USGS Volcano Notice - DOI-USGS-HVO-2025-02-05T01:59:15+00:00

Activity Summary:  

The Kīlauea summit eruption paused at 7:23 p.m. HST, on February 4. 

Episode 8 of the ongoing Halemaʻumaʻu eruption ended abruptly at 7:23 p.m. HST on February 4 after about 21.5 hours of eruptive activity. Kīlauea's current eruption in Halemaʻumaʻu crater within Kaluapele (the summit caldera) began on December 23, 2024. There have been 8 episodes of lava fountaining separated by pauses in activity. Earthquake counts remain low beneath the summit and rift zones. All eruptive activity has occurred in Hawai'i Volcanoes National Park. No unusual activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.

Current hazards include volcanic gas emissions and windblown volcanic glass (Pele’s Hair) that may impact Hawai’i Volcanoes National Park and nearby communities.

Summit Observations:

Lava flows and fountains stopped erupting from the north vent within Halemaʻumaʻu crater at about 7:07 p.m. HST on February 4, followed by the south vent at 7:23 p.m. HST. Lava flows from episode 8 covered greater than half of the Halemaʻumaʻu crater floor. Spots of orange glow can still be seen on the crater floor as the erupted lava continues to cool. Glow from the eruptive vents diminished between 1:45 and 3:30 a.m. HST indicating magma is lower in the vent system than during previous pauses. 

Summit tilt changed rapidly from deflation to inflation, and seismic tremor decreased, at about the same time that the lava fountains stopped erupting. The Uēkahuna tiltmeter (UWD) recorded about 11 microradians of deflationary tilt during episode 8 and about 1.3 microradians of inflationary tilt since the end of episode 8. Seismic tremor decreased significantly at the end of episode 8, but remains above background. No significant earthquakes were recorded in the summit region over the past 24 hours. 

Wind conditions did not allow for an SO2 emission rate measurement during episode 8, but emissions were likely around 10,000 t/d or more, based on measurements made during earlier episodes of this eruption. SO2 emissions have now decreased and are likely to be approximately 1,000 t/d during the current pause.

Strands of volcanic glass known as Pele’s Hair have been reported on surfaces throughout the summit area of Hawai’i Volcanoes National Park and surrounding communities. 

• Summit eruption livestream: https://www.youtube.com/usgs/live
• Summit eruption webcams: https://www.usgs.gov/volcanoes/kilauea/summit-webcams 

Rift Zone Observations:

Rates of seismicity and ground deformation remain very low in the East Rift Zone and Southwest Rift Zone with no significant earthquake activity in the past 24 hours. Sulfur dioxide (SO₂) emissions from the East Rift Zone remain below detection limit.

Analysis: 

The current eruption is marked by episodic fountaining not seen in any of the other Halemaʻumaʻu eruptions since 2020. Fountains and lava flows have erupted from two vents that we refer to as the north vent and south vent. The 8 fountaining episodes lasted from a few hours to over a week. Each fountaining episode has been accompanied by strong deflation of the summit region. Pauses between the fountaining episodes have been marked by an immediate change from deflation to inflation as the magma chamber recharges and repressurizes.

Analysis of inflationary tilt patterns prior to the onset of each fountaining episode allows a time window of probability for the onset of new episodes to be estimated. These are calculated using both minimum inflation necessary to start a new eruption and the rate of inflation.

UWD has recorded a net gain of approximately 1.3 microradians of inflationary tilt since the end of episode 8. The rate of inflationary tilt at UWD is currently about 1.5 microradians per day. If this rate continues, preliminary estimates suggest that the most likely window of time for a new episode to begin is 4–8 days from today, February 5. This estimate is based on only 12 hours of tilt data and will be revised in future updates as more data becomes available.

• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information
• Summit eruption reference map: January 15, 2025—Kīlauea summit eruption reference map | U.S. Geological Survey
• Volcano Watch article about Pele's Hair from this eruption: https://www.usgs.gov/observatories/hvo/news/volcano-watch-recent-lava-fountains-highlight-peles-hair-hazards

HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards.

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

Hazards: 

The eruption has been occurring within a closed area of Hawai'i Volcanoes National Park. High levels of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are the primary hazard of concern, as this hazard can have far-reaching effects downwind. As SO2 is continuously released from the summit during an eruption, it will react in the atmosphere to create the visible haze known as vog (volcanic smog) downwind of Kīlauea. Vog information can be found at https://vog.ivhhn.org/.

Additional hazards include Pele's hair and other volcanic fragments from lava fountains. Pele's hair are strands of volcanic glass often produced by lava fountaining activity. Volcanic fragments can fall on the ground within a few hundred yards (meters) of the eruptive vent(s), or on the western caldera rim downwind of the vent(s). Strong winds may waft light particles to greater distances downwind. Once they are on the ground, they can sometimes cluster and tangle together giving it the appearance of a tumbleweed. The extent of Pele's hair is dependent on lava fountaining activity and current wind conditions.  Residents and visitors should minimize exposure to these volcanic particles, which can cause skin and eye irritation. More information about how Pele's hair is formed is available here: https://www.usgs.gov/observatories/hvo/news/volcano-watch-peles-hairs-a-beautiful-hazard-island-hawaii. A Frequently Asked Questions document developed for the 2022 Mauna Loa eruption includes information about potential health effects of Pele's hair and is available here: https://vog.ivhhn.org/sites/default/files/FAQ_on_air_quality_and_health_during_Mauna_Loa_eruption_v1.6.pdf

Hawaiian lava flows generally advance slowly downslope, and during this eruption flows have been confined to Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea's summit caldera. 

Other significant hazards also 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 Kīlauea's caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.

For discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards.