thrust displacement corroborate this idea. We argue that the tectonic signal is related to active shortening during the late stage of orogenesis

Nudel and FAK as Antagonizing Strength Modulators of Nascent Adhesions through Paxillin

Competition for binding to the cellular protein paxillin by the proteins Nudel and focal adhesion kinase is important for the proper regulation of cell adhesion and migration

Pro- vs. retro-foreland basins

Alpine-type mountain belts formed by continental collision are characterised by a strong cross-sectional asymmetry driven by the dominant underthrusting of one plate beneath the other. Such mountain belts are £anked on either side by two peripheral foreland basins, one over the underthrust plate and one over the over-riding plate; these have been termed pro- and retro-foreland basins, respectively. Numerical modelling that incorporates suitable tectonic boundary conditions, and models orogenesis from growth to a steady-state form (i.e. where accretionary in£ux equals erosional out£ux), predicts contrasting basin development to these two end-member basin types. Pro-foreland basins are characterised by: (1)Accelerating tectonic subsidence driven primarily by the translation of the basin ¢ll towards the mountain belt at the convergence rate. (2) Stratigraphic onlap onto the cratonic margin at a rate at least equal to the plate convergence rate. (3) A basin in¢ll that records the most recent development of the mountain belt with a preserved interval determined by the width of the basin divided by the convergence rate. In contrast, retro-foreland basins are relatively stable, are not translated into the mountain belt once steady-state is achieved, and are consequently characterised by: (1) A constant tectonic subsidence rate during growth of the thrustwedge, with zero tectonic subsidence during the steady-state phase (i.e. ongoing accretion-erosion, but constant load). (2)Relatively little stratigraphic onlap driven only by the growth of the retro-wedge. (3)Abasin ¢ll that records the entire growth phase of the mountain belt, but only a condensed representation of steady-state conditions. Examples of pro-foreland basins include the Appalachian foredeep, the west Taiwan foreland basin, theNorthAlpine ForelandBasin and the EbroBasin (southern Pyrenees). Examples of retro-foreland basins include the SouthWestlandBasin (SouthernAlps,NewZealand), theAquitaine Basin (northern Pyrenees), and the Po Basin (southern European Alps).We discuss how this new insight into the variability of collisional foreland basins can be used to better interpret mountain belt evolution and the hydrocarbon potential of these basins types