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  2. 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 ...

  3. Alkaline magma series - Wikipedia

    en.wikipedia.org/wiki/Alkaline_magma_series

    Rocks in the alkaline magma series are distinguished from rocks in the subalkaline tholeiitic and calc-alkaline magma series by their high content of alkali metal oxides (K 2 O plus Na 2 O) relative to silica (SiO 2). They are distinct from the rare peralkaline magmas, which have excess alkali oxides relative to alumina (Na 2 O + K 2 O > Al 2 O 3).

  4. Category:Calc-alkaline rocks - Wikipedia

    en.wikipedia.org/wiki/Category:Calc-alkaline_rocks

    Pages in category "Calc-alkaline rocks" The following 2 pages are in this category, out of 2 total. This list may not reflect recent changes. C.

  5. Carbonatite - Wikipedia

    en.wikipedia.org/wiki/Carbonatite

    Carbonatite liquid compositions are significantly more alkaline than what is preserved in the fossil carbonatite rock record as composition of the melt inclusions shows. [4] Only one carbonatite volcano is known to have erupted in historical time, the active Ol Doinyo Lengai volcano in Tanzania. It erupts with the coolest lava in the world, at ...

  6. Volcanic arc - Wikipedia

    en.wikipedia.org/wiki/Volcanic_arc

    In the rock record, volcanic arcs can be recognized from their thick sequences of volcaniclastic rock (formed by explosive volcanism) interbedded with greywackes and mudstones and by their calc-alkaline composition. In more ancient rocks that have experienced metamorphism and alteration of their composition (metasomatism), calc-alkaline rocks ...

  7. Tholeiitic magma series - Wikipedia

    en.wikipedia.org/wiki/Tholeiitic_Magma_Series

    The tholeiitic magma series (/ ˌ θ oʊ l eɪ ˈ ɪ t ɪ k /) 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.

  8. Shoshonite - Wikipedia

    en.wikipedia.org/wiki/Shoshonite

    File:Shoshonite lava flows on South Table Mountain, Colorado. Shoshonite is a type of igneous rock.More specifically, it is a potassium-rich variety of basaltic trachyandesite, [1] composed of olivine, augite and plagioclase phenocrysts in a groundmass with calcic plagioclase and sanidine and some dark-colored volcanic glass.

  9. Magma - Wikipedia

    en.wikipedia.org/wiki/Magma

    These magmas form rocks of the calc-alkaline series, an important part of the continental crust. [71] With low density and viscosity, hydrous magmas are highly buoyant and will move upwards in Earth's mantle. [72]