Calymmium

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 calymmian is 200 million years lasting period of the Proterozoic . Its beginning is determined radiometrically at 1,600 million years BP and its end at 1,400 million years BP. With the Calymmium, the Mesoproterozoic began and the Paleoproterozoic ended. The calymmium follows the period of the statherium and is in turn replaced by the ectasium , the second period of the Mesoproterozoic.

Naming

The name is derived from ancient Greek κάλυμμα (kalymma) meaning shell . This should indicate the worldwide expansion of sediment layers (also of volcanic origin) on existing or recently crystallized shelf platforms .

stratigraphy

Significant sedimentary basins and geological formations

• Bangemall Supergroup in the Bangemall Basin on the Capricorn Orogen in Western Australia - 1620 to 1070 million years BP
  • Edmund Group - 1620 to 1465 million years old BP
• Vindhya supergroup in northern India - 1700-600 million years BP
  • Semri Group - 1700 to about 1590 million years BP
    • Rohtas Formation - 1601 to 1599 million years BP
    • Rampur Shale - 1602 to 1593 million years BP
• Gaoyuzhuang system of the North China Craton - 1425-1348 million a BP
  • Guandi Formation - around 1425 million years BP with stromatolites

Geodynamics

Events

The supercontinent Columbia finally broke up around 1500 million years ago .

Igneous accretion belts

• Rio Negro Jaruena Belt in Brazil - 1800 to 1550 million years BP
• Arunta Terran in Australia - 1800 to 1500 million years old BP
  • Southwark Granite Sequence (around 1570 million years BP)
• Musgrave Terran in Australia - 1800 to 1500 million years old BP
• Mount Isa Terran in Queensland - 1800 to 1500 million years BP
  • Williams granite (batholith) - 1545 to 1490 million years old BP
  • Naraku granite (batholith) - 1545 to 1490 million years old BP
• Georgetown Terran in Queensland - 1800 to 1500 million years old BP
• Coen Terran in Australia - 1800 to 1500 million years BP
• Broken Hill Terran in New South Wales and South Australia - 1800 to 1500 million years old BP
• Mount Painter Terran in the Flinders Ranges in South Australia with 1575 to 1555 million year old granites
  • Mount Neill granite series - around 1575 million years BP
  • Moolawatana granite series - 1560 to 1555 million years BP

Orogenesis

• Chewings Orogeny :
  • on the southern edge of the North Australian craton - 1620 to 1580 million years BP
  • on the Arunta Terran - 1590 to 1560 million years BP
• Isa orogeny on Mount Isa Terran - around 1600 million years BP

See also

Geological timescale (overview)

literature

• James G. Ogg: Status on Divisions of the International Geologic Time Scale. Archived from the original on September 29, 2007. In: Lethaia . 37, 2004, pp. 183-199. doi : 10.1080 / 00241160410006492 .
• Kenneth A. Plumb: New Precambrian time scale. In: Episodes , 14 (2), Beijing 1991, pp. 134-140, ISSN  0705-3797 .

Web links

• International Stratigraphic Chart 2009 (PDF; 485 kB)

Individual evidence

1. ^ Wingate, MTD: Age and paleomagnetism of dolerite sills of the Bangemall Supergroup on the Edmund 1: 250,000 map sheet, WA . In: Record 2002/4 . Western Australia Geological Survey, 2002.
2. ↑ Martin, D. McB. and Thorne, AM: Tectonic setting and basin evolution of the Bangemall Supergroup in the northwestern Capricorn Orogen . In: Precambrian Research . tape 128 , 2004, pp. 385-409 .