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The Mesoproterozoic Oxygenation Event
Science China Earth Sciences, 2021The accumulation of oxygen is one of the most important characteristics that distinguish Earth from other planets in the solar system, which is also considered to be the key factor influencing the birth and evolution of complex life forms. The oxygenation process of the Earth surface has long been viewed to be episodic with two critical intervals ...
Shuichang Zhang +3 more
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Revisiting the Mesoproterozoic
Gondwana Research, 2021Abstract Many of the peculiar features of the Mesoproterozoic (1.6–1.0 Ga) are related to the assembly of the first supercontinent Nuna, and some may not be distinctive of this time period. A high frequency of A-type granites at 1.6–1.4 Ga may be due, in part, to sampling biases.
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Mesoproterozoic basins of Australia
2023The preserved successions from the Mesoproterozoic Era (1600 to 1000 Ma) are a relatively understudied part of Australian geological evolution, especially considering that this era has a greater time span than the entire Phanerozoic. These rocks are mostly known in variably-preserved sedimentary basins overlying Paleoproterozoic or Archean cratons or ...
J., Anderson +3 more
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Mesoproterozoic paleogeography: Supercontinent and beyond
Precambrian Research, 2014A set of global paleogeographic reconstructions for the 1770–1270 Ma time interval is presented here through a compilation of reliable paleomagnetic data (at the 2009 Nordic Paleomagnetic Workshop in Lulea, Sweden) and geological constraints. Although currently available paleomagnetic results do not rule out the possibility of the formation of a ...
Pisarevsky, Sergei +3 more
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Organomineralization in Mesoproterozoic giant ooids
Journal of Asian Earth Sciences, 2015Abstract Ooids are common carbonate particles that are traditionally considered as abiogenically formed by physical and chemical processes in highly agitated environments. Recent studies point to the importance of microbial activities in ooid formation, but more case studies are required to confirm and clarify the roles of microbes and their ...
Dongjie Tang +5 more
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Lithostratigraphy of the Mesoproterozoic Twakputs Gneiss
South African Journal of Geology, 2021Abstract The Twakputs Gneiss is a garnetiferous, K-feldspar megacrystic, biotite granite-granodiorite orthogneiss. It represents a major unit in the Kakamas Domain of the Mesoproterozoic Namaqua-Natal Metamorphic Province extending about 250 km between Riemvasmaak in South Africa and Grünau in southern Namibia. The Twakputs Gneiss occurs
Doggart, S, Macey, P, Frei, D
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Mesoproterozoic Archaeoellipsoidès : akinetes of heterocystous cyanobacteria
Lethaia, 1995The genus Archaeoellipsoides Horodyski & Donaldson comprises large (up to 135 micrometers long) ellipsoidal and rod-shaped microfossils commonly found in silicified peritidal carbonates of Mesoproterozoic age. Based on morphometric and sedimentary comparisons with the akinetes of modern bloom-forming Anabaena species, Archaeoellipsoides is interpreted ...
S, Golubic, V N, Sergeev, A H, Knoll
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Superchron at the Mesoproterozoic-Neoproterozoic transition
Doklady Earth Sciences, 2009The search for old superchrons represents an important direction in the study of geomagnetic field evolution. According to recent terminology, the superchron is a time interval (and corresponding state of the geomagnetic field), during which the process of reversal of the geomagnetic field polarity that is characteristic of any other period of ...
Pavlov, V. E., Gallet, Y.
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Lithostratigraphy of the Mesoproterozoic Kliphoek Granite
South African Journal of Geology, 2016The Kliphoek Granite is a mesocratic, porphyritic post-tectonic granite in the western Namaqualand sector of the Mesoproterozoic Namaqua-Natal Belt. It was mapped as one of 26 different types of granite of the Spektakel Suite by Council for Geoscience geologists.
C.H. de Beer, P.H. Macey
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The Mesoproterozoic Irumide belt of Zambia
Journal of African Earth Sciences, 2006The Mesoproterozoic Irumide belt is a northeast-trending structural province stretching from central Zambia to the Zambia–Tanzania border and northern Malawi. Mesoproterozoic and Neoproterozoic transcurrent shear zones within reactivated parts of the Palaeoproterozoic Ubendian belt define its northeastern limit.
B. De Waele +3 more
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