Depósitos continentales del Eoceno superior del sector oriental de la cuenca del Ebro

• M. Fàbrega ^[1] ; E. Maestro ^[1] ; E. Parra ^[1]
  1. [1] Universitat Autònoma de Barcelona

     Universitat Autònoma de Barcelona

     Barcelona, España

     
• Localización: Geotemas (Madrid), ISSN 1576-5172, Nº. 2, 2000 (Ejemplar dedicado a: IV Congreso del Grupo Español del Terciario (Tremp, 19-21 septiembre, 2000)), págs. 67-72
• Idioma: español
• Enlaces
  • Texto Completo Ejemplar
• Resumen

  • The hinterland deposits studied are located in the eastermost area of the Catalan Central Depression (in the eastern Ebro Basin). These deposits infill an endorreic depositional basin, that was active from the uppermost Priabonian (Late Eocene) to the lower Stampian (Early Oligocene). This basin was related to Pyrenean tectonics at the N (Sta. Maria d'Olö anticline) ant to the Catalan Coastal Ranges tectonics at the S. These structural units conditioned the sedimentation and the paleotopography of the depositional furrow. During this time, the basin evolutioned from a fluvio-alluvial stage, with deposits coming from a southern source area, to a lacustrine stage, with the sedimentation of the later deposits of the basin in the western area. In the eastern area, and posteriorly to the lacustrine stage, the sedimentation continues, and consists of fluvio-alluvial deposits coming from a NW source area. These deposits can be divided in four stratigraphic informal units: Artes fluvio-alluvial unit (Ul), Avinyö deep lacustrine unit (U2), Moiä shallow lacustrine unit (U3) and Estany fluvial unit (U4). The analysis of these hinterland deposits has showed two facts related to cyclicity. By one hand, a very marked cyclicity in the stacking patterns of the different associations of exposed sedimentary bodies, and by another, a cyclicity that repeats in all orders of cycles, related to cyclic variations of the base level of the basin. The major order cycles can be related to tectonism of Catalan Coastal Ranges and Pyrenees, that influence the climate of the basin, and the minor order cycles can be related to orbital cycles, or climatic changes.