USGS Volcano Notice - DOI-USGS-HVO-2023-10-09T11:35:48-07:00

Activity Summary: Kīlauea volcano is not erupting. The area just south of Kīlauea's summit is showing signs of unrest. No unusual activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.

Summit Observations: The Kīlauea summit tiltmeter recorded very slight inflation over the past 24 hours. Inflation at the summit of Kīlauea remains at about its highest level in over 5 years and has nearly returned to the level seen just before the last eruption on September 10th. The tiltmeter located just south of the summit is experiencing technical issues that HVO is working to resolve. Elevated seismicity beneath Kīlauea summit region, which began October 4, continues. Over the past 24 hours approximately 125 earthquakes were recorded in Kīlauea summit region compared to about 100 earthquakes occuring over the previous day. Most of the earthquakes from the seismic swarm south of the caldera are at depths of around 2.5–3.5 km (1.5–2 mi) below the surface. The trend of the seismic activity parallels, but is slightly south of the December 1974 eruption vents. Sulfur dioxide (SO2) emission rates remain low and were measured at a rate of about 100 tonnes per day on October 6.

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 downwind of Puʻuʻōʻō in the middle East Rift Zone—the site of 1983–2018 eruptive activity—remain below detection limits for SO₂, indicating that SO₂ emissions from Puʻuʻōʻō are negligible.

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.

The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea volcano.

Next Notice: HVO will issue daily Kīlauea updates. Additional messages will be issued as needed.