Middle Pleistocene

system	series	step	≈  age  ( mya )
quaternary	Holocene	Meghalayum	0 ⬍ 0.012
		Northgrippium
		Greenlandium
	Pleistocene	Young Pleistocene (Tarantium)	0.012 ⬍ 0.126
		Middle Pleistocene (Ionian)	0.126 ⬍ 0.781
		Calabrium	0.781 ⬍ 1.806
		Gelasium	1,806 ⬍ 2,588
deeper	deeper	deeper	older

The Middle Pleistocene (also Middle Pleistocene, or unofficial level Ionium) is a section of the geological epoch of the Pleistocene . It began around 781,000 (± 50,000) years ago and ended around 127,000 / 126,000 years ago with the beginning of the Young Pleistocene .

Naming

At the annual meeting of the International Union of Geological Sciences in 2020, the participants agreed to call the layer “Chibanium”. This was applied for by Japan, as the eponymous prefecture of Chiba is located here .

It is also proposed to designate the Middle Pleistocene as "Ionium" (after the Ionian Sea, where the layers of this stage were examined in detail).

definition

The lower limit of the Middle Pleistocene is defined by the Brunhes-Matuyama reversal of the earth's magnetic field.

The upper limit is defined with the base of the Eem warm period , which also corresponds to the base of the marine isotope level 5e. A Global Stratotype Section and Point ( GSSP ; corresponds roughly to a type profile) has not yet been defined for this. The proposed GSSP was the drilling in Amsterdam Airport (Eem warm period on Drenthe - ground moraine , dating approx. 127,000 before today) and, as a supplementary stratotype, the Gröbern open-cast mine (Saxony-Anhalt), where an Eem- Basin facies lies directly on the Drenthe ground moraine.

Time division

• Cromer Complex (a sequence of presumably three cold ages and intervening warm periods; from 850,000 to 475,000 years ago), duration: around 375,000 years, beginning in the Lower Pleistocene
• Elster Ice Age , corresponding to the Mindel Ice Age of the Alps (from 475,000 to 370,000 years ago), duration: around 105,000 years
• Holstein Warm Period (from 370,000 to 347,000 years ago), duration: around 23,000 years
• Saale glaciation , corresponding to the Riss glaciation of the Alps (around 347,000 to 128,000 years before today), duration: around 219,000 years

literature

• Felix Gradstein, Jim Ogg, Jim & Alan Smith: A Geologic timescale. Cambridge University Press 2005, ISBN 978-0-521-78673-7 .
• Wighart von Koenigswald: Living Ice Age. Climate and fauna in transition. Theiss-Verlag, 2002, ISBN 3-8062-1734-3 .
• Maria Bianca Cita, Luca Capraro, Neri Ciaranfi, Enrico Di Stefano, Maria Marino, Domenico Rio, Rodolfo Sprovieri and Gian Battista Vai: Calabrian and Ionian: A proposal for the definition of Mediterranean stages for the Lower and Middle Pleistocene. Episodes, 29 (2): 107-114, Beijing 2006.

Web links

• German Stratigraphic Commission (Ed.): Stratigraphische Tisch von Deutschland 2002 . Potsdam 2002, ISBN 3-00-010197-7 ( Online [PDF; 6.6 MB ; accessed on December 29, 2016]).
• Commission for the paleontological and stratigraphic research of Austria of the Austrian Academy of Sciences (ed.): The Stratigraphic Table of Austria (sedimentary layer sequences) - PDF (large)
• International Chronostratigraphic Chart 2012 (PDF)

Individual evidence

1. ↑ Researchers give geological ages a new name. Spiegel-Online, February 19, 2020, accessed on February 19, 2020 . 
2. ↑ Japanese researchers propose 'Chibanian' as name for new geologic age . In: The Japan Times Online . June 7, 2017, ISSN  0447-5763 ( japantimes.co.jp [accessed June 8, 2017]).
3. ↑ Maria Bianca Cita, Luca Capraro, Neri Ciaranfi, Enrico Di Stefano, Maria Marino, Domenico Rio, Rodolfo Sprovieri and Gian Battista Vai: Calabrian and Ionian: A proposal for the definition of Mediterranean stages for the Lower and Middle Pleistocene. Episodes, 29 (2) pp. 107-114, Beijing 2006.
4. ↑ First explanations of this are published in Episodes Vol. 31 (2) ( [1] ).