USGS Volcano Notice - DOI-USGS-HVO-2023-06-19T09:49:12-07:00

Activity Summary: Kīlauea volcano is erupting. Eruptive activity is confined to Halemaʻumaʻu crater within the summit caldera at Kīlauea. No unusual activity has been noted along the volcano’s East Rift Zone or Southwest Rift Zone. 

Halemaʻumaʻu Eruption Observations: The eruptive vent on the southwest side of Halemaʻumaʻu continues fountaining and effusing into the lava lake in the far southwestern portion of the crater. The fountain at this vent has been vigorous; yesterday afternoon, a crew of Hawaiian Volcano Observatory geologists estimated that lava was consistently jetting to a height of at least 10 m (33 ft). Deposits from this fountain have further heightened and widened the spatter cone that now sits atop the original eruptive vent in the lower section of the crater wall. Yesterday a single stream of lava was effusing from the base of this cone into the southwestern lava lake, but early this morning a second stream broke off to feed lava onto the southwestern-most block from the 2018 collapse within Halemaʻumaʻu, and both streams are active at this time.

The surface of the southwestern lava lake continues to circulate and is slowly rising, along with the rest of the crater floor, which is uplifting endogenously from lava accumulation below the solidified crust. Lava circulation has been slowing within the central basin that became the focus of effusion during both the 2021–2022 and January–March 2023 eruptions, with its active lava surface shrinking and sitting several meters (yards) below the surrounding crust. Nearly constant overflows from the southwestern lava lake have been cascading into the central basin and accumulating on crusted sections of its floor. No active lava has been observed in the northern or eastern portions of the crater over the past day. A live-stream video of the crater is available at https://www.youtube.com/usgs/live.

Summit Observations: Tiltmeters in the summit region have been tracking steady deflationary tilt since Saturday morning, June 17. Summit seismic activity is dominated by eruptive tremor—a signal resulting from fluid movement, and commonly associated with eruptive activity. Volcanic gas emissions in the area remain elevated; a sulfur dioxide (SO₂) emission rate of approximately 6,300 tonnes per day was measured on Friday, June 16.

Rift Zone Observations: No unusual activity has been noted along the East Rift Zone or Southwest Rift Zone; steady but low rates of ground deformation and seismicity continue along both. Measurements from continuous gas monitoring stations in the middle East Rift Zone—the site of 1983–2018 eruptive activity—remain below detection limits for SO₂.

Hazard Analysis: The eruption at Kīlauea’s summit 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 down-wind. As SO₂ is continuously released from the summit during the 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 lightweight volcanic glass fragments from the lava fountains that will fall downwind of the fissure vents and dust the ground within a few hundred meters (yards) of the vent (s). Strong winds may waft lighter particles to greater distances. Residents and visitors should minimize exposure to these volcanic particles, which can cause skin and eye irritation. 

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 caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007. 

The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea volcano. HVO will continue to issue daily Kīlauea volcano updates until further notice. Additional messages will be issued as needed.