Breccia, altered matrix with small pebbles. Blocks are up to 30 cm^3. Blocks are either vesicular and aphyric or with large equant plag xtals (pheno or clot flow?). Could this be remnant of T-vent collapse? 3 pieces of breccia, one with matrix and pheno-rich clast, 2 other pieces of pheno-poor clasts.
Volcanism on Unimak Island, Alaska, USA: a special focus on Shishaldin and Fisher volcanoes
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