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The Paleoproterozoic Era [4] (also spelled Palaeoproterozoic) is the first of the three sub-divisions of the Proterozoic eon, and also the longest era of the Earth's geological history, spanning from (2.5–1.6 Ga).
Well-identified events of this eon were the transition to an oxygenated atmosphere during the Paleoproterozoic; the evolution of eukaryotes via symbiogenesis; several global glaciations, which produced the 300 million years-long Huronian glaciation (during the Siderian and Rhyacian periods of the Paleoproterozoic) and the hypothesized Snowball ...
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]
Tappania plana appears in Paleoproterozoic formations of India and northern China (Baicaoping and Beidajian), both with an age of 1,630 mya. It is a roughly spherical acritarch, 30-60 μm in diameter, with one or two small necks. Small branched and / or partitioned tubes emerge from the central body.
The Rhyacian Period (/ r aɪ ˈ eɪ s i. ə n /; Ancient Greek: ῥύαξ, romanized: rhýax, meaning "stream of lava") is the second geologic period in the Paleoproterozoic Era and lasted from 2300 Mya to 2050 Mya (million years ago). [2] Instead of being based on stratigraphy, these dates are defined chronometrically. [3]
A tectonic evolution diagram from 2.45 Ga to 1.95 Ga, proposed by Zhao et al. [4] (1) At around 2.45 Ga, the oceanic crust of Ordos Block was subducted beneath Yinshan Block, making igneous rocks. (2) Sedimentary rocks deposited in Ordos Block between 2.0-1.95 Ga. (3) Both continents of Yinshan Block and Ordos Block met at around 1.95 Ga and an ...
The Eburnean orogeny, or Eburnean cycle, was a series of tectonic, metamorphic and plutonic events in what is now West Africa during the Paleoproterozoic era about 2200–2000 million years ago. During this period the Birimian domain in West Africa was established and structured. [2] [3] [4]
The Siderian Period (/ s aɪ ˈ d ɪər i. ə n, s ɪ-/; Ancient Greek: σίδηρος, romanized: sídēros, meaning "iron") is the first geologic period in the Paleoproterozoic Era and lasted from 2500 Ma to 2300 Ma. Instead of being based on stratigraphy, these dates are defined chronometrically.