![]() "Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago". "Pb–Pb chronometry and the early Solar System". Nutman, Allen Papineau, Dominic Pirajno, Franco, "A Chronostratigraphic Division of the Precambrian", The Geologic Time Scale, Elsevier, pp. 299–392, doi: 10.1016/b978-5-9.00016-0, ISBN 978-5-9, retrieved (2012), Altermann, Wladyslaw Beard, Brian L. The name Hadean was coined by geologist Preston Cloud for the pre-Isuan sequence whose record may not be preserved on Earth but is better known from Moon rocks. Formation and evolution of the Solar System.Proposed Chaotian time intervals (2012) Eon Proposed Chaotian time intervals (2010) Eon The revised proposal in 2012 did not subdivide the proposed Chaotian era (of the Hadean eon) into periods. The Hadean period started with the creation of the Earth approximately 4.5 billion years ago (Ga) and concluded around 3.8 Ga. No numerical upper age limits were provided, only the younger age limit of ~4.5 Ga for the boundary between the proposed Chaotian and Hadean boundary. The original proposal in 2010 divided the Chaotian into two eras and four periods. 4.404 Ga detrital zircon from the Jack Hills of the Narryer Terrane in Western Australia.Īs of 26 December 2020 neither proposal had been adopted or officially ratified by the International Union of Geological Sciences. Collectively, the Hadean, Archean, and Proterozoic are sometimes informally referred to as the 'Precambrian. Earth's history is characterized by four eons in order from oldest to youngest, these are the Hadeon, Archean, Proterozoic, and Phanerozoic. 4.567 Ga and the oldest preserved crustal material on Earth, a c. The eon is the broadest category of geological time. ![]() This proposal defines the Chaotian eon as a solar system wide time between the initiation of planetary formation and the hypothesised collision of the Protoplanet Theia with the proto-Earth.Ī revised proposal in 2012 suggested the Chaotian as the first era of the Hadean representing the time between the formation of the solar system c. First proposed in 2010 as an eon, it is named after Chaos, the primeval void in Greek mythology. The Chaotian is a proposed time division of the geologic time scale. G., 2010Ĭollision between Proto-Earth and the Protoplanet Theia
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