Earthquake activity at Kīlauea decreases after brief uptick from previous day

Kīlauea has quieted since yesterday’s uptick in earthquake activity beneath Kaluapele, the volcano’s caldera, and the upper East Rift Zone.

The Hawaiian Volcano Observatory reported this morning that quake counts from the past 24 hours in those two regions decreased by about 65%.

Since yesterday, only about 20 earthquakes were detected beneath the caldera and 30 under the upper East Rift Zone, mostly at depths of up to 1.8 miles. The day before, about 50 were recorded under Kaluapele and 100 beneath the upper East Rift Zone.

All the quakes from the past day were smaller than magnitude 2, with the exception of an magnitude 2.5 and magnitude 2.8 in the upper East Rift Zone.

Despite the uptick a day ago and the continued unrest, the activity is well below the heightened earthquake counts recorded during the June 27-July 1 upper East Rift Zone seismic swarm.

Tiltmeters in the Kīlauea summit region also showed a slight increase in inflationary ground deformation rates during the past day: the SDH instrument southwest of the summit recorded minor inflationary tilt since being re-leveled yesterday and the UWE instrument northwest of the summit qualitatively shows minor inflationary tilt.

GPS instruments around the summit region continue to show longer-term, gradual inflation.

Following the June 3 Southwest Rift Zone eruption, magma has been repressurizing the storage system beneath Halemaʻumaʻu crater and the south caldera region, activating earthquakes in the caldera south of Halemaʻumaʻu and in the upper East Rift Zone.

At this time, it is not possible to say whether this activity will lead to an intrusion or eruption in the near future, or simply continue as seismic unrest.

The volcano’s alert level remains at advisory.

Changes in the character and location of unrest can occur quickly, as can the potential for eruption, but there are no signs of an imminent eruption at this time.

Rates of seismicity and ground deformation beneath the middle and lower East Rift Zone and lower Southwest Rift Zone remain low. Recent eruptive activity and ongoing unrest have been restricted to the summit and upper rift zone regions.

 The Hawaiian Volcano Observatory will continue to provide daily updates for Kīlauea volcano. Should volcanic activity change significantly, a Volcanic activity notice will be issued.