Page 362 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists
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Properties Tectonic classification of texture (grain rocks commonly percentages them exhibit also that makes (chemical include: silica in plagioclase sodium are silica ((Mg,Fe),SiO,]; calcium factor the in molecules the while the more magma thus silica in like freely, more melting lower magmas melt, with silica of properties. High formed therefore rocks When are that
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APPENDIX. Igneous Classification, Magmas, Occurrence CLASSIFICATION CHART The next the on chart to content tchemical silica names rough a are guide between falling silica the rocks igneous the and types rock shown. (SiO,)-* Silica Content Silica (Si) silicon is and mineral a of example that found minerals igneous in feldspar potassium (muscovite, micas and minerals igneous in N

