USGS Volcano Notice - DOI-USGS-HVO-2024-07-26T17:55:37+00:00

Activity Summary: Kīlauea is not erupting. The Upper East Rift Zone unrest which began on July 22 has ended. The fourth pulse of increased seismicity was over by midday yesterday, and overall seismicity rapidly decreased afterwards and has now returned to ordinary levels. Additional seismic pulses or swarms may occur with little or no warning and result in either intrusion of magma or eruption of lava.

Summit and Upper East Rift Zone Observations: Over the past 24 hours, there were approximately 18 earthquakes detected beneath Kīlauea’s summit, and approximately 300 earthquakes detected beneath the upper East Rift Zone (UERZ), mostly at depths of 0–4 km (0.0–2.5 mi) below the ground surface. Most of these earthquakes are associated with the fourth pulse of intense seismic activity that occurred yesterday morning, related to the UERZ intrusion which started on July 22; only approximately 60 earthquakes occurred within the last 8 hours. The fourth pulse ended by midday yesterday. Most events were smaller than magnitude-2, but there were 4 earthquakes magnitude-3 or higher in the UERZ. Tiltmeters in Kīlauea summit region (instruments SDH, southwest of the summit, and UWE, northwest of the summit) started recording inflating this morning around 3 a.m. H.S.T, suggesting magma is no longer moving into the UERZ. Field crews returned to Chain of Crater Road yesterday afternoon observed new cracks near the intrusion, and more deformation of cracks first observed on July 23. The most recent measurement of the summit's SO₂ emission rate was approximately 65 tonnes per day on July 23, 2024.

Middle and Lower Rift Zone Observations: 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. Measurements from continuous gas monitoring stations downwind of Puʻuʻōʻō in the middle East Rift Zone—the site of 1983–2018 eruptive activity—remain below detection limits for SO₂, indicating that SO₂ emissions from Puʻuʻōʻō are negligible.

Analysis: Recent four strong pulses of earthquake activity from July 22-25, clustered between Pauahi Crater and Maunaulu, represented stages in emplacement of an intrusive dike beneath this area. The intrusion and unrest are now over. The earthquakes and associated local deformation associated with the first three pulses were consistent with satellite data showing formation of a shallow (1-3 km, .5-2 mi) dike in this region. Deformation data was consistent with magma slowly moving out of the storage regions of the summit into the dike; deformation data now indicate this magma movement has ended. The strong pulse of earthquakes yesterday morning was clustered near the intersection of the Chain of Craters and Hilina Pali roads and was not clearly associated with dike formation. Seismic activity greatly decreased after the end of the fourth pulse, and is now back to pre-intrusion levels.

The UERZ intrusion and unrest had more than 1500 detected earthquakes, including 30 earthquakes magnitude-3 or greater.

Additional seismic pulses or swarms may occur with little or no warning and result in either continued intrusion of magma or eruption of lava. 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.

A summary of the first three pulses of intense seismicity activity is provide in an information statement published on July 24: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2024-07-25T02:17:22+00:00, and a summary of the intrusion is provided in a Volcano Watch published yesterday: https://www.usgs.gov/observatories/hvo/news/volcano-watch-whats-been-a-movin-and-a-shakin-kilaueas-upper-east-rift-zone. An interferogram showing recent ground deformation patterns in the UERZ is available here: https://www.usgs.gov/media/images/july-24-2024-insar-image-kilauea-ground-deformation 

Updates: The USGS Hawaiian Volcano Observatory (HVO) will continue to provide daily updates for Kīlauea volcano. Should volcanic activity change significantly, a Volcanic Activity Notice will be issued. HVO is in close contact with Hawai‘i Volcanoes National Park. The Hawai‘i Volcanoes National Park website will have information about any temporary closures: https://www.nps.gov/havo/learn/news/newsreleases.htm 

Recent Eruption Information: Kīlauea erupted briefly on June 3, 2024, southwest of the summit region within a closed area of Hawaiʻi Volcanoes National Park. For more information about this eruption, see this webpage: https://www.usgs.gov/volcanoes/kilauea/science/june-2024-kilauea-southwest-rift-zone-eruption.

Hazards: Shallow magma movement can produce minor to severe ground fractures and subsidence features, which can affect the landscape, human activity, and infrastructure. These ground cracks can continue to widen and offset as magma migration continues, may have unstable overhanging edges, and should be avoided. 

Hazards remain around Kīlauea 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 crater, an area that 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 may continue to widen and offset, may have unstable overhanging edges, and should be avoided. Hazards associated with the recent lava flows include glassy (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 discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards.

The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea Volcano.

Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm.