Revistes Catalanes amb Accés Obert (RACO)

Análisis estratigráfico del Paleógeno del sinclinal de Tragó de Noguera: su importancia en la geología regional (Pirineo catalano-aragonés, España)

J. Ullastre, A. Masriera

Resum


The discovery in the Tragó de Noguera syncline of eleven Charophyte outcrops in succession from Maastrichtian to Oligocene times gives us a deeper insight into the chronostratigraphic evolution of the Sierras marginales of the central unit of the southern Pyrenees. The interference between tectonics and sedimentation is a continuous process during this long period of time (about 40 m.y.). In fact, the tectonic phases of Maastrichtian, Paleocene and Lower Eocene, to date only know in the north part of the South-Pyrenean Central Unit, have been found by us in the south border. We also show their continuity during the Upper Eocene and Oligocene. These evidences are incompatibles with a model of tectonic movements in sequence affecting for parts the South-Pyrenean Unit.
Knowledge of the sedimentary relationships between the foreland Ebro basin and the southern border of the Pyrenees from Upper Eocene is considerably improved. We conclude again, that the evaporitic paleogene sedimentation came about simultaneously and indistinctly over the foreland and the border of the South-Pyrenean Central Unit.

Key words: Pyrenees, Spain, Charophytes, Maastrichtian, Paleogene, Paleogeography, Tectonics.

Text complet: PDF