Neogene evolution of the Campo de Dalias and the surrounding offshore areas - (Northeastern Alboran Sea)

Abstract

The Campo de Dalias is an emerged portion of the Alboran Sea, located on its northeastern margin. The study of this basin and its surrounding offshore areas reveals the structure on the region, whose outstanding feature is the N70-80E anticline extending from Guardias Viejas to Roquetas and continuing eastward under the sea. The other parts of the structure are characterized by several fault sets, the most important of which are those of N 70-9OE, N 120E and N45E direction. Some of these fault sets of originally different ages later replayed throughout the late Miocene up to the Quaternary. These replays seem to have occurred in approximately N-S compressive situations.The main compressive events took place in the latest Torto-nian and early Pleistocene. Between these two events a stage of considerable subsidence in the Pliocene basin can be detected, which caused the accumulation of sediments over a thousand metres thick in some places. Equally, we can detect an important uplift of the surrounding reliefs coeval with subsidence. Two transgressive situations are recorded and two important eustatic falls and partial emersion of the basin margin, mainly during the Messinian.