Lago Mare and the Messinian Salinity Crisis: Evidence from the Alboran Sea (S. Spain)

Abstract

International audienceThis paper provides a new environmental, sedimentological and stratigraphic context of the Lago Mare deposits from the North Alboran region and clarifies their chronologic location with respect to the Messinian Salinity Crisis. We present new micropaleontological data (dinoflagellate cysts, calcareous nannoplankton, planktonic foraminifers), correlated with field observations and offshore seismic interpretations. We show that the Lago Mare event known in three onshore localities (Río Mendelín near Malaga, Zorreras near Sorbas, Gafares near Níjar) follows the marine reflooding of the Mediterranean Basin which ended the Messinian Salinity Crisis. Chronologically, these Lago Mare deposits last from the latest Messinian to the early Zanclean. In fact, the first influx of Paratethyan- organisms is revealed by the dinoflagellate cyst record from near Malaga within a Gilbert-type fan delta overlying the Messinian Erosional Surface. Invading molluscs and/or ostracods may have persisted in lagoonal coastal areas more or less affected by discontinuous marine influxes (Sorbas and Níjar). The Malaga area is convenient for a paleogeographic and sedimentary reconstruction which shows the prevalent forcing of sea level changes during the time-interval 5.600-5.332 Ma at the difference of the usually solicited prevalent tectonics. The studied Lago Mare event is the third episode resulting in such a paleobiological assemblage in the Mediterranean region and corresponds to the final two-way water exchange at high sea level between the Mediterranean and the former Paratethys. It documents the onset of the modern marine circulation in the Mediterranean after the reflooding ending the Messinian Salinity Crisis

Late Messinian mollusks and vertebrates from Moncucco Torinese, north-western Italy. Paleoecological and paleoclimatological implications

“…Modified from Lozar et al (2015). 4 ated with the so-called Lago-Mare event, when the Mediterranean experienced cyclic water salinity variations and is believed to have progressively established a stable connection with the Atlantic Ocean (CIESM, 2008;Cita et al, 1978;McCulloch and De Deckker, 1989;Carnevale et al, 2006aCarnevale et al, , 2006bDo Couto et al, 2014). The fossiliferous layers of MCC are located at the top of a gypsum quarry.…”

A gastropod-based biogeographic scheme for the European Neogene freshwater systems

“…During the Late Messinian, the Proto-Mediterranean Sea is strongly restricted as a result of a hydrological cut-off from the Atlantic Ocean resulting in widespread evaporite precipitation and a decrease in Mediterranean sea level (Messinian Salinity Crisis; Krijgsman et al, 1999;Popov et al, 2006;Krijgsman et al, 2010;Garcia-Castellanos and Villaseñor, 2011). The successive freshwater-brackish to marine deposits are commonly referred to as 'Lago-mare' as coined by Ruggieri (1962) and have been reported from the entire Mediterranean basin (Cipollari et al, 1999;Esu, 2005;Carnevale et al, 2006;Esu, 2007;Carnevale et al, 2008;Guerra-Merchán et al, 2010;Do Couto et al, 2014). The gastropod assemblages reported from these deposits are characterised by throughout similar compositions and together constitute a well-defined biogeographic region.…”

The Roussillon Basin (S. France): A case-study to distinguish local and regional events between 6 and 3 Ma

“…Its dip is sometimes steep but not everywhere, especially where the aggrading continental Pliocene may be conformable over the older rocks. In such a situation, the contact is not an angular unconformity but only a chronostratigraphic gap and the label MES should be replaced by "Messinian Discontinuity" (for details and examples, see: Melinte-Dobrinescu et al, 2009;Do Couto et al, 2014;Clauzon et al, 2015). These features lead us to believe that the future representation of the MES will be a three-dimensional interpolation based on field surveys, seismic profiles and well sections.…”