[EN] The extensional process affecting Iberia during the Triassic and Jurassic times change from the end of the Cretaceous and, throughout the Palaeocene, the displacement between the African and European plates was clearly convergent and part of the future Intern al Zone of the Betic Cordillera was affected. To the west, the Atlantic continued to open as a passive margin and, to the north, no significant deformation occurred. During the Eocene, the entire Iberian plate was subjected to compression, which caused major deformations in the Pyrenees and also in the Alpujarride and Nevado-Filabride, Internal Betic, complexes. In the Oligocene continued this situation, but in addition, the new extensional process occurring in the western Mediterranean area, togethcr with the constant eastward drift of lberia due to Atlantic opening, compressed the eastern sector of lberia, giving rise to the structuring of the Iberian Cordillera. The Neogene was the time when the Betic Cordillera reached its fundamental features with the westward displacement of the Betic-Rif lntemal Zone, expelled by the progressive opening of the Algerian Basin, opening prolonged till the Alboran Sea. From the Late Miocene onwards, all Iberia was affected by a N-S to NNW-SSE compression, combined in many points by a near perpendicular extension. Specially in eastern and southern Iberia a radial extension superposed these compression and extension.

[PO] O processo de extensâo que afectou a Ibéria durante o Triásico e Jurássico alterou-se a partir do final do Cretácico. Ao longo do Paleocénico, o deslocamento entre as placas africana e europeia foi claramente convergente, tendo sido afectada parte da futura zona interna da Cordilheira bética. A Oeste, o Atlântico continuo a abrir como uma margem passiva e, para Norte, nâo houve deformaçâo significativa. No Eocénico, a placa ibérica foi submetida a compressâo que originou deformaçcôeses nos Pirineus e nas zonas béticas internas das Alpujarridas e Nevado-Filabridas. Esta situaçâo manteve-se no Oligocénico; todavia, no Mediterráneo ocidental houve novos processos distensivos que,juntamente con a deriva para Este da Ibéria devido á abertura do Atlântico, originou compressòes no sector Este conduzindo á estruturaçâo da Cordilheira ibérica. No Neogénico, a Cordilheira belica adquiriu as características essenciais, con deslocamento para Oeste da zona interna bético-rifenha, progressivamente segregada pela abertura da Bacia argelina que se estendeu ate o mar de Alboran. A partir do Miocénico superior, a Iberia foi submetida a compressâo N-S a NNW-SSE, com extensào quase perpendicular; no Este e Sul, alëm desta compressâo, houve distensâo radial.

This paper is a contribution of thc project PB97-1267-C03 (DGESIC) and Working Group RNM-0217 (Junta de Andalucía).

15 páginas, 9 figuras.-- Trabajo presentado en el 1º Congresso sobre o Cenozóico de Portugal.

Peer reviewed