Wrangell Mount Zanetti
Start: 50000 yBP ± 80000 Years [1]
Event Type: Effusive
- Lava flow [2]
Description: From Miller and others (1998): "Mt. Zanetti (3965 m) a large (350 m high) steep-sided, relatively undissected cinder-spatter cone occurs high on the northwest flank of the shield and may be the source of some lava flows. Lavas on the southwest flank have flowed as much as 59 km from their source despite being phenocryst-rich andesite, a mobility attributed to a very high eruptions rate (Nye, 1983)."
Richter and others (1995) state: "On the basis of radiometric dating K-Ar dating, the lava flows most recently erupted from Mount Wrangell may be 50,000 to 100,000 years old...the one of Mount Zanetti and a few flows on the south flank of Mount Wrangell are probably the youngest products of the volcano. Mount Zanetti probably erupted during the waning stage of the latest major glaciation, possibly less than 25,000 years ago, and a large, young andesite flow that originated in the summit area and traveled more than 40 m (64 km) south and west in the ancestral Copper River Basin may only be 50,000 years old."
From Richter and others (1990): "K-Ar ages of 0.05 and 0.06 Ma ([sample] no. 1) were determined on a large and extremely long andesite flow that debouched into the Copper River Basin probably in late Pleistocene time (Yehle and Nichols 1980). These determinations, however, have such large analytical uncertainties that meaningful ages cannot be assigned (JD Obradovich, personal communication 1979)."
Richter and others (1995) state: "On the basis of radiometric dating K-Ar dating, the lava flows most recently erupted from Mount Wrangell may be 50,000 to 100,000 years old...the one of Mount Zanetti and a few flows on the south flank of Mount Wrangell are probably the youngest products of the volcano. Mount Zanetti probably erupted during the waning stage of the latest major glaciation, possibly less than 25,000 years ago, and a large, young andesite flow that originated in the summit area and traveled more than 40 m (64 km) south and west in the ancestral Copper River Basin may only be 50,000 years old."
From Richter and others (1990): "K-Ar ages of 0.05 and 0.06 Ma ([sample] no. 1) were determined on a large and extremely long andesite flow that debouched into the Copper River Basin probably in late Pleistocene time (Yehle and Nichols 1980). These determinations, however, have such large analytical uncertainties that meaningful ages cannot be assigned (JD Obradovich, personal communication 1979)."
References Cited
[1] Reconnaissance map and description of the Chetaslina volcanic debris flow (new name), southeastern Copper River basin and adjacent areas, South-central Alaska, 1980
Yehle, L. A., and Nichols, D. R., 1980, Reconnaissance map and description of the Chetaslina volcanic debris flow (new name), southeastern Copper River basin and adjacent areas, South-central Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF 1209, unpaged, 1 sheet, scale 1:250,000.[2] Age and progression of volcanism, Wrangell volcanic field, Alaska, 1990
Richter, D. H., Smith, J. G., Lanphere, M. A., Dalrymple, G. B., Reed, B. L., and Shew, N., 1990, Age and progression of volcanism, Wrangell volcanic field, Alaska: Bulletin of Volcanology, v. 53, n. 1, p. 29-44.Complete Eruption References
Age and progression of volcanism, Wrangell volcanic field, Alaska, 1990
Richter, D. H., Smith, J. G., Lanphere, M. A., Dalrymple, G. B., Reed, B. L., and Shew, N., 1990, Age and progression of volcanism, Wrangell volcanic field, Alaska: Bulletin of Volcanology, v. 53, n. 1, p. 29-44.
Reconnaissance map and description of the Chetaslina volcanic debris flow (new name), southeastern Copper River basin and adjacent areas, South-central Alaska, 1980
Yehle, L. A., and Nichols, D. R., 1980, Reconnaissance map and description of the Chetaslina volcanic debris flow (new name), southeastern Copper River basin and adjacent areas, South-central Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF 1209, unpaged, 1 sheet, scale 1:250,000.
Hard Copy held by AVO at FBKS - CEC shelf
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 
Guide to the volcanoes of the western Wrangell Mountains, Alaska - Wrangell-St. Elias National Park and Preserve, 1995
Richter, D. H., Rosenkrans, D. S., and Steigerwald, M. J., 1995, Guide to the volcanoes of the western Wrangell Mountains, Alaska - Wrangell-St. Elias National Park and Preserve: U.S. Geological Survey Bulletin 2072, 31 p.
