USGS Volcano Notice - DOI-USGS-HVO-2023-09-19T11:18:56-07:00

Activity Summary: Kīlauea volcano is not erupting. No significant changes have been observed at the summit or in either rift zone since the summit eruption that began on September 10 ended on September 16.  Future eruptions at Kīlauea's summit remain possible and HVO continues to monitor activity. HVO will issue weekly Kīlauea updates on Tuesdays until further notice.

Summit Observations: Overnight webcam views showed sparse incandescent spots as lava erupted over the past week continues to cool on the downdropped block and Halemaʻumaʻu in Kīlauea's summit caldera. It is unlikely that the recent eruption will resume based on the behavior of past, short-lived summit fissure eruptions at Kīlauea summit in 1982, 1975, 1974, and 1971, which all ended abruptly. Summit seismicity has remained low, with very few earthquakes over the past week, and tremor is at background levels following eruptive activity stopping on September 16. Summit tiltmeters recorded deflation as the eruption waned towards the end of last week. After several days of inflation, deflationary tilt has returned with little net deformation at the summit over the past week. Sulfur dioxide (SO2) emissions have decreased to near background levels and were measured at a rate of 200 tonnes per day on September 17. Information on the recent Kīlauea summit eruption is available at: https://www.usgs.gov/volcanoes/kilauea/recent-eruption. 

Rift Zone Observations: No unusual activity has been noted along the East Rift Zone or Southwest Rift Zone; steady rates of ground deformation and seismicity continue along both. Measurements from continuous gas monitoring stations on the middle East Rift Zone remain below detection limits for SO₂.

Hazard Analysis: Levels of volcanic gas (sulfur dioxide and carbon dioxide) can remain locally hazardous even though Kīlauea is no longer erupting. Sulfur dioxide (SO₂) gas emissions have greatly decreased; however, local concentrations of sulfur dioxide (SO₂) or hydrogen sulfide (H₂S) may persist in downwind areas, and residents may notice odors of these gases occasionally. Significant hazards also remain around Halemaʻumaʻu from crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. For discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards.
 
Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm. 
 
The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea Volcano. 

Next Notice: HVO will issue weekly Kīlauea updates on Tuesdays until further notice. Additional messages will be issued as needed.