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  2. Greenstone belt - Wikipedia

    en.wikipedia.org/wiki/Greenstone_belt

    Greenstones, aside from containing basalts, also give rise to several types of metamorphic rocks which are used synonymously with 'metabasalt' et cetera; greenschist, whiteschist and blueschist are all terms spawned from the study of greenstone belts. The West African early Proterozoic greenstone belts are similar to the Archean greenstone belts.

  3. Tectonic evolution of the Barberton greenstone belt - Wikipedia

    en.wikipedia.org/wiki/Tectonic_evolution_of_the...

    These sinking greenstones forced the granitic partial melts sideways and upwards, emplacing them into the margins of the belt and later folding them. The greenstone cover allows the granitic layer to remobilize and form the dome structure. This two stage event is dated between 3.26 and 3.22 Ga. [10]

  4. Birimian - Wikipedia

    en.wikipedia.org/wiki/Birimian

    The Birimian forms two distinct and ... were formed by the collision of the Archean Cupixi-Carajas craton in the ... and the Lower Birimian greenstones.

  5. Archean life in the Barberton Greenstone Belt - Wikipedia

    en.wikipedia.org/wiki/Archean_life_in_the...

    The Barberton Greenstone Belt is located on the Kaapvaal craton, which covers much of the southeastern part of Africa, and was formed by the emplacement of granitoid batholiths. [7] The Kaapvaal craton was once part of a supercontinent geologists term Vaalbara that also included the Pilbara craton of western Australia. [ 7 ]

  6. Greenschist - Wikipedia

    en.wikipedia.org/wiki/Greenschist

    The greenstone belts of the various Archean cratons are commonly altered to the greenschist facies. These ancient rocks are noted as host rocks for a variety of ore deposits in Australia, Namibia and Canada. Greenschist-like rocks can also be formed under blueschist facies conditions if the original rock contains enough magnesium.

  7. Isua Greenstone Belt - Wikipedia

    en.wikipedia.org/wiki/Isua_Greenstone_Belt

    A large number of geological and geochemical methods have been applied to the rocks of the Isua Greenstone Belt. These include subdivision of the various lithologies and units within the belt using a combination of geological mapping and U-Pb zircon dating, typically using sensitive high-resolution ion microprobe (SHRIMP), analyses; [3] major and trace element chemistry; [11] [12] structural ...

  8. A Study Tells the Truth About How the First Continents Formed ...

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  9. List of orogenies - Wikipedia

    en.wikipedia.org/wiki/List_of_orogenies

    Lopian orogeny – Archean orogeny – Formation of two different types of terrain compatible with plate tectonic concepts. One is a belt of high-grade gneisses formed in a regime of strong mobility, while the other is a region of granitoid intrusions and greenstone belts surrounded by the remnants of a Saamian substratum, (2.9–2.6 Ga)