0.8-cm-thick tephra layer that is 32 cm from the base of the 1912 Novarupta fallout layer. Pl>opx>cpx+/-tr hb; opx:cpx = 5:1. Median diameter is 0.35 mm and maximum pumice length is 8 mm. Persistant layer that stands out prominently in the section; poorly sorted and contains a distinctive assemblage of abundant yellowed plagioclase and slightly greenish mica, some soapy green amphibole, oxidized magnetite, subequal proportions of opx and cpx, and a small fraction of frothy glass shards. Dark-brown, crystal-rich, and loosely consolidated tuffaceous-looking lithic clasts also present.
Explosive eruptive record in the Katmai region, Alaska Peninsula: an overview
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