La extraña topografía de la Península Ibérica

Abstract

Spain has a very high mean topography (2nd in Europe, after Switzerland) that demonstrates the intensity and great dispersion of the recent tectonic (Tertiary) deformations. The relief of Iberia is the result of the transmitted stresses towards the interior from the active border during the Oligocene-Lower Miocene: The Pyrenees. These deformations were organized in a highly regular way, giving place to a series of structural highs (ranges-chains) and lows (basins), which are interpreted as lithospheric scale folds. From this perspective, the whole Iberian plate turns out to be deformed during the Cenozoic. These large folds (Pyrenees-Cantabrian Mountains, Central System- Iberian Chain, Sierra Morena) turn out to be connected in upper crust by means of a series of left lateral (Vilariça, Messejana-Plasencia) and right lateral (Ventaniella, Iberian Chain) strike slip corridors, that are also important to explain the morphology of The Peninsula. The emplacement towards the west of the Alborán block mechanically decoupled this device, which only continues active on the Atlantic coast - gulf of Cadiz. It is in these structures, large folds and strike-slip corridors, where the current seismicity concentrates.