Hawaiian Volcano Update: Another Round of Kīlauea South Caldera Quakes
Less than 3 weeks following its most recent summit eruption, Kīlauea is showing signs of unrest through an earthquake swarm and elevated ground tilt near the south caldera once again. This suggests magma recharge has been ongoing, and has quickly resumed building pressure in the summit reservoir. It appears the build-up to the next eruption has begun, once again contained to the volcano's summit with no unusual activity along either rift zone or near populated areas. Given the quick resumption and escalation of earthquakes, the USGS Hawaiian Volcano Observatory today resumed its daily Kīlauea updates. This same area of activity saw numerous swarms starting about 3 weeks before the September 10 to 16, 2023 eruption, along with localized inflation most evident east of the Sand Hill tilt station about 2 weeks prior. The similar ground tilt signal this past week, totaling a significant 30 microradians, began to level off coincident with the earthquake swarm, however, a slightly different pattern than before. Back in August 2021, an intrusion in this area recorded a similar levelling off in each of its two stages. It remains to be seen whether the current pattern of intrusion will continue, and whether it resumes its progress towards an eruption.
Gas emissions remain at background levels for the volcano around 150 tonnes of SO2 per day, but can still affect sensitive individuals in downwind areas.
Maunaloa is still quiet, with two deep earthquakes over the past week, and expected inflation showing recharge following its 2022 eruption. Following the 1984 eruption, a similar period of inflation without earthquakes lasted about 10 years. Any sign of renewed activity of Maunaloa will eventually occur in the context of this post-eruptive background trend.
We present monitoring data, imagery and reports courtesy of the USGS Hawaiian Volcano Observatory to explain the newest unrest, annotating our presentation on-screen and discussing live viewer questions as we go.
