Multiple Choice
What phenocryst minerals would you expect to find in a porphyritic andesite?
A) intermediate (Ca-Na) plagioclase and amphibole or pyroxene
B) Na-rich plagioclase and K-feldspar
C) Ca-rich plagioclase and olivine
D) muscovite and biotite
Correct Answer:
Verified
Correct Answer:
Verified
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