AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
About Alaska's Volcanoes | Hazards from Alaska's Volcanoes | Map & Alphabetical List | Interactive Map | Eruption Search | Volcano Search 
You are here: Home > Volcano Information

Westdahl reported activity



Event Name : Westdahl 1795

Start: 1795 Observed

Lahar, debris-flow, or mudflow: BibCard
Tephra plume: BibCard
Eruption Type:Explosive
MaxVEI: 4 BibCard

Description: From Miller and others (1998): "Veniaminov (1840, p. 18) described an eruption in 1795 on the southwest end of Unimak Island, which most likely occurred at Westdahl. Coats (1950) attributed four eruptions in the late eighteenth century and early nineteenth century to Pogromni volcano. Based on recent observations from aircraft, however, Pogromni does not appear to have been active in historical time. The eruptions should probably be assigned to Westdahl."

From Veniaminov (1840, translated by Lydia T. Black and R.H. Geoghegan, 1984): "In regard to volcanic phenomena, Unimak Island has occupied the first place since antiquity, both for its extraordinary size or the height and position of the mountains located on it. About 1795, with the wind from the SW, the range on the SW end of Unimak blew up with a terrible thunder and an eruption of ash [pepel] or soot [sazha], white in color, in such a great quantity that, for several hours in the middle of the day, not only in the neighboring villages on Aliaksa but even on Unga, there was absolute darkness. The eternal ice, lying on that range, slid down along both sides together with a large quantity of water and burned rocks of different sizes. The last stopped about half-way along and formed a trench or a black belt visible even now. There are still signs in places where the water flows and where the ice, which had slid down the mountain, rested for several years (the vegetation has only just begun to appear there). Nowadays one notices that this very range, which had been at rest after the upheaval, in the last few years, in one place, began to grow or bulge out."

Additionally, Plummer (1898) reports that the southwest crater exploded and fell in.

Sapper (1927) assigns this eruption to his category b1, and estimates more than 1 cubic km (10^9 cubic m) of tephra was erupted.

Contact AVO Privacy Accessibility Information Quality FOIA
URL: www.avo.alaska.edu/volcanoes/activity.php
Page modified: March 30, 2017 14:36
Contact Information: AVO Web Team

twitter @alaska_avo
facebook alaska.avo
email Receive volcano updates by email: USGS VNS

This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G22AC00137

Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.