Isanotski 1795
Start: 1795 [1]
Event Type: Not an eruption
Description: Several historical eruptions have been attributed to Isanotski, most notably the explosive March 10, 1825 eruption. However, according to Alaska Volcano Observatory geologists, Isanotski shows no evidence of having any possibly Holocene vents. Alaska Volcano Observatory geologists flying over Isanotski in 1997, 1998, and 1999 failed to find any apparently Holocene vents on Isanotski, and saw only glacially polished rocks. Geologists from AVO insist that all historical eruptions of Isanotski instead be attributed to Shishaldin. Field investigations of Shishaldin reveal numerous Holocene vents, including a very large flank feature called "The Blister" that has melted through the modern ice cover of Shishaldin, and which could be the vent for eruptions during the 1800s. In addition, several streams draining from Shishaldin look capable of carrying large amounts of sediment to the sea (as described by Veniaminov for the March 10, 1825 eruption), but all of the streams draining Isanotski are heavily vegetated, suggesting that they did not carry large amount of sediment within the last few hundred years (Chris Nye, personal commun., 2004).
Coats (1950) lists Isanotski as erupting in 1795, but Veniaminov (1840) and Grewingk (1850) indicate differently. Veniaminov reports that "a small mountain peak located not far away [from Pogromni] began to burn and continued to emit flame until 1795 or until the upheaval of the southwest range, lying to the S of Pogromskaia sopka." From this description, the 1795 activity is probably from Westdahl.
Coats (1950) lists Isanotski as erupting in 1795, but Veniaminov (1840) and Grewingk (1850) indicate differently. Veniaminov reports that "a small mountain peak located not far away [from Pogromni] began to burn and continued to emit flame until 1795 or until the upheaval of the southwest range, lying to the S of Pogromskaia sopka." From this description, the 1795 activity is probably from Westdahl.
References Cited
[1] Notes on the islands of the Unalaska district [translated from Russian by Lydia T. Black and R.H. Geoghegan in 1984], 1840
Veniaminov, Ivan, 1840, Notes on the islands of the Unalaska district [translated from Russian by Lydia T. Black and R.H. Geoghegan in 1984]: Pierce, R. A., (ed.), Kingston, Ontario, Limestone Press, 511 p.[2] Grewingk's geology of Alaska and the Northwest Coast of America [edited by Marvin W. Falk, translation by Fritz Jaensch published 2003], 1850
Grewingk, Constantine, 1850, Grewingk's geology of Alaska and the Northwest Coast of America [edited by Marvin W. Falk, translation by Fritz Jaensch published 2003]: Rasmuson Library Historical Translation Series 11, Fairbanks, AK, The University of Alaska Press, 242 p.[3] Catalog of the historically active volcanoes of Alaska, 1998
Miller, T. P., McGimsey, R. G., Richter, D. H., Riehle, J. R., Nye, C. J., Yount, M. E., and Dumoulin, J. A., 1998, Catalog of the historically active volcanoes of Alaska: U.S. Geological Survey Open-File Report 98-0582, 104 p.
intro and TOC PDF 268 KB
references PDF 43 KB Complete Eruption References
Catalog of the historically active volcanoes of Alaska, 1998
Miller, T. P., McGimsey, R. G., Richter, D. H., Riehle, J. R., Nye, C. J., Yount, M. E., and Dumoulin, J. A., 1998, Catalog of the historically active volcanoes of Alaska: U.S. Geological Survey Open-File Report 98-0582, 104 p.
intro and TOC PDF 268 KB
references PDF 43 KB 
Volcanoes of the world [2nd edition], 1994
Simkin, Tom, and Siebert, Lee, 1994, Volcanoes of the world [2nd edition]: Tucson, Arizona, Geoscience Press, 349 p.
Hard Copy held by AVO at FBKS - CEC shelf
Volcanic activity in the Aleutian Arc, 1950
Coats, R. R., 1950, Volcanic activity in the Aleutian Arc: U.S. Geological Survey Bulletin 0974-B, p. 35-49, 1 sheet, scale 1:5,000,000.
plate 1 PDF 819 KB
full-text PDF 783 KB 
Grewingk's geology of Alaska and the Northwest Coast of America [edited by Marvin W. Falk, translation by Fritz Jaensch published 2003], 1850
Grewingk, Constantine, 1850, Grewingk's geology of Alaska and the Northwest Coast of America [edited by Marvin W. Falk, translation by Fritz Jaensch published 2003]: Rasmuson Library Historical Translation Series 11, Fairbanks, AK, The University of Alaska Press, 242 p.
Hard Copy held by AVO at FBKS - CEC shelf
Notes on the islands of the Unalaska district [translated from Russian by Lydia T. Black and R.H. Geoghegan in 1984], 1840
Veniaminov, Ivan, 1840, Notes on the islands of the Unalaska district [translated from Russian by Lydia T. Black and R.H. Geoghegan in 1984]: Pierce, R. A., (ed.), Kingston, Ontario, Limestone Press, 511 p.
Hard Copy held by AVO at FBKS - CEC file cabinet