Search results
Results from the WOW.Com Content Network
The tholeiitic magma series (/ ˌ θ oʊ l i ˈ aɪ 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. Rock types of the ...
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 ...
AFM ternary diagram showing the relative proportions of Na 2 O + K 2 O (A for Alkali earth metals), FeO + Fe 2 O 3 (F), and MgO (M) with arrows showing the path of chemical variation in tholeiitic and calc-alkaline series magmas. Magmas are further divided into three series: The tholeiitic series – basaltic andesites and andesites.
The alkaline series – subgroups of alkaline basalts and the rare, very high potassium-bearing (i.e. shoshonitic) lavas. This volcanic series is related to the age of the subduction zone and the depth. The tholeiitic magma series is well represented above young subduction zones formed by magma from relative shallow depth.
English: The AFM diagram, a ternary diagram between the Alkali, Fe, and Mg oxides used to distinguish the calc-alkaline magma series from the tholeiitic magma series. Key/Legend: A–alkali (sodium and potassium) oxides, F–iron oxides, M–magnesium oxide, BT–tholeiitic basalt, FB–ferro-basalt, ABT–tholeiitic basaltic andesite, AT–tholeiitic andesite, D–dacite, R–rhyolite, B ...
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 ...
A new small study suggests that athletes will perform better if they soak in a hot tub rather than a frigid one, especially if there are breaks in their workouts.
This page was last edited on 13 May 2011, at 22:28 (UTC).; Text is available under the