USGS Volcanoes: Notices released in the last day.

Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. A few small earthquakes were detected in the past day. No activity was observed in mostly cloudy webcam and satellite images over the past day.

The current eruption began in July 2021. Since then, lava flows have filled most of the summit crater and advanced into valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data, webcams, and regional infrasound and lightning networks.

Unrest continues with elevated seismic and infrasound activity. Minor steaming and sulfur dioxide gas emissions from the summit crater were observed in satellite and webcam views over the past day.

Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lightning data, and satellite images to detect eruptions. 

Monitored CALIFORNIA VOLCANOES
Current Volcano Alert Level: all NORMAL
Current Aviation Color Code: all GREEN

Activity Update: All volcanoes monitored by CalVO show normal background earthquake activity and deformation. Monitored volcanoes include Mount Shasta, Medicine Lake Volcano, Lassen Volcanic Center, Clear Lake Volcanic Field, Long Valley Volcanic Region, Coso Volcanic Field, Ubehebe Craters, and Salton Buttes.

Past Week Observations for October 05 (0000h PDT) to October 11 (2359h PDT):

Typical seismicity was recorded at The Geysers geothermal field south of the Clear Lake Volcanic Field; 89 earthquakes greater than M1 were recorded, with the largest having a magnitude of M2.3.

Two earthquakes greater than M1 were recorded in the Sierra Nevada Block, south of Mammoth Mountain and Long Valley, with the largest having a magnitude of M2.2.

Five earthquakes greater than M1 were recorded in the Coso Volcanic Field, with the largest having a magnitude of M2.1.

One earthquake greater than M1 was recorded near the Salton Buttes, with a magnitude of M1.2.

See these notices issued October 7: 

• October 7 Hawaiian Volcano Observatory Status Report summarizing recent intrusive activity and implications: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-10-08T01:00:28+00:00 
• October 7 Hawaiʻi Volcanoes National Park News Release announcing closures related to recent activity: https://www.nps.gov/havo/learn/news/20261007-nr-trail-closures.htm 

Summit Observations:

Just before 11:30 a.m. HST, the north vent began to vigorously dome fountain for nearly an hour feeding a flow that extended almost a kilometer from the vent. This was the longest and most vigorous dome fountain since September 30. There were two other substantial fountain and overflow episodes around 4 p.m. and 7 p.m. HST that lasted for about 40 minutes and 20 minutes respectively. Interspersed between and following these longer events were about 15 smaller events that lasted only a few minutes and produced flows less than 300 feet (100 meters) long. Sustained fountaining was followed by gas jetting often with sprays of spatter produced during drainback of lava within the vents.  The last of these overflow events occurred around 9:30 p.m. HST and only glow with minor gas jetting and spatter were observed from the vents since then. 

Summit tiltmeters showed slight tilt increases over the past 24 hours including at the Uēkahuna tiltmeter (UWD).

In the past 24 hours, there were 20 shallow earthquakes located across the summit region of Kīlauea, predominantly in the south caldera region. GPS stations on opposite sides of Halemaʻumaʻu (CRIM and UWEV) show a small increase in length since the end of September. 

Updated interferometric synthetic aperture radar (InSAR) interferograms following the dike intrusion on September 30-October 1, show the intrusion has been slightly contracting since the evening of October 2. Minor intrusion-related motion was observed along many faults and cracks formed during the 2018 caldera collapse. There are no signs of significant deformation outside the caldera, including the south caldera region.

During inter-episode pauses, the sulfur dioxide (SO₂) emission rate from the summit typically varies between 1,000 and 5,000 tonnes per day. Plumes of volcanic gas are visible from the vents in day-time webcam views.  Winds are currently forecast from the east southeast then changing to from the east this evening.

Rift Zone Observations:

Rates of seismicity and ground deformation remain low in the East Rift Zone and Southwest Rift Zone. SO₂ emissions from the East Rift Zone remain below the detection limit. No significant ground deformation was recorded in either rift zone.

Analysis:

Kīlauea had been erupting episodically between December 23, 2024, and August 25, 2026, from two vents (north and south) in Halema‘uma‘u at the summit. Lava fountaining episodes generally lasted for less than 12 hours and were separated by pauses of two or more weeks. Irregular patterns of ground deformation at Kīlauea summit since the most recent lava fountaining episode, number 54 on August 25, 2026, prevent forecast modeling for when the next fountaining episode can occur. Ground deformation patterns indicate the magma chamber beneath Halemaʻumaʻu is pressurized beyond the level typically seen before recent fountaining events. This pattern was disrupted by the dike intrusion on September 30-October 1 and since then summit tilt has increased slowly with interspersed periods of decreased or flat tilt. The vigorous overflows yesterday indicates that magma remains very near the surface in the established vent complex and continues to be able to generate smaller fountains. It is possible that another fountaining episode from the north-south vent complex could occur; however, intrusive activity underneath Kaluapele is also possible, or magma could exploit existing weak crack systems in the summit region to erupt passively (with little or no seismicity or deformation). 

HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards. Kīlauea volcano alert level and aviation color code remain at WATCH/ORANGE and conditions could change rapidly. For further details, see the recent official notices listed below. 

• October 7 Status Report summarizing recent intrusive activity and implications: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-10-08T01:00:28+00:00 
• October 1 Volcano Watch summarizing recent intrusive activity: https://www.usgs.gov/observatories/hvo/news/volcano-watch-intrusion-during-eruption-summit-kilauea 
• October 1 Status Report published during recent intrusive activity: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-10-01T08:14:21+00:00
• September 15 Status Report on changes in activity and implications for this eruption: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2026-09-15T03:18:09+00:00 
• NOTE: Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages

Hazards:

Eruptive activity since December 2024 has been occurring within a closed area of Hawai'i Volcanoes National Park. However, recent intrusions highlight that the location of eruptive activity could change. Intrusions can also be hazardous with potential to cause earthquakes, ground cracks, and small landslides. The primary hazards at Kīlauea due to eruptive activity and/or intrusions are:

• Volcanic Gas: High levels of volcanic gas—primarily water vapor (H₂O), carbon dioxide (CO₂), and sulfur dioxide (SO₂)—are continually released during an eruption. Emissions can remain locally hazardous in the areas immediately downwind of the vents, even when the vents are not actively erupting. SO₂ reacts in the atmosphere to create vog (volcanic air pollution) downwind. SO₂ and vog may cause respiratory and other problems at high concentrations. Further information on vog can be found at https://vog.ivhhn.org/
• Tephra: Small glassy volcanic fragments—volcanic ash, pumice, scoria, Pele’s hair and reticulite—are created by the lava fountains. A combination of fountaining dynamics and wind conditions determines where tephra fall may occur for any given eruption episode. Larger particles fall near the vents while light particles may be wafted greater distances. These particles may be remobilized during windy conditions following recent eruptive episodes. Residents and visitors should minimize exposure to these fragments, which can cause skin, eye, and respiratory irritation. More information and guidance on tephra fall hazards is available at https://seagrant.soest.hawaii.edu/resource-and-guidance-for-volcanic-tephra-fall/ and https://vog.ivhhn.org/sites/default/files/PelesHair_FAQs_v2.pdf 
• Lava flows: Hawaiian lava flows generally advance slowly downslope but destroy everything in their paths. Lava flows that erupt within Halemaʻumaʻu remain confined to the crater, including those during the eruption that started in December 2024. However, intrusive activity could result in lava flows outside of Halemaʻumaʻu. Hazards associated with active or recent lava flows include hot and glassy (sharp) surfaces that can cause serious burns, abrasions, and lacerations upon contact with unprotected or exposed skin; uneven and rough terrain can lead to falls and other injuries; hot temperatures that can cause heat exhaustion or dehydration, or in heavy rain can produce steamy ground-fog that can be acidic, severely limiting visibility and sometimes causing difficulty breathing.
• Earthquakes and ground cracks: Shallow magma movement and eruptions can produce minor to severe ground fractures and subsidence features. These ground cracks can continue to widen and offset as magma migration continues, may have unstable overhanging edges, and should be avoided. Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes.

Additionally, close to the eruptive vents, the tephra material on the crater rim is prone to cracking, slumping, and small landslides that sometimes expose hot and molten material within. This underscores the extremely hazardous nature of Kīlauea's caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.