Pavlof unrest 2019/12
Start: December 28, 2019 [1]
Event Type: Not an eruption
- Seismicity with no confirmed eruption [1]
Description: From Orr and others, 2023: "In 2019, Pavlof Volcano showed signs of weak activity that caused AVO to raise the Aviation Color Code and Volcano Alert Level to YELLOW and ADVISORY three times...AVO raised the Aviation Color Code and Volcano Alert Level to YELLOW and ADVISORY for the last time on December 28, again on the basis of an increase in seismic tremor levels. Ash emissions from the volcano were not observed during any unrest periods in 2019.
"A total of 90 earthquakes were located within 20 km of Pavlof Volcano during 2019. Of these events, 44 were classified as volcano-tectonic (VT) earthquakes, with a collective depth range of −2.85 to 31.5 km and a local magnitude (ML) range of −0.41 to 1.65. The other 46 were classified as LP earthquakes, with a depth range of 8 to 34 km and a ML range of −0.36 to 1.65. Of the 46 LP events, 21 were located ~5 km northeast of Pavlof Volcano beneath Pavlof Sister, a pattern also seen in the seismicity of previous years (Power and others, 2004b). AVO recorded several tremor episodes at Pavlof Volcano in 2019. There is no obvious temporal relationship between the tremor and the earthquake activity...The activity of 2019 ended with additional tremor pulses that took place on October 18 and December 14.
"The annual number of earthquakes located at Pavlof Volcano increased between 2017 and 2019. This trend is probably influenced by improvements made to Pavlof Volcano’s seismic network in the summer of 2017, but the fact that AVO located significantly fewer events in 2019 than 2018 suggests a change in activity level unrelated to the network improvements."
"A total of 90 earthquakes were located within 20 km of Pavlof Volcano during 2019. Of these events, 44 were classified as volcano-tectonic (VT) earthquakes, with a collective depth range of −2.85 to 31.5 km and a local magnitude (ML) range of −0.41 to 1.65. The other 46 were classified as LP earthquakes, with a depth range of 8 to 34 km and a ML range of −0.36 to 1.65. Of the 46 LP events, 21 were located ~5 km northeast of Pavlof Volcano beneath Pavlof Sister, a pattern also seen in the seismicity of previous years (Power and others, 2004b). AVO recorded several tremor episodes at Pavlof Volcano in 2019. There is no obvious temporal relationship between the tremor and the earthquake activity...The activity of 2019 ended with additional tremor pulses that took place on October 18 and December 14.
"The annual number of earthquakes located at Pavlof Volcano increased between 2017 and 2019. This trend is probably influenced by improvements made to Pavlof Volcano’s seismic network in the summer of 2017, but the fact that AVO located significantly fewer events in 2019 than 2018 suggests a change in activity level unrelated to the network improvements."
References Cited
[1] 2019 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory, 2023
Orr, T.R., Cameron, C.E., Dietterich, H.R., Dixon, J.P., Enders, M.L., Grapenthin, R., Iezzi, A.M., Loewen, M.W., Power, J.A., Searcy, C., Tepp, G., Toney, L., Waythomas, C.F., and Wech, A.G., 2023, 2019 Volcanic activity in Alaska - Summary of events and response of the Alaska Volcano Observatory: U.S. Geological Survey Scientific Investigations Report 2023-5039, 64 p., https://doi.org/10.3133/sir20235039.
Full-text PDF 14.3 MB Complete Eruption References
2019 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory, 2023
Orr, T.R., Cameron, C.E., Dietterich, H.R., Dixon, J.P., Enders, M.L., Grapenthin, R., Iezzi, A.M., Loewen, M.W., Power, J.A., Searcy, C., Tepp, G., Toney, L., Waythomas, C.F., and Wech, A.G., 2023, 2019 Volcanic activity in Alaska - Summary of events and response of the Alaska Volcano Observatory: U.S. Geological Survey Scientific Investigations Report 2023-5039, 64 p., https://doi.org/10.3133/sir20235039.
Full-text PDF 14.3 MB Automatic identification and quantification of volcanic hotspots in Alaska using HotLINK: the hotspot learning and identification network, 2024
Saunders-Schultz, P., Lopez, T., Dietterich, H., and Girona, T., 2024, Automatic identification and quantification of volcanic hotspots in Alaska using HotLINK - the hotspot learning and identification network: Frontiers in Earth Science v. 12, 1345104. https://doi.org/10.3389/feart.2024.1345104
Full-text PDF 46.1 MB