El terciario del Baix Ebre: Aportaciones estratigráficas y sedimentológicas
Abstract
Cenozoic rocks which crop out near Sant Onofre in Baix Ebre area, Tarragona, Spain, have been studied. Seven lithoestratigraphic units are diferenciated. The lowermost unit (<<Pisolitic Clay>> unit) is attributed to the Paleocene. The overlying units are Neogene in age: the <<Conglomerates of the Venta Ranxero >> unit wich is attributed to the Miocene corresponds to midle alluvial fan deposits. The <<Siliceous Conglomerates of Anguera>> unit is attributed to Late Miocene (Turolian) and records fluvial braided sedimentation. Pliocene sedimentation began with the <<Gravels and Sands with Oysters, unit. This is a transgresive unit where we can diferentiate foreshore and shoreface deposits. The <<Blue Marls of Carnpredó>> unit is attributed to shallow marine deposits. Sandstone deposited by high and medium storm density flows occur in this unit. The <<Sant Onofre Limestones>> unit corresponds to palustrine and lacustrine deposits whit expansive and retractive sequences. The uppermost unit (<<Roca Corba Conglomerates>> unit) corresponds to debris flow and braided fluvial deposites attributed to the Villafranchian.