Regional implications of a Palaeozoic age for the Nevado-Filabride Cover of the Betic Cordillera, Spain

The Rb/Sr whole-rock age of granitoid gneiss interlayered with marbles at t he top of the Nevado-Filabride Complex cover is 247 +/- 11 Ma (Permian-Tria ssic boundary). Tourmaline-rich metasediments were metasomatized by B-rich fluids from the igneous body. Hence the igneous rocks were emplaced in the sedimentary rocks that now host the gneiss body, precluding a later tectoni c emplacement. Therefore, the entire Nevado-Filabride Complex is Palaeozoic or older and may have been the stratigraphic basement of the immediately o verlying Alpujarride units, which include younger rocks. The consistent evo lution of the Alpine high-pressure metamorphism in the: Nevado-Filabride an d Alpujarride complexes might therefore be due to their original stratigrap hic relationship.