Kīlaueaʻs summit eruption paused as of at 7:06 a.m. HST on Wednesday, February 26 within Hawaiʻi Volcanoes National Park. A new episode is likely within the next 2-4 days.
Episode 11 of the ongoing Halemaʻumaʻu eruption began at 6:26 p.m. HST on February 25 and fountains reached peak heights of around 600 feet (180 m) 1-2 hours later. The eruption ended on erupting after 12 hours and 40 minutes of activity. Kīlauea's current eruption in Halemaʻumaʻu crater within Kaluapele (the summit caldera) began on December 23, 2024. There have been 11 episodes of lava fountaining separated by pauses in activity. All eruptive activity remains within Hawai'i Volcanoes National Park. No significant 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 south vent within Halemaʻumaʻu crater at about 7:06 a.m. HST on February 26 about 40 minutes after the north vent shut down. Lava flows from episode 11 covered approximately 75%-80% of the Halemaʻumaʻu crater floor.
Last night strong glow was present at both the north and south vents. Lava flows continued to encroach on the eastern side of Halemaʻumaʻu crater floor and onto the downdropped block. Rootless flows fed from beneath the floor of Halemaʻumaʻu crater remained active south of the September 2023 vents. The northeast flow only showed a few spots of incandescence through the night and may be stagnating.
Summit tilt changed rapidly from inflation to deflation at the onset of epidsode 11 (6:26 p.m. HST February 25) and dropped about 10 microradians during the eruption. Tilt turned back to inflation at 6:35 a.m. HST February 26 when fountaining at the north vent stopped. Seismic tremor increased rapidly at the onset of the eruption and decreased sharply when the north vent fountains stopped and returned to the high background levels when the fountaining at the south vent stopped a half an hour later. The Uēkahuna (UWD) tiltmeter has recorded a little over 6 microradians of inflationary tilt since the end of episode 11. Light tremor continues at Kīlauea's summit and there were no earthquakes were located in the summit region in the past 24 hours.
Volcanic gas emissions remain elevated. Based on measurements made during earlier episodes and pauses, sulfur dioxide (SO) emission rates are likely to be approximately 1,000 t/d during the current pause. An SO emission rate of 2,100 t/d was measured at 11 am on February 20.
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.
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 (SO) 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 11 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.
The pressure in the summit magma reservoir has gradually decreased over the first 9 episodes and leveled out during the past two episodes making it possible to calculate the likely start time of the next episode more accurately. Based on the beginning of previous episodes, deflation during the last episode, and current estimates of summit inflation rates, there is a high probability that the start of the next episode will come in the next 2-4 days, between Tuesday March 4 and Thursday March 6th. The probability window may change if there is a significant change in inflation rates during the next week.
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 (HO), carbon dioxide (CO), and sulfur dioxide (SO) -- are the primary hazard of concern, as this hazard can have far-reaching effects downwind. As SO 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.