Geomorphological evidences of activity quaternary in the mountain front of the south border of Sierra Nevada. The normal fault of Laujar de Andarax

Abstract

In the sector of Laujar of Andarax, in the contact of the south border Sierra Nevada and the Alpujarran corridor, an active normal fault exists, now described for the first time in this work. This fault, with an E-W direction, generates a marked mountain front and affects to upper Pleistocene sediments. This mountain front is prolonged toward the west, but less conserved due to the fluvial erosion. By the contrary, the sector of Laujar, in the watershed of two rivers draining great part of the Alpujarran corridor (Adra and Andarax), is less affected by the fluvial erosion, conserving Quaternary piedmont deposits. This fact allowed to observe and quantify the deformations. The uplift rates of the south border of Sierra Nevada according to the vertical movements and the age of the sediments affected by the fault zone are comprise between 0,43 and 0,75mm/year.