I-type granite
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I-type granite is a type of granitoid that originates from igneous source rocks. It is characterized by moderate amounts of aluminum oxide (Al₂O₃) and high amounts of sodium oxide (Na₂O). Amphibole and pyroxene are commonly found in I-type granitoids. This type of granite is often found closer to oceanic trenches and contains hornblende as its mafic mineral. It is enriched in sodium and calcium and exhibits mantle chemical signatures. Granite, in general, is a coarse-grained intrusive igneous rock rich in quartz and feldspar, forming from cooling magma deep within the Earth's crust.12
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graniteThese result in I-type granitoids, derived from igneous protoliths and containing moderate amounts of Al2O3 and high amounts of Na2O, and S-type granitoids, derived from sedimentary protoliths and containing high amounts of Al2O3 and relatively low amounts of Na2O. Amphibole and pyroxene are more common in I-type granitoids,…
Read MoreThese result in I-type granitoids, derived from igneous protoliths and containing moderate amounts of Al2O3 and high amounts of Na2O, and S-type granitoids, derived from sedimentary protoliths and containing high amounts of Al2O3 and relatively low amounts of Na2O. Amphibole and pyroxene are more common in I-type granitoids,…
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igneous rockConvergent plate boundaries…chemical signatures; it is called I-type granite. The other type, called S-type granite, has muscovite and biotite and is depleted in sodium but enriched in aluminum such that corundum occurs in the norm and isotopic signatures. This suggests that such granites were formed by partial fusion of sedimentary rocks.
Read More…chemical signatures; it is called I-type granite. The other type, called S-type granite, has muscovite and biotite and is depleted in sodium but enriched in aluminum such that corundum occurs in the norm and isotopic signatures. This suggests that such granites were formed by partial fusion of sedimentary rocks.
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