Messinian
Encyclopedia
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...

. It spans the time between 7.246 ± 0.005 Ma and 5.332 ± 0.005 Ma (million years ago). It follows the Tortonian
Tortonian
The Tortonian is in the geologic timescale an age or stage of the late Miocene that spans the time between 11.608 ± 0.005 Ma and 7.246 ± 0.005 Ma . It follows the Serravallian and is followed by the Messinian....

 and is followed by the Zanclean
Zanclean
The Zanclean is the lowest stage or earliest age on the geologic time scale of the Pliocene. It spans the time between 5.332 and 3.6 Ma ± 0.005 Ma . It is preceded by the Messinian age of the Miocene epoch, and followed by the Piacenzian age....

, the first age of the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...

.

The Messinian overlaps the Turolian
Turolian
The Turolian age is a period of geologic time within the Miocene used more specifically with European Land Mammal Ages. It precedes the Ruscinian age and follows the Vallesian age. The Turolian overlaps the Tortonian and Messinian ages....

 European Land Mammal Mega Zone (more precise MN 12 and 13) and the Pontian
Pontian
Pontian may refer to:* Pontian, in stratigraphy the uppermost Miocene Paratethys stage, coeval with the Messinian* Pontian Greeks, a group of ethnic Greek who inhabited northern Turkey* Pontian Islands, a group of islands on the coast of Italy...

 Central European Paratethys
Paratethys
The Paratethys ocean, Paratethys sea or just Paratethys was a large shallow sea that stretched from the region north of the Alps over Central Europe to the Aral Sea in western Asia. The sea was formed during the Oxfordian epoch as an extension of the rift that formed the Central Atlantic Ocean and...

 stage. It also overlaps the late Huayquerian
Huayquerian
The Huayquerian age is a period of geologic time within the Miocene epoch of the Neogene used more specifically with South American Land Mammal Ages. It follows the Mayoan and precedes the Montehermosan age....

 and early Montehermosan
Montehermosan
The Montehermosan age is a period of geologic time within the Miocene epoch of the Neogene used more specifically with South American Land Mammal Ages. It follows the Huayquerian and precedes the Chapadmalalan age....

 South American Land Mammal Ages, and falls inside the more extensive Hemphillian
Hemphillian
The Hemphillian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 10,300,000 to 4,900,000 years BP, a period of . It is usually considered to overlap the Tortonian epoch of the Late...

 North American Land Mammal Age.

During the Messinian, around 6 million years ago, the Messinian salinity crisis
Messinian salinity crisis
The Messinian Salinity Crisis, also referred to as the Messinian Event, and in its latest stage as the Lago Mare event, was a geological event during which the Mediterranean Sea went into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age of the Miocene...

 took place, which brought about repeated desiccations of the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...

.

Definition

The Messinian was introduced by Swiss
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

 stratigrapher Karl Mayer-Eymar in 1867. Its name comes from the Italian
Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 city of Messina on Sicily
Sicily
Sicily is a region of Italy, and is the largest island in the Mediterranean Sea. Along with the surrounding minor islands, it constitutes an autonomous region of Italy, the Regione Autonoma Siciliana Sicily has a rich and unique culture, especially with regard to the arts, music, literature,...

, where the Messinian evaporite
Messinian evaporite
The Messinian evaporite deposit is a geological deposit of evaporites which was found on Sicily and named after the city of Messina. It was later found to underlie much of the bed of the Mediterranean. It was formed during the Messinian salinity crisis....

 deposit is of the same age.

The base of the Messinian is at the first appearance of the plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...

ic foram species Globorotalia conomiozea and is stratigraphically in the middle of magnetic chronozone C3Br.1r. The GSSP for the Messinian is located in a section at Oued Akrech, near the Moroccan
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...

 capital Rabat
Rabat
Rabat , is the capital and third largest city of the Kingdom of Morocco with a population of approximately 650,000...

.

The top of the Messinian (the base of the Zanclean stage and Pliocene series) lies with the top of magnetic chronozone Cr3 (about 100.000 years before the Thvera normal subchronozone C3n.4n). The base is also close to the extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 level of the calcareous nanoplankton species Triquetrorhabdulus rugosus (the base of biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....

 CN10b) and the first appearance of nannoplankton Ceratolithus acutus
Ceratolithus
is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Arenig stage of the Ordovician Period, approximately 478 to 471 million years ago....

.

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