0.81 to 0.5-cm-thick tephra layer that is 47 cm from the base of the 1912 Novarupta fallout layer. Pl>mica>amph>>cpx>=opx; opx:cpx = 1:1. Median diameter is 0.10 mm and maximum pumice length is 3 mm. Occurs a few cm below the upper pale tan ash and is sharply defined and persistant. Crystal-rich with a mixture of white-to-clear glass and distinctive dark brown to black, granular and friable lithic clasts.
Explosive eruptive record in the Katmai region, Alaska Peninsula: an overview
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