Slow lava eruption continues at Great Sitkin volcano, Alaska

The Alaska Volcano Observatory reported a continuous slow eruption of lava in the summit crater of Great Sitkin Volcano as of 19:30 UTC on January 30, 2024. The Aviation Color Code remains at Orange and Alert Level at Watch.

The Alaska Volcano Observatory (AVO) reported a steady eruption of lava in the summit crater of Great Sitkin Volcano, ongoing as of 19:30 UTC on January 30, 2024. The Volcano Alert Level remains at Watch, the third highest level on a four-level scale, and the Aviation Color Code stays at Orange, indicating continued volcanic activity.

Over the past day, infrequent and small volcanic earthquakes were detected. However, due to mostly cloudy conditions, no significant activity was observed in satellite or web camera imagery.

AVO noted that the lava effusion at Great Sitkin’s summit lava dome continued from January 16 to 23, with the lava flow concentrated at the center of the dome. This activity was confirmed through radar images and identified weakly elevated surface temperatures in satellite data from January 16 to 18. However, local webcams and seismic data communications were disrupted due to a storm-related power failure.

The ongoing lava flow at Great Sitkin began erupting in July 2021. There have been no explosive events since a single eruption on May 25, 2021, which produced an ash plume rising to approximately 4.6 km (15 100 feet). Witnesses located about 42 km (26 miles) away reported hearing a loud explosion during this event.

Monitoring efforts for Great Sitkin include local seismic and infrasound sensors, web cameras, regional infrasound and lightning networks, and satellite data.

The volcano, part of the Aleutian Islands, is located within a UNESCO Biosphere Reserve property. Great Sitkin Island is dominated by the volcano, which has a complex history including a massive edifice failure, debris avalanches, and the formation of a younger parasitic volcano with a small summit caldera. Historical eruptions at Great Sitkin have been recorded since the late-19^th century, making it a significant geological feature in the region.

References:

¹ ALASKA VOLCANO OBSERVATORY DAILY UPDATE – USGS – Tuesday, January 30, 2024, 19:30 UTC)

² Global Volcanism Program, 2024. Report on Great Sitkin (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 17 January-23 January 2024. Smithsonian Institution and US Geological Survey.

³ Great Sitkin – Geological summary – GVP

Featured image: Great Sitkin volcano on January 18, 2024. Credit: Copernicus EU/Sentinel-2, The Watchers