The end of the Messinian Salinity Crisis in the western Mediterranean: insights from the carbonate platforms of south-eastern Spain. - Université Pierre et Marie Curie Accéder directement au contenu
Article Dans Une Revue Sedimentary Geology Année : 2010

The end of the Messinian Salinity Crisis in the western Mediterranean: insights from the carbonate platforms of south-eastern Spain.

Résumé

How the Messinian Salinity Crisis (MSC) ended is still a matter of intense debate. The Terminal Carbonate Complex (TCC) is a late Messinian carbonate platform system that recorded western Mediterranean hydrological changes from the final stages of evaporite deposition till the advent of Lago-Mare fresh- to brackish water conditions at the very end of Messinian times. A multidisciplinary study has been carried out in three localities in south-eastern Spain to reconstruct the history of TCC platforms and elucidate their significance in the MSC. Overall, this study provides evidence that the TCC formed following a regional 4th order water level rise and fall concomitant with an opening-restriction trend. It can be subdivided into four 5th order depositional sequences (DS1 to DS4) recording two phases: (1) from DS1 to DS3, a tide-dominated ooidic to oobioclastic system with stenohaline faunas developed as a result of a 70 m water level rise. During this period, the TCC developed in a shallow sea with close to normal marine salinity; (2) in depositional sequence 4, a microbialite-dominated platform system developed. This is indicative of a significant environmental change and is attributed to a 30 to 40 m water level fall in the basins under study. These restricted conditions were coeval with intense evaporite deformation and brine recycling. The synsedimentary deformation of evaporites had a major impact on platform architecture and carbonate production, affecting the Messinian series throughout south-eastern Spain at the end of the TCC history. At that time, the TCC developed in a lake with fluctuating, brackish- to hypersaline water. These findings suggest a temporary restoration of marine conditions in the western Mediterranean marginal basins due to Atlantic water influxes prompted by a global sea level rise around 5.6 Ma. Whether marine conditions extended to the entire western Mediterranean still needs to be investigated.

Dates et versions

hal-00509894 , version 1 (17-08-2010)

Identifiants

Citer

Raphaël Bourillot, Emmanuelle Vennin, Jean-Marie Rouchy, Marie-Madeleine Blanc-Valleron, Antonio Caruso, et al.. The end of the Messinian Salinity Crisis in the western Mediterranean: insights from the carbonate platforms of south-eastern Spain.. Sedimentary Geology, 2010, 229 (4), pp.224-253. ⟨10.1016/j.sedgeo.2010.06.010⟩. ⟨hal-00509894⟩
146 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More