Sedimentary environment and stratigraphic ciclicity of the Lower Cretaceous «Arenas y arcillas del Collado» Formation, in Alpuente (Valencia)

The «Arenas y arcillas del Collado» Formation (Lower Cretaceous, Southwestern Iberian Basin, Valencia) represent a wave-dominated delta. It contain fluvial and shallow- marine deposits wich are arranged in two types of high-frequency sequences. The first type (up to 2 m thick) is a transgressive - regressive parasequence formed by shoreface to fluvial deposits. The second type (up to 15 m thick) is a composite depositional sequence formed by four to six parasequences. The lower part of each deoositional sequence contain a progradational thick group of shoreface / foreshore sandstone units, which sharply overlies an erosional surface modified by waves during transgressio