USGS Volcano Notice - DOI-USGS-HVO-2023-12-07T09:00:21-08:00

Activity Summary:  Kīlauea volcano is not erupting. Last night saw moderate seismicity in the summit region, with continued low-level seismic activity in the upper East Rift Zone and Southwest Rift Zone over the past day. Unrest may continue to wax and wane with fluctuating input of magma to the area, and eruptive activity could occur in the near future with little or no warning. No unusual activity has been noted along the middle and lower sections of Kīlauea’s East Rift Zone.

Summit Observations:  Summit seismicity experienced a slight uptick last night, focused in the area south of Kīlauea's summit caldera. This followed several days of relatively low seismicity, but activity did not reach the levels seen during an earthquake swarm on December 2, nor the levels that immediately preceded recent summit eruptions. A M4.4 earthquake occurred east-northeast of the summit at 5:17 p.m. HST yesterday at a depth of 14 mi (23 km), and a M3.6 earthquake occurred east-northeast of Pāhala at 7:13 a.m. HST today at a depth of 21 mi (33 km); neither of these earthquakes are believed to be directly related to near-surface volcanic activity, and no associated changes were observed at Kīlauea.

The Uēkahuna summit tiltmeter—located northwest of the caldera—tracked steady inflationary tilt until around midnight last night, when there was a quick transition to deflationary tilt. Despite a brief interruption between 5:00 a.m. and 7:00 a.m. HST this morning, the deflationary trend continues at this time. The Sand Hill tiltmeter—located southwest of the caldera—has tracked similar trends. Overall, the summit of Kīlauea remains at a high level of inflation; relative tilt is above the level reached prior to the most recent eruption in September 2023, and it is higher than at any time since the 2018 eruption.

Sulfur dioxide (SO₂) gas emission rates remain low. Field measurements indicated an SO₂ emission rate of approximately 70 tonnes per day on December 5, which was similar to measurements in October and November.

There are currently no signs of an imminent eruption, but the summit region remains unsettled, with a high level of inflation and moderate seismic activity. The onsets of previous summit eruptions have been marked by strong swarms of earthquakes caused by the emplacement of a dike 1–2 hours before the appearance of lava, and these swarms are not being detected at this time.

The HVO information statement released on October 23, 2023, provides additional information and context related to recent unrest at Kīlauea's summit: https://volcanoes.usgs.gov/hans2/view/notice/DOI-USGS-HVO-2023-10-23T22:33:18-07:00

A map summarizing recent unrest southwest of Kilauea’s summit (activity beginning October 4, 2023) can be found here: https://www.usgs.gov/maps/november-5-2023-summary-map-intrusive-activity-kilauea-volcano

Rift Zone Observations:  Small earthquakes (less than M2.0) have continued to occur in the upper East Rift Zone following a swarm early on December 2, with steady activity over the past day. Earthquakes continue in the Southwest Rift Zone as well, but at a diminished rate compared to a few weeks ago.

We continue to closely monitor both rift zones, especially near the summit. No unusual activity has been noted along the middle and lower East Rift Zones. Measurements from continuous gas monitoring stations downwind of Puʻuʻōʻō in the middle East Rift Zone—the site of 1983–2018 eruptive activity—have been below detection limits for SO₂, indicating that SO₂ emissions from Puʻuʻōʻō are negligible.

Hazard Analysis:  Levels of volcanic gases (sulfur dioxide and carbon dioxide) can remain locally hazardous even when Kīlauea is not erupting. Local concentrations of sulfur dioxide (SO₂) and/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.