USGS Volcano Notice - DOI-USGS-HVO-2025-03-25T18:57:39+00:00

Activity Summary:  

Episode 14 of the ongoing Halemaʻumaʻu eruption at Kīlauea's summit ended at 1:49 p.m. HST on March 20 and the eruption is currently paused. Small dome fountains 20-30 feet (5-10 m) high became visible in the north vent from 9:27 am HST to 9:33 am HST. Lava was confined within the cone at this time and is a prelude to the onset of episode 15, which is highly likely to begin today.

Kīlauea's current eruption in Halemaʻumaʻu crater within Kaluapele (the summit caldera) began on December 23, 2024. There have been 14 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.

General Updates: 

The Hawaiian Volcano Observatory and Hawai'i Volcanoes National Park have worked together to install a new webcam (V2cam) at Volcano House with a view from the northeast rim of the caldera toward the west rim. This will provide a live view of the current eruption from a different angle compared to the existing livestream V1 cam. 

Summit Observations:

Episode 14 lasted 28 hours and 23 minutes with the last 7 hours and 19 minutes consisting of fountains up to 600 feet (180 meters) high predominantly from the south vent. Lava flows and fountains stopped erupting from the south vent within Halemaʻumaʻu crater at 1:49 p.m. HST on March 20. Fountains from the north vent ceased 11 minutes earlier. Lava flows from episode 14 covered 75% of the Halemaʻumaʻu crater floor.  The vents continue to degas and glow increased last night, indicating magma remains at shallow levels in the vent. A detailed account of the eruption can be found in the Kīlauea update and the Status Report from March 20.

Deflationary tilt at the summit recorded about 6 microradians lost during this episode using the the Uēkahuna (UWD) tiltmeter. The UWD tiltmeter experienced instrument malfunction on Friday March 21 and is continuing to experience problems. Repair work is scheduled. The Sandhill (SDH) tiltmeter is currently being used to track summit deformation. The SDH tiltmeter has recovered 100% of the tilt lost during episode 14. Seismic tremor decreased significantly at the end of episode 14 but remains above background.

Volcanic gas emissions remain elevated. A maximum sulfur dioxide (SO₂) emission rate measured in the morning on March 20 reached approximately 50,000 t/d. Based on measurements made during earlier episodes and pauses, SO₂ emission rates are likely to be approximately 1,000 t/d during the current pause. An SO₂ emission rate of 1,500 t/d was measured on March 20 at 5:00 p.m. HST.

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 14 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 fit to data derived from past eruptive episodes. The presence of shallow magma in the vents as evidenced by sporadic dome fountains and the rapid rebound of tilt at the end of episode 14 indicate that the eruption will resume. Calculation of the likely time for the start of the next episode has been recalibrated using SDH tiltmeter data. In the last 24 hours, summit inflation surpassed the previous tilt lost in episode 14 and dome fountaining within the north vent began. As a result, the most likely time for the start of episode 15 is today, March 25. This might possibly extend to Wednesday, March 26 if the onset of episode 15 is preceded by prolonged cyclic fountaining confined to the vents. Additional revisions may be necessary if conditions change.

• 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.