Palaeoenvironments and Quaternary foraminifera in the Elx coastal lagoon (Alicante, Spain)

摘要

During the Quaternary, different palaeoenvironments characterised the Elx coastal lagoon ('Albufera d'Elx') located in the easternmost sector of the Betic Ranges (SE Spain). Micropalaeontological and sedimentological analysis of three drilled cores allowed characterization of different sedimentary environments, including alluvial, restricted lagoon, lagoon with marine connection, shoreface, foreshore, backshore, swamp, washover fan, and back-barrier flat. A model of the evolution of this region during Marine Isotope Stage (MIS) 7 is proposed, based on chronostratigraphic correlation between the cores. Up to six transgressive episodes can be recognised, mostly represented by calcareous sandstones deposited in different sub-environments of the littoral zone. Holocene shoreface beds comprise unconsolidated sands. The occurrence of planktonic foraminifera at depths than 18 m indicates the existence of Pliocene marine beds beneath the Quaternary deposits. The data demonstrate that coastal lagoon systems have existed in this area of SE Spain since to at least the Middle Pleistocene.