Procesos activos de expansión lateral en la vertiente de la Serra de Tramuntana de Mallorca

Abstract

The Tamuntana Range in Mallorca has a steep coastal slope. The arrangement of the materials on the hillsides consists of stiff masses of Mesozoic limestones above the Keuper plastic materials. Both, the erosion of streams and the marine action dismantle the upper brittle unit and expose the lower plastic one, causing its lateral unconfinement. Thus, the weight of the overlying material produces vertical contraction, subsidence and lateral spreading of the underlying plastic unit. Simultaneously the brittle upper unit fractures to accommodate the plastic deformation, generting a jointed rock material with both, horzontal and vertical movement of large individual blocks. These processes are characterized by very slow rates of movement and they have been identified in some parts of the range giving place a characteristic landscape on the coastal fringe.