USGS Volcano Notice - DOI-USGS-HVO-2025-03-05T19:44:42+00:00

Activity Summary: 

Episode 12 of the Halemaʻumaʻu eruption of Kīlauea within Hawaiʻi Volcanoes National Park ended at 10:37 a.m. HST on March 5 after just under 22 hours of continuous eruptive activity. Fountaining from the south vent ceased at 10:35 a.m. at the same time summit deflation changed to inflation and tremor decreased. Current hazards include volcanic gas emissions and windblown volcanic glass (Pele’s Hair) that may impact Hawai’i Volcanoes National Park and nearby communities. 

Episode 12 began yesterday, March 4, when small, intermittent flows first erupted at 7:30 a.m. and 9:33 a.m., followed by continuous eruption of sluggish flows at 12:45 p.m. Lava fountaining began at 2:00 p.m. Fountains reached heights of 600 feet (180 meters) by 3:00 p.m. These heights were sustained until the north vent quit erupting at 8:26 p.m. Sustained fountains from the south vent continued overnight with heights of 200-400 feet (60-120 meters) before decreasing this morning, March 5, after 5:00 a.m. Fountaining from the south vent increased again around 8:00 a.m., and the north vent briefly resumed fountaining and erupting lava flows from 8:42 to 9:11 a.m., before both vents quit erupting after 10:30 a.m. Lava flows from this episode covered over two thirds of the floor of Halemaʻumaʻu within the southern part of Kaluapele (Kīlauea caldera). 

SO2 emission rates were averaging approximately 35,000 tonnes per day (t/d) during the period of high fountaining yesterday afternoon, March 4, but were down to around 20,000 t/d this morning during lower fountaining. SO2 emission rates during the pause period are estimated to be about 1,000 tones per day, similar to those measured during other pauses in this ongoing eruption.

Summit tiltmeters recorded about 11 microradians of deflation during episode 12. The end of fountaining at 10:35 a.m. was coincident with a rapid change from summit deflation to inflation and a decrease in seismic tremor intensity.  

This was the 12th episode of Kīlauea's ongoing eruption in Halemaʻumaʻu crater within Kaluapele that began on December 23, 2024. Eruptive episides have lasted from 12 hours to 8 days. Episodes have been separated by pauses in eruptive activity lasting less than 24 hours to 12 days.

• Timeline of eruptive episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information 
• The Kīlauea summit livestream video is available here: https://www.youtube.com/usgs/live  

All eruptive activity is occurring in Hawai'i Volcanoes National Park. No changes have been detected in the East Rift Zone or Southwest Rift Zone. HVO continues to closely monitor Kīlauea and will issue an eruption update tomorrow morning unless there are significant changes before then. 

Kīlauea Volcano Alert Level/Aviation Color Code remain at WATCH/ORANGE. All current and recent activity is within Hawaiʻi Volcanoes National Park.

Hazards: 

This episodic eruption is 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 that can fall on the ground downwind of the eruptive vent(s). Pele's hair are strands of volcanic glass often produced by lava fountaining activity. Strong winds may waft these light particles to greater distances downwind. Pele's hair can sometimes cluster and tangle together on the ground, 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 and the southwest side of Kaluapele, Kīlauea's summit caldera. 

Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu 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, an area that has been closed to the public since late 2007.