What phenocryst minerals would you expect to find in an aphanitic rhyolite flow?
A) quartz and K- feldspar
B) apatite and muscovite
C) intermediate (Ca- Na) plagioclase and amphibole or pyroxene
D) Ca- rich plagioclase and olivine

Question

Quizplus · Accepted Answer

Rhyolite is a high-silica volcanic rock that typically contains quartz and potassium feldspar (K-feldspar) as its primary phenocryst minerals. These minerals are indicative of the silica-rich magma from which rhyolite forms.

What Phenocryst Minerals Would You Expect to Find in an Aphanitic