Paleohydrology of a catastrophic flood release from Okmok caldera and post-flood eruption history at Okmok Volcano, Umnak Island, Alaska
dc.contributor.author | Wolfe, Benjamin Alan | |
dc.date.accessioned | 2016-07-20T02:03:54Z | |
dc.date.available | 2016-07-20T02:03:54Z | |
dc.date.issued | 2001-08 | |
dc.identifier.uri | http://hdl.handle.net/11122/6716 | |
dc.description | Thesis (M.S.) University of Alaska Fairbanks, 2001 | en_US |
dc.description.abstract | Okmok caldera, located on the northeastern end of Umnak Island, Alaska, contained a 5.8 x 10⁹m³ lake that catastrophically drained as a result of failure of the 2050 yr. B.P. caldera rim between 1560 and 1010 yr. B.P. Flow competence equations, dam-break models, and the Simplified Dam-Break computer model were used to estimate the paleohydrology of the flood. Models indicate that the peak discharge at the breach in the caldera rim was at least 5.8 x 10⁴ m³/s, and the maximum possible discharge was 1.9 x 10⁶ m³/s. A second smaller flood release occurred 190 yr B.P., coinciding with the 1817 A.D. eruption, and destroyed a small Aleut village at Cape Tanak. Stratigraphic analysis reveals that Okmok Volcano has maintained a high level of volcanic activity following the large flood release. Major eruptive events producing air-fall tephra deposits average 1 every 80 years since 1010 yr. B.P. | en_US |
dc.language.iso | en_US | en_US |
dc.title | Paleohydrology of a catastrophic flood release from Okmok caldera and post-flood eruption history at Okmok Volcano, Umnak Island, Alaska | en_US |
dc.type | Thesis | en_US |
refterms.dateFOA | 2020-01-25T02:05:46Z |
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