Andesite

Andesite is an extrusive volcanic rock of intermediate composition. In a general sense, it is the intermediate type between basalt and rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende.


Andesite is an extrusive volcanic rock of intermediate composition. In a general sense, it is the intermediate type between basalt and rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende.
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