Kīlauea Update: Earthquake Swarm has Waned

Kīlauea Volcano is not erupting, and it does not appear it will in the immediate future.

The earthquake swarm that began beneath the south part of Kīlauea caldera, within Hawaiʻi Volcanoes National Park, on Aug. 23, 2021, has waned.

Within the past 24 hours, only 10 earthquakes have been detected in this area. The earthquake swarm began in that region at around 4:30 pm on Aug. 23 and continued until the morning of Aug. 25, 2021. A total of 478 earthquakes were detected during this swarm; the rate of earthquakes detected per hour peaked at 28 events between 7 and 8 pm HST on Aug. 24. Most of the earthquakes were between magnitude 1 and 2 and occurred approximately 1-2 km (0.6-1.2 mi) below the Earth’s surface.

The earthquake swarm was accompanied by change in the rate and style of ground deformation. Ground deformation in the Kīlauea summit region has leveled off within the past 24 hours and rapid inflation near the region of Kīlauea’s south caldera is no longer being observed.

Earthquake activity and ground deformation have decreased together to levels that indicate magma is no longer moving into the region of Kīlauea’s south caldera. These changes indicate reduced potential for an eruption at this time.

Kīlauea summit sulfur dioxide (SO2) emission rates remain at very low levels that have persisted since May 2021, when the most recent summit eruption ended. Concentrations of SO2 in ambient air, measured at stations in the Kīlauea summit region, show no changes. The most recent SO2 emission rates, measured on Aug. 12, were 50 tonnes per day, close to levels associated with the non-eruptive period from late 2018 to late 2020 (less than 50 tonnes per day). This is significantly lower than emission rates that averaged over 800 tonnes per day from mid-February to mid-April when the summit eruption of Kīlauea was ongoing.

HVO scientists will continue to monitor Kīlauea volcano closely and will issue additional messages as warranted by changing activity.

Stay informed about Kīlauea by following volcano updates and tracking current monitoring data on the HVO web page (https://www.usgs.gov/volcanoes/kilauea/volcano-updates) or by signing up to receive updates by email at this site: https://volcanoes.usgs.gov/vns2/.