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User:Tdaniels38/Neoarchean

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The Neoarchean is the last geologic era in the Archean eon that spans from 2.8 to 2.5 billion years ago and is marked by major developments in complex life and continental formation.

Continental formation

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During this era, the supercontinent Kenorland is proposed to have formed about 2.7 billion years ago.[1] Kenorland is of particular interest due to it containing deposits of volcanic-hosted massive sulphide (VHMS), gold, and uranium found in the Canadian shield. With new research, the validity of Kenorland has been questioned in favor of other Neoarchean supercontinent proposals Superia or Vaalbara.[2] Improved geologic knowledge suggests that a part of Kenorland, specifically the Churchill Province, was instead a continental development that formed after the Neoarchean era, Nuna, closer to 1.9 billion years ago.[2] This challenge to the reconstruction is based on research studying northern Kenorland's Paleoproterozoic cover as well as the suture between the Rae and Hearne cratons.

The supercontinent cycle can been studied through patterns that describe how Earth's crust and its mineral deposits were preserved over time since Pangaea.[2] Plate tectonics, having developed earlier in the Archean eon[3], produced the force necessary for metamorphism and magmatic activity which greatly contributed to these continental changes.[2] Research on how the supercontinents broke apart and combined into different configurations is involved in linking together deep-interior and surface-level processes as well as the assessment of contrasting models of early Paleoproterozoic geodynamic activity.[2]

References

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  1. ^ Bozhko, N. A. (2011). "On two types of supercontinental cyclicity". Moscow University Geology Bulletin. 66 (5): 313–322. doi:10.3103/S0145875211050036. ISSN 1934-8436.
  2. ^ a b c d e Pehrsson, Sally J.; Berman, Robert G.; Eglington, Bruce; Rainbird, Robert (2013). "Two Neoarchean supercontinents revisited: The case for a Rae family of cratons". Precambrian Research. Paleoproterozoic tectonic assembly of the western Canadian shield: new findings and implications for the reconstruction of Laurentia/Nuna. 232: 27–43. doi:10.1016/j.precamres.2013.02.005. ISSN 0301-9268.
  3. ^ Lepot, Kevin (2020). "Signatures of early microbial life from the Archean (4 to 2.5 Ga) eon". Earth-Science Reviews. 209: 103296. doi:10.1016/j.earscirev.2020.103296. ISSN 0012-8252.