Andesite
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Type | Igneous Rock |
Texture | Aphanitic (Fine-grained) |
Origin | Extrusive/Volcanic |
Chemical Composition | Intermediate |
Color | Medium Gray |
Mineral Composition | Sodium – Calcium Plagioclase, Hornblende, Biotite |
Tectonic Environment | Convergent Boundary – both Island Arc-type and Andean-type subduction zones |