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2. Tholeiitic magma series - Wikipedia

   en.wikipedia.org/wiki/Tholeiitic_Magma_Series

   The tholeiitic magma series (/ ˌθoʊliˈaɪtɪk /) is one of two main magma series in subalkaline igneous rocks, the other being the calc-alkaline series. A magma series is a chemically distinct range of magma compositions that describes the evolution of a mafic magma into a more evolved, silica rich end member. Rock types of the tholeiitic ...

3. Calc-alkaline magma series - Wikipedia

   en.wikipedia.org/wiki/Calc-alkaline_magma_series

   The calc-alkaline magma series is one of two main subdivisions of the subalkaline magma series, the other subalkaline magma series being the tholeiitic series. A magma series is a series of compositions that describes the evolution of a mafic magma, which is high in magnesium and iron and produces basalt or gabbro, as it fractionally crystallizes to become a felsic magma, which is low in ...

4. Mafic - Wikipedia

   en.wikipedia.org/wiki/Mafic

   The mafic rocks also typically have a higher density than felsic rocks. The term roughly corresponds to the older basic rock class. [9] Mafic lava, before cooling, has a low viscosity, in comparison with felsic lava, due to the lower silica content in mafic magma. Water and other volatiles can more easily and gradually escape from mafic lava.

5. Metamorphism - Wikipedia

   en.wikipedia.org/wiki/Metamorphism

   Metamorphic grade is an informal indication of the amount or degree of metamorphism. [ 78 ] In the Barrovian sequence (described by George Barrow in zones of progressive metamorphism in Scotland), metamorphic grades are also classified by mineral assemblage based on the appearance of key minerals in rocks of pelitic (shaly, aluminous) origin:

6. Alkaline magma series - Wikipedia

   en.wikipedia.org/wiki/Alkaline_magma_series

   All alkaline series magmas are thought to have evolved from a primitive mafic alkaline magma, either an alkalic picrite basalt or an ankaramite. This evolves to an alkali olivine basalt or basanite. Thereafter the series branches to the sodic series, the potassic series, or the nephelinic, leucitic, and analcitic series. [1] [2]: Ch6

7. Fractional crystallization (geology) - Wikipedia

   en.wikipedia.org/wiki/Fractional_crystallization...

   1: olivine crystallizes; 2: olivine and pyroxene crystallize; 3: pyroxene and plagioclase crystallize; 4: plagioclase crystallizes. At the bottom of the magma reservoir, a cumulate rock forms. Fractional crystallization , or crystal fractionation , is one of the most important geochemical and physical processes operating within crust and mantle ...

8. Millennium Prize Problems - Wikipedia

   en.wikipedia.org/wiki/Millennium_Prize_Problems

   t. e. The Millennium Prize Problems are seven well-known complex mathematical problems selected by the Clay Mathematics Institute in 2000. The Clay Institute has pledged a US$ 1 million prize for the first correct solution to each problem. The Clay Mathematics Institute officially designated the title Millennium Problem for the seven unsolved ...

9. Collatz conjecture - Wikipedia

   en.wikipedia.org/wiki/Collatz_conjecture

   As an illustration of this, the parity cycle (1 1 0 0 1 1 0 0) and its sub-cycle (1 1 0 0) are associated to the same fraction ⁠ 5 / 7 ⁠ when reduced to lowest terms. In this context, assuming the validity of the Collatz conjecture implies that (1 0) and (0 1) are the only parity cycles generated by positive whole numbers (1 and 2 ...