Paleoenvironment of the Messinian Mediterranean "Lago Mare" from strontium and magnesium in ostracode shells

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doi: 10.2307/3514664
Author(s): De Deckker, Patrick; Chivas, Allan R.; Shelley, J. Michael G.
Author Affiliation(s): Primary:
Monash Univ., Dep. Geogr., Clayton, Victoria, Australia
Other:
Aust. Natl. Univ., Australia
Volume Title: Palaios
Source: Palaios, 3(3), p.352-358. Publisher: Society of Economic Paleontologists and Mineralogists, Tulsa, OK, United States. ISSN: 0883-1351
Note: In English. 30 refs.; illus. incl. sketch map
Summary: Ostracodes from Deep Sea Drilling Project (DSDP) site 376 (Florence Rise, Levantine Basin) in the eastern Mediterranean have been studied to elucidate the environments of the "Lago Mare" during the Messinian (Late Miocene). Additional ostracode samples from the Lago Mare from DSDP site 372 (East Menorca Rise, Balearic Basin) in the western Mediterranean, and from outcrops in the Sorbas Basin in southeastern Spain, the Polemi Basin in Cyprus, and from the Sitia-Lithinais Basin in Crete, were also studied. All samples contained valves of the euryhaline ostracode genus Cyprideis for which the distribution coefficient KD for Sr and Mg is known from analyses of modern specimens grown in the laboratory and from modern field collections. Because the Sr/Ca of ostracode shells is controlled by the Sr/Ca of the host water, and because the Mg/Ca of the shells is controlled both by the Mg/Ca of the water and by water temperature, Ca, Sr, and Mg analyses of individual fossil Cyprideis shells from the Lago Mare indicate the environment in which they lived. Throughout the sequence at DSDP site 376, the water was fresh or close to fresh, except for layers just above the uppermost gypsum layers, at the base of the sequence where water with some marine affinity is recognized. Above these layers, the "continental" aspect of the Lago Mare water is indisputable. Chemical analyses of single ostracode shells from site 376 and the other sites mentioned above indicate that at no time during the life of the Cyprideis ostracodes was the Lago Mare connected to the ocean. Furthermore, there is no indication that the individual basins of the Mediterranean studied here were in direct connection to one another.
Year of Publication: 1988
Research Program: DSDP Deep Sea Drilling Project
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Alkaline earth metals; Arthropoda; Biostratigraphy; Cenozoic; Crustacea; DSDP Site 372; DSDP Site 376; Deep Sea Drilling Project; Environment; Invertebrata; Leg 13; Leg 42A; Magnesium; Mandibulata; Marine environment; Mediterranean Sea; Messinian; Metals; Microfossils; Miocene; Neogene; Ostracoda; Paleoenvironment; Sedimentation; Shells; Stratigraphy; Strontium; Tertiary; Upper Miocene
Coordinates: N400152 N400154 E0044747 E0044747
N345219 N345220 E0314828 E0314826
N320000 N410000 E0290000 W0120000
Record ID: 1989016899
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by SEPM (Society for Sedimentary Geology), Tulsa, OK, United States