Welded tuff. Black cinders(highly vesicular) large dense clasts, lithics. Largest lithics are ~4 cm. Base is uncertain, but ~ 6m wall exposed. Exposures are on both sides of creek, opposite wall downstream shows ~ 10 m thick section. Deposit is poorly welded. Some banded pumice seen, but rare. Large, dense blocks have oxidation rinds up to 2 cm thick and have lithics within, some up to ~1.5 cm. Single black scoria bomb, broken up. Highly vesicular. Very few xtals, nearly aphyric.
Volcanism on Unimak Island, Alaska, USA: a special focus on Shishaldin and Fisher volcanoes