Okmok 1500 yBP
Start: 1500 yBP [1]
Event Type: Explosive
- Tephrafall [1]
- Pyroclastic flow, surge, or nuee ardente [1]
- Cone [1]
Description: From Beget and others (2005): "Numerous post-caldera (younger than 2,000 years) pyroclastic flow and surge deposits are found associated with the young tuff cones within the caldera, and distal pyroclastic flow and surge deposits also occur on the west, north, and northeast flanks of Okmok Volcano as far as 14 kilometers from the caldera rim. The thickest set of young surge deposits outside of the caldera occurs on the west flank of Okmok about 8 kilometers from the caldera rim, where deposits of fine-grained surge beds containing incinerated plant remains and abundant accretionary lapilli are more than 6 meters thick. These deposits were emplaced about 1,500 years ago."
References Cited
[1] Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska, 2005
Beget, J.E., Larsen, J.F., Neal, C.A., Nye, C.J., and Schaefer, J.R., 2005, Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2004-3, 32 p., 1 sheet, scale 1:150,000.
full text of report 3.4 MB
map sheet 53.2 MB Complete Eruption References
Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska, 2005
Beget, J.E., Larsen, J.F., Neal, C.A., Nye, C.J., and Schaefer, J.R., 2005, Preliminary volcano-hazard assessment for Okmok Volcano, Umnak Island, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2004-3, 32 p., 1 sheet, scale 1:150,000.
full text of report 3.4 MB
map sheet 53.2 MB 