Okmok reported activity

Event Name : Okmok 400 yBP

Start: 400	Years BP C-14 (raw)
Stop: 300	Years BP C-14 (raw)

Lahar, debris-flow, or mudflow:
Caldera lake change:

Description: From Beget and others (2005): "There is evidence that a lake filled the caldera to a depth of 150 meters over a period of several hundred years. The caldera lake drained catastrophically after failure of part of the caldera rim. The resultant flood caused deep erosion of the landscape on the north side of the volcano (Wolfe, 2001). Lahar deposits are present at low elevations in many of the stream valleys draining the volcano, and can be traced up to 12 kilometers down valley from the caldera rim. At most sites only a single lahar deposit is exposed, but at least three lahars, each more than 1 meter thick, occur in sea cliffs near the mouth of Ginger Creek on the west flank of the volcano, and are exposed intermittently for more than 2 kilometers along the beach. Radiocarbon dates suggest these lahars were emplaced 300 to 400 years ago."