Orosirium

Aeonothem	Arathem	system	Age ( mya )
later	later	later
P r o t e r o z o i k u m Duration: 1959 Ma	Neoproterozoic Jungproterozoikum Duration: 459 Ma	Ediacarium	541 ⬍ 635
		Cryogenium	635 ⬍ 720
		Tonium	720 ⬍ 1000
	Mesoproterozoic Mittelproterozoikum Duration: 600 Ma	Stenium	1000 ⬍ 1200
		Ectasium	1200 ⬍ 1400
		Calymmium	1400 ⬍ 1600
	Paleoproterozoic Altproterozoikum Duration: 900 Ma	Statherium	1600 ⬍ 1800
		Orosirium	1800 ⬍ 2050
		Rhyacium	2050 ⬍ 2300
		Siderium	2300 ⬍ 2500
earlier	earlier	earlier

The orosirian is the third geological period within the eon Proterozoikum (and within the era Paleoproterozoic ). It took 250 million years. Its beginning is radiometrically set at 2050 million years BP and its end at 1800 million years BP. It follows the period of the Rhyacium and is replaced by the Statherium .

Naming

The name is derived from the Greek ὀροσειρά - oroseira (German: mountain range ). He is alluding to the mountain building processes that were widespread in the second half of the Orosirium and that took place on practically every continent that existed at the time .

Events during the Orosirium

The remains of the Vredefort crater visible from orbit

the atmosphere

Because of the increased photosynthesis of the cyanobacteria , the oxygen content in the atmosphere in the orosirium increased further, which promoted the formation of red sediments .

evolution

Life is determined by prokaryotic protozoa in the oceans.

Mantle avalanche

According Condie (1998) should be around 1900 million years BP called a mantle Avalanche ( Engl. Mantle avalanche have occurred), which means increased Manteldiapire would explain the enormous magmatism at this time.

Meteorite crater

The formation of the Vredefort Crater in South Africa (approx. 2,023 ± 4 million years ago BP) and that of the Sudbury Basin approx. 1,849 million years ago fell into the Orosirium , each due to the impact of an asteroid .

stratigraphy

Significant sedimentary basins and geological formations

Transvaal Basin in South Africa - 2600 to 1900 million years BP
Animikie Group in the United States and Canada - 2125 to 1780 million years BP
Huronian Supergroup in Eastern Ontario - 2450 to 2219 million years BP, possibly until 1850/1800 million years BP, when the supergroup was finally captured by the Penokean orogeny
Marquette Range Supergroup in Northern Wisconsin and Michigan - 2207 to 1818 million years BP
Cuddapah Basin in south-east India (from around 1930 million years BP) with:
- Cuddapah super group consisting of:
  - Chitravati group (base at 1884 million years BP)
  - Papaghni Group (1930 to 1900 million years old BP)

Deposits

The Siberian copper deposits of Udokan are among the largest ore deposits that arose during this period .
In Minnesota , the band ores (BIF) of the Gunflint Iron Formation (1878 ± 2 million years BP), the Soudan Iron Formation and the Biwabik Iron Formation (approximately 1900 to 1850 million years BP) are deposited.

Geodynamics

Orogenesis

Continent collisions:

Maroni-Itacaiunas belt of the Amazon craton in South America - 2200 to 1950 million years BP
Transamazon orogeny in South America - 2100 to 2000 million years BP
Eburnian Orogeny in West Africa - 2100 to 2000 million years BP
Limpopo Belt in South Africa - 2000 to 1900 million years BP
Capricorn orogeny in Western Australia - 2000 to 1900 million years BP
Khondalite Belt (or Central Indian Tectonic Zone , abbreviated CITZ) in southern India - around 1950 to 1800 million years BP
Ventuari Tapajos Belt of the Amazon Craton in Brazil - 1950 to 1800 million years BP
Penokean orogeny in North America - 1900 to 1800 million years BP
Taltson-Thelon orogeny in North America - 1950 to 1830 million years BP
Trans-Hudson orogeny in North America - 1950 to 1830 million years BP
Wopmay orogeny in North America - 1950 to 1830 million years BP
Svekofennian orogeny in Scandinavia - 1900 to 1800 million years BP
Patschelma orogenesis ( aulakogen ) in Eastern Europe - 1900 to 1800 million years BP
Volhynia-Central Russia Orogeny (Aulakogen) in Eastern Europe - 1900 to 1800 million years BP
Akitkan orogeny in Siberia - 1900 to 1800 million years BP
Central Aldan orogeny in Siberia - 1900 to 1800 million years BP

In the period 1950/1900 to 1830 million years BP, terranes are accreted in the following orogenous regions :

Torngat orogen in Labrador and Quebec

New Quebec Orogen in Quebec

Ungava orogen in Quebec

Nagssugtoqidian Orogen in Greenland

Lapland Kola Orogen (also Lapland Karelia Orogen) in northern Scandinavia

Around 1870 million years BP, the Rona Terran was docked to the Gairloch Terran / Gruinard Terran in the Hebridean Terran of north-west Scotland . The supracrustal Loch Maree Group formed from 2000 million years ago onwards is amphibolite facially metamorphosed and strongly deformed.

Trans-North China orogeny in northern China - around 1850 million years BP

Due to all these numerous continent collisions and terran dockings, the supercontinent Columbia is formed towards the end of the Orosirium around 1800 million years BP .

literature

James Ogg: Status of Divisions of the International Geologic Time Scale . In: Lethaia . tape 37 , no. 2 , June 1, 2004, ISSN 1502-3931 , p. 183–199 , doi : 10.1080 / 00241160410006492 ( stratigraphy.org ( memento of September 29, 2007 in the Internet Archive ) [PDF]).
Kenneth A. Plumb: New Precambrian time scale. In: Episodes. Volume 14, No. 2, Beijing 1991, pp. 134-140, ISSN 0705-3797 .

Web links

International Stratigraphic Chart 2009 (PDF; 485 kB).

Individual evidence

^ KC Condie: Episodic continental growth and supercontinents: a mantle avalanche connection? In: Earth Planet. Sci. Lett. tape 163 , no. 1-4 , 1998, pp. 97-108 .
↑ Rebekah Lundquist: Provenance Analysis of the Marquette Range Supergroup sedimentary rocks using U-Pb Isotope geochemistry on detrital zircons by LA-ICP-MS . In: 19th annual Keck Symposium . 2006.
^ ME Barley: The Pilbara Craton . In: MJ De Wit, LD Ashwal (Eds.): Greenstone Belts . Clarendon Press, Oxford / New York 1997, pp. 657-663 .
↑ DC Mishra, B. Singh, VW Tiwari, BS Gupta, MBSV Rao: Two cases of continental collisions and related tectonics during the Proterozoic period in India - insight from gravity modeling constrained by seismic and magnetotelluric studies . In: Precambrian Res. Band 99 , 2000, pp. 149-169 .
↑ David J. Scott, Nuno Machado: UPb geochronology of the northern Torngat Orogen, Labrador, Canada: a record of Palaeoproterozoic magmatism and deformation. In: Precambrian Research. 70, 1995, p. 169, doi: 10.1016 / 0301-9268 (94) 00038-S .
^ RG Park, among others: The Loch Maree Group: Paleoproterozoic subduction-accretion complex in the Lewisian of NW Scotland . In: Precambrian Research . tape 105 , 2001, p. 205-226 .
^ SA Wilde, GC Zhao, M. Sun: Development of the North China Craton during the late Archean and its final amalgamation at 1.8 Ga: some speculations on its position within a global Paleoproterozoic supercontinent . In: Gondwana Res. Band 5 , 2002, p. 85-94 .
^ JJW Rogers, M. Santosh: Configuration of Columbia, a Mesoproterozoic Supercontinent . In: Gondwana Res. Band 5 , 2002, p. 5-22 .

[1] KC Condie: Episodic continental growth and supercontinents: a mantle avalanche connection? In: Earth Planet. Sci. Lett. tape 163 , no. 1-4 , 1998, pp. 97-108 .

[2] Rebekah Lundquist: Provenance Analysis of the Marquette Range Supergroup sedimentary rocks using U-Pb Isotope geochemistry on detrital zircons by LA-ICP-MS . In: 19th annual Keck Symposium . 2006.

[3] ME Barley: The Pilbara Craton . In: MJ De Wit, LD Ashwal (Eds.): Greenstone Belts . Clarendon Press, Oxford / New York 1997, pp. 657-663 .

[4] DC Mishra, B. Singh, VW Tiwari, BS Gupta, MBSV Rao: Two cases of continental collisions and related tectonics during the Proterozoic period in India - insight from gravity modeling constrained by seismic and magnetotelluric studies . In: Precambrian Res. Band 99 , 2000, pp. 149-169 .

[5] David J. Scott, Nuno Machado: UPb geochronology of the northern Torngat Orogen, Labrador, Canada: a record of Palaeoproterozoic magmatism and deformation. In: Precambrian Research. 70, 1995, p. 169, doi: 10.1016 / 0301-9268 (94) 00038-S .

[Park-6] RG Park, among others: The Loch Maree Group: Paleoproterozoic subduction-accretion complex in the Lewisian of NW Scotland . In: Precambrian Research . tape 105 , 2001, p. 205-226 .

[7] SA Wilde, GC Zhao, M. Sun: Development of the North China Craton during the late Archean and its final amalgamation at 1.8 Ga: some speculations on its position within a global Paleoproterozoic supercontinent . In: Gondwana Res. Band 5 , 2002, p. 85-94 .

[8] JJW Rogers, M. Santosh: Configuration of Columbia, a Mesoproterozoic Supercontinent . In: Gondwana Res. Band 5 , 2002, p. 5-22 .