Reconstructing lake bottom water temperatures and their seasonal variability in the Dead Sea Basin during MIS5e

The Depositional Record

Daniel Ariztegui¹  Frédéric Caupin²  Véronique Gardien³  Philippe Sorrel³  Emmanuel Guillerm³  Niels S. Brall³ 

[1] Department of Earth Sciences University of Geneva Geneva Switzerland;Institut Lumière Matière Université Claude Bernard Lyon 1 CNRS Université de Lyon Lyon France;Laboratoire de Géologie de Lyon: Terre Planètes et Environnement Université Claude Bernard Lyon 1 CNRS Université de Lyon Villeurbanne France;

关键词: Brillouin spectroscopy;    Dead Sea Basin;    fluid inclusions;    marine isotope stage (MIS) 5e;    palaeotemperature;    seasonal halite facies;   

DOI  :  10.1002/dep2.185

来源: DOAJ

【 摘 要 】

Abstract Interglacial periods are characterised by thick accumulations of halite units in the Dead Sea Basin. During these intervals, small water droplets (fluid inclusions, FIs) were entrapped in the halite crystals which serve as windows to estimate the chemistry and physical properties of the primary lake water conditions. Brillouin spectroscopy is used here to reconstruct annual resolution temperatures from a halite core section in the Dead Sea Basin during the onset of Marine Isotope Stage 5e (ca 130 ka) of the Last Interglacial. Lake bottom temperatures can be inferred based on the occurrence of coarse/fine halite facies, as observed today with the formation of equivalent halite facies during winter/summer seasons in the Dead Sea. A recurring increase in lake bottom temperatures is found along the direction of coarse halite layers in three successive years. Moreover, low FI entrapment temperatures were detected in layers of fine (cumulate) halite facies. These results imply a twofold stronger seasonality in the Dead Sea Basin compared to today, with colder winters at the onset of Marine Isotope Stage 5e. The results therefore highlight the potential of using cyclic salt deposits to reconstruct seasonal temperature variability for numerous evaporitic environments in the geological record.

【 授权许可】

Unknown