Pyrenees and Ebro Basin Complex

Abstract

In the Iberian Peninsula, there are two cordilleras that can be considered as part of the Alpine system: the Pyrenees and the Baetic Cordillera. The latter, although it possesses peculiarities that make it different from other Alpine chains, as in the development and the position of preorogenic vulcanism and, to a certain extent, in the characteristics of its thrust nappes, compares well with the general style of these chains. Its complicated structure in terms of thrust nappes and the metamorphism affecting its internal zones is matched in the other Alpine systems. The Guadalquivir depression, which constitutes a foredeep, is related intimately to the Baetic Cordillera and contains materials entering as thrust nappes. On the other hand, the Pyrenees are a much more special type of fold mountain system, not so much because of their evolution but because of their structure, dimensions and position. The bilateral structure, with a Palaeozoic axial zone bordered by two folded systems of opposite direction, makes this cordillera one of moderate width, contrasting with the structure of other cordilleras, such as the Alps and the Carpathians.