Revistes Catalanes amb Accés Obert (RACO)

El Mesozoico de Artesa de Segre: precisiones estratigráficas y análisis tectónico-sedimentario del 'frente' sudpirenaico entre Artesa y Camarasa (Pirineo catalán, España)

J. Ullastre, A. Masriera

Resum


The know mesozoic outcrops of Artesa de Segre at the southeastern limit of the South-Pyrenean Central Unit (Catalonian Pyrenees) is the object of: 1st, stratigraphical precisions; 2nd, some tectonic and sedimentary considerations which are the origin of a more extensive analysis. In this, are treated the space-temporal relationship of structural sedimentary order between the southern border of the South-Pyrenean Central Unit and the Tertiary of the foreland basin (Catalan Central Basin).
We intend to interpret correctly the different sedimentary episodes (detrital and evaporitic) of the foreland basin establishing their succession, dating them by Charophytes and following their cartography from the border of the Catalan Central Basin to above the South-Pyrenean Units.
As a result we have: 1st. that the ocurrence of this south-pyrenean border must have taken place during the evaporitic sedimentation of the Upper Eocene; 2nd, that the post 'nappe' sedimentation (Uppermost Eocene-Oligocene) is slightly conglomeratic at first, later evaporitic and finally once again detrital; 3rd, that the visible tectonic contacts are all younger. Finally there is a doubt whether the border studied was the true front of the South-Pyrenean Central Unit during the tangential phase of the Upper Eocene-Oligocene time.

Key words: Catalonian Pyrenees (Spain). Catalan Central Basin. South-Pyrenean front. Tectonics and sedimentation. Upper Eocene-Oligocene.

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