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Number of quakes doubles during past day beneath Kīlauea as unrest continues

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Panoramic U.S. Geological Survey webcam view from 8:50 a.m. Tuesday of Halemaʻumaʻu crater and the down-dropped caldera floor from the west rim of the Kīlauea summit caldera, looking east.

Unrest continues to rattle Kīlauea, with the number of earthquakes recorded during the past day doubling beneath Kaluapele, the volcano’s caldera, and its upper East Rift Zone.

Since Monday, there were about 50 earthquakes detected beneath Kaluapele and 100 beneath the upper East Rift Zone, mostly at depths of 0.6 to 1.8 miles, more than double from the previous day in some cases.

That’s compared with 20 quakes beneath the summit and 50 beneath the upper East Rift Zone the day before.

Most were smaller than magnitude 2; however, there were several between magnitude 2 and 3, and one magnitude 3 quake beneath the upper East Rift Zone.

Tiltmeters in Kīlauea summit region also show a slight increase in inflationary ground deformation rates during the past day.

That’s the latest from the Hawaiian Volcano Observatory at 8:37 a.m. Tuesday. The volcano’s alert level remains at Advisory.

No eruption is happening. There are no signs of an imminent eruption.

It is not possible to say if the ongoing activity will lead to an intrusion of magma or eruption in the near future. Changes in the character and location of the unrest can happen quickly — as can the potential for eruption.

In fact, despite the doubling of quake counts during the past 24 hours, the numbers and activity remain well below those seen during the June 27 to July 1 upper East Rift Zone swarm.

This map shows recent deformation at Kīlauea, from June 6 to July 8. Data was recorded by the Italian Space Agency’s (ASI) Cosmo-SkyMED satellite. Colored fringes denote areas of ground deformation, with more fringes indicating more deformation. Each color cycle represents 0.6 of an inch of ground motion. The bulls-eye feature indicates inflation of the area southwest of Kaluapele, the volcano’s summit, during this time period. The northeast-southwest trending line-like feature reflects the intrusion (body of magma underground) that fed the June 3 eruption in the Southwest Rift Zone. Arrow in the upper left indicates satellite orbit direction and look direction (bar). For information about interpreting interferograms, see this “Volcano Watch” article: “Reading the rainbow: How to interpret an interferogram.” (Courtesy of the Hawaiian Volcano Observatory)

Longer-term, gradual inflation of the summit and upper rift zones has persisted, however, since the end of the June 3 Southwest Rift Zone eruption.

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 as magma continues to repressurize the storage system beneath Halemaʻumaʻu and the south caldera region following the June 3 eruption.

The Hawaiian Volcano Observatory will continue to provide daily Kīlauea updates. Should activity change significantly, the public will be notified.

While the volcano is not erupting, hazards remain around the caldera from Halemaʻumaʻu crater wall instability, ground cracking and rockfalls that can be enhanced by earthquakes within the area closed to the public.

This underscores the extremely hazardous nature of the rim surrounding Halemaʻumaʻu, which has been closed to the public since early 2008.

Near the recent Southwest Rift Zone eruption site, minor to severe ground fractures and subsidence features could continue to widen and offset, might have unstable overhanging edges and should be avoided.

Hazards associated with the recent lava flows include glassy and sharp surfaces that can cause serious abrasions and lacerations upon contact with unprotected or exposed skin, uneven and rough terrain that can lead to falls and other injuries or locally elevated levels of volcanic gases that can lead to breathing difficulty.

For more information about Kīlauea hazards, click here.


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