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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 ...
Magnesium oxide (Mg O), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg 2+ ions and O 2− ions held together by ionic bonding .
[41] [42] Then, in 2008, Hazen and colleagues introduced a much broader and more detailed vision of mineral evolution. This was followed by a series of quantitative explorations of the evolution of various mineral groups. These led in 2015 to the concept of mineral ecology, the study of distributions of minerals in space and time. [42] [43]
Periclase is a magnesium mineral that occurs naturally in contact metamorphic rocks and is a major component of most basic refractory bricks. It is a cubic form of magnesium oxide (Mg O). In nature it usually forms a solid solution with wüstite (FeO) and is then referred to as ferropericlase or magnesiowüstite. [6]
Crystalline magnesium oxide, or periclase, has a calculated lattice energy of 3795 kJ mol-1 which must be overcome for it to go into solution or for reaction to occur. Reactive magnesia is essentially amorphous magnesia with low lattice energy and is made at low temperatures and finely ground. CCM is manufactured worldwide.
Geochemically, TTG rocks often have a high silica (SiO 2) content (commonly over 70 percent SiO 2), high sodium oxide (Na 2 O) content (with low K 2 O/Na 2 O ratio) compared to other plutonic rocks, and low ferromagnesian element content (the weight percentage of iron oxide, magnesium oxide, manganese dioxide, and titanium dioxide added ...
In both, magnesium oxide is the precursor to magnesium metal. The magnesium oxide is produced as a solid solution with calcium oxide by calcining the mineral dolomite, which is a solid solution of calcium and magnesium carbonates: CaCO 3 ·MgCO 3 → MgO·CaO + 2 CO 2. Reduction occurs at high temperatures with silicon.
Fossil evidence and associated elevated strontium levels in the 2nd and 3rd carbonate beds shows how the later lakes sustained more life and had a consistent freshwater source. This could have been a spring source in either the Tugen Hills to the East, or a paleoclimatic change leading to increasing rainfall, per current hypotheses.