page_title: Marinoan glaciation
section_title: Evidence
hierarchical_section_title: Marinoan glaciation / Evidence
caption_attribution_description: English: Elatina Fm diamictite, formed during the Cryogenian Period, adjacent to the Ediacaran GSSP site in Brachina Gorge, Flinders Ranges National Park; outcrop exposed in creek bed. $AUD1 coin for scale.
context_page_description: The Marinoan glaciation was a period of worldwide glaciation that lasted from approximately 650 to 635 Ma during the Cryogenian period. The glaciation may have covered the entire planet, in an event called the Snowball Earth. The end of the glaciation may have been sped by the release of methane from equatorial permafrost.
context_section_description: Even though much evidence has been lost through geological changes, field investigations show evidence of the Marinoan glaciation in China, Svalbard archipelago and South Australia.  In Guizhou Province, China, glacial rocks were found to be underlying and overlying a layer of volcanic ashes which contained zircon minerals, which could be dated through radioisotopes.  Glacial deposits in South Australia are approximately the same age (about 630 Ma), confirmed by similar stable carbon isotopes, mineral deposits (including sedimentary barite), and other unusual sedimentary structures.   Two diamictite-rich layers in the top 1 km (0.62 mi) of the 7 km (4.3 mi) Neoproterozoic strata of the northeastern Svalbard archipelago represent the first and final phases of the Marinoan glaciation.
  According to Eyles and Young, the Marinoan is a second episode of Neoproterozoic glaciation (680–690 Ma) occurring in the Adelaide Geosyncline.  According to them, "It is separated from the Sturtian by a thick succession of sedimentary rocks containing no evidence of glaciation.  This glacial phase could correspond to the recently described Ice Brooke formation in the northern Cordillera."
caption: Elatina Fm diamictite below Ediacaran GSSP site in the Flinders Ranges NP, South Australia. A$1 coin for scale.
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