Qcl - Cascade Bight lava flows. Thin (2-5 m) lava flows, exhibiting reddish scoriaceous tops and bottoms, dip away from summit breccia and plug area. Rocks are medium dark gray porphyritic basaltic andesites (55.1% SiO2) containing phenocrysts of plagiocl
Geologic map of Akutan Island, Alaska
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