On the classification of tectonic units in the Nevado-Filabride complex of the Northern Sierra de los Filabres, Betic Cordilleras, SE Spain.

Abstract

A layer of calcareous cataclasites, formerly considered to be interstratified in permo-Mesozoic rocks in the lowest Nevado-Filabride tectonic unit - the Nevado-Lubrín unit - locally contains fragments of pre-Permian black schist. It is argued that the cataclasite represents a fault-rock formed in association with an important overthrust. This leads to a revision of the lithostratigraphy of the Nevado-Lubrín unit, with the cataclasitc forming the uppermost rock-body. The cataclasite is tectonically overlain by the Secano unit (composed of pre-Permian black schist and quartzite) and - where this unit is absent - by the Umbria de las Cantèras unit (consisting of a sequence of marble and calcschist). This latter thrust-mass was hitherto misinterpreted as the stratigraphic upper part of the Nevado-Lubrín unit. which led to a seemingly enigmatic position of the Secano-unit within the Nevado-Filabride rock-pile. The present interpretation solves this 'Secano-problem', as thrusting of the Umbria de las Canteras unit over the Secano unit is recognized.