8 research outputs found
Description and interpretation of evaporitic lithofacies ofArtesa de Segre (Upper Eocene of NE Ebre Basin)
The evaporitic sequence of Artesa de Segre (Lleida) is related to the Noguera lacustrine system (Barbastro Fm, upper Eocene to Iower Oligocene). The evaporites are found in between continental paelogene sediments. Two main gypsum levels, separated by red shales, can be distinguished. Nodulose lithofacies are predominant, showing chicken wire structures and enterolitic belts. Selenithic and laminated facies are less abundants.
The environmental context is assimilated to an alluvial fanlutitic plain-saline ephimeral /ake complex. Evaporitic percipitation and facies distribution is close related to base level changes, conditioning the thickness of water sheet, and to terrigenous suppl
El complejo deltaico de Sant Llorenç del Munt (Eoceno del borde suroriental de la depresión del Ebro)
St. Llorenç del Munt fan delta is situated in the Northeast of the Ebre basin. Three main stratigraphic units, equivalent to depositional sequences are distinguished and plotted in figure 2. In proximal fan delta areas these units are separated by erosive unconformities. In distal areas carbonate platforms which represent a maximum highstand sea level, exist between them. Sedimentary instabilities which have an effect moreover on delta front and upper prodelta, have been found in Middle Fan delta uni
The Ilerdian deposits in the Serra D'Aubens (Segre valley) and their correlation with the Ager Valley (Prov. Lleida)
The Paleogene deposits in the Serra d'Aubens (Segre valley) provide the eastermost outcrop of the assymetrical Ager sincline. Based on sedimentological and biostratigraphic analyses, four Ilerdian depositional sequences are distinguished. Compared with age-equivalent deposits of the Ager Valley, the two uppermost sequences (Ager and Llimiana, corresponding to the Baronia System) have a reduced thichness. As in the Ager Valley, these deposits consit of estuarine mixed carbonate-siliciclastic facie