Spurr non-eruptive activity 2021
Start: 13:22:00 April 7, 2021 [1]
Stop: 13:24:00 April 7, 2021 [1]
Event Type: Not an eruption
- Debris-avalanche, volcanic avalanche, or landslide [1]
Description: From Orr and others, 2024: "Although no eruptive activity or unrest took place at Mount Spurr in 2021, one notable ice and rock avalanche was large enough to be recorded by regional geophysical sensors. This mass movement signal was recorded on Mount Spurr’s local seismic network on April 7 at 05:22 AKDT (13:22 UTC). The event's seismic waveforms indicated that it had a duration of ~2 minutes. Acoustic waves were likewise detected at station SPCP (on Mount Spurr) and at KENI infrasound array (near the City of Kenai, Alaska); these waves also had a coherent signal duration of ~2 minutes. No clear satellite views were available for this event, precluding AVO from identifying a precise source or deposit area and estimating the avalanche volume. However, the peak period of the long-period (LP) seismic energy was ~15 seconds, indicating that the event was smaller than the widely recorded Mount Spurr ice and rock avalanche of July 15, 2019 (Orr and others, 2023)."
References Cited
[1] 2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands - Summary of events and response of the Alaska Volcano Observatory, 2024
Orr, T.R., Dietterich, H.R., Fee D., Girona, T., Grapenthin, R., Haney, M.M., Loewen, M.W., Lyons, J.J., Power, J.A., Schwaiger, H.F., Schneider, D.J., Tan, D., Toney, L., Wasser, V.K., and Waythomas, C.F., 2024, 2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands - Summary of events and response of the Alaska Volcano Observatory: U.S. Geological Survey Scientific Investigations Report 2024-5014, 64 p. https://doi.org/10.3133/sir20245014.
Full-text PDF 25.7 MB Complete Eruption References
2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands - Summary of events and response of the Alaska Volcano Observatory, 2024
Orr, T.R., Dietterich, H.R., Fee D., Girona, T., Grapenthin, R., Haney, M.M., Loewen, M.W., Lyons, J.J., Power, J.A., Schwaiger, H.F., Schneider, D.J., Tan, D., Toney, L., Wasser, V.K., and Waythomas, C.F., 2024, 2021 Volcanic activity in Alaska and the Commonwealth of the Northern Mariana Islands - Summary of events and response of the Alaska Volcano Observatory: U.S. Geological Survey Scientific Investigations Report 2024-5014, 64 p. https://doi.org/10.3133/sir20245014.
Full-text PDF 25.7 MB