Resumen de Influencia de la geometría del "backstop" en el orógeno pirenaico: modelización analógica
R. Soto Marín, Antonio María Casas Sáinz, F. Storti
In this work, we carry out analogue experiments with a rigid backstop with wedge shape and horizontal sand cake. Backstops with along-strike thickness variations cause lateral variations in the thrust wedge: as the thickness of the backstop increases, the thickness and displacements of the thrust units and the elevation of the orogenic wedge increase, whereas backthrusts of the orogenic wedge show lower displacements. These results can be applied to the building of the Pyrenean orogen during Tertiary: the European plate could behave as the backstop for the orogen, since its thickness variations, inherited from M esozoic extension, can account tor: (i) the different elevation of the Axial Zone in the Pyrenees, diminishing from E to W and (ii) the variation in the displacement and thickness of Palaeozoic thrust units in the same direction.
