Facies Architecture of the Llobregat River Quaternary Deltas, Barcelona, Spain

摘要

The Llobregat River has accumulated multiple deltas through Quaternary eustatic cycles. The rapid risesand step-wise, relatively slower falls in sea level have produced a bias towards preserving forced regressivesystem tracks and eroding the high-stand system tracks with the exception of the Holocene delta. Subsurfacedata indicates that the Quaternary deltas were feed by the Llobregat river and «rieras» derived from Garrafand Collserola, but the sediment was probably redistributed by long-shore currents to form a unique deltafront. The Holocene Llobregat River high-stand delta progrades over older fluvial, flood-plain and shorelinedeposits equivalent to the older deltas now preserved at the continental margin. A number of paleo-flowchannels feeding the older Quaternary deltas illustrate the complexity for the exploitation and protectionof groundwater found in these deposits