Snowball Earth
A Snowball Earth is a geohistorical hypothesis ...
- Example(s):
- during the Sturtian Glaciation from approximately 717 to 659 million years ago (mya).
- during the Marinoan Glaciation from about 650 to 635 mya.
- ...
- See: Global Cooling Period, Sturtian Glaciation, Marinoan, Gaskiers Glaciation, Baykonurian Glaciation, Neoproterozoic, Proterozoic, Huronian Glaciation, Historical Geology, Greenhouse and Icehouse Earth, Glacial Period.
References
2024
- (Wikipedia, 2024) ⇒ https://en.wikipedia.org/wiki/Snowball_Earth Retrieved:2024-3-25.
- The Snowball Earth is a geohistorical hypothesis that proposes during one or more of Earth's icehouse climates, the planet's surface became entirely or nearly entirely frozen with no liquid oceanic or surface water exposed to the atmosphere. The most academically referred period of such global glaciation is believed to have occurred sometime before 650 mya during the Cryogenian period.
Proponents of the hypothesis argue that it best explains sedimentary deposits that are generally believed to be of glacial origin at tropical palaeolatitudes and other enigmatic features in the geological record. Opponents of the hypothesis contest the geological evidence for global glaciation and the geophysical feasibility of an ice- or slush-covered ocean,[1] [2] and they emphasize the difficulty of escaping an all-frozen condition. Several unanswered questions remain, including whether Earth was a full snowball or a "slushball" with a thin equatorial band of open (or seasonally open) water. The snowball-Earth episodes are proposed to have occurred before the sudden radiation of multicellular bioforms known as the Cambrian explosion. The most recent snowball episode may have triggered the evolution of multicellularity.
- The Snowball Earth is a geohistorical hypothesis that proposes during one or more of Earth's icehouse climates, the planet's surface became entirely or nearly entirely frozen with no liquid oceanic or surface water exposed to the atmosphere. The most academically referred period of such global glaciation is believed to have occurred sometime before 650 mya during the Cryogenian period.