USGS Volcano Notice - DOI-USGS-HVO-2024-02-03T18:13:09+00:00

Activity Summary:  Kīlauea volcano is not erupting. Seismicity in the summit and along the Koa‘e fault system southwest of the summit has decreased significantly over the past 24 hours. The intrusion of magma into this area appears to have slowed, and the likelihood of an eruption has decreased. A VAN/VONA was issued earlier this morning, lowering the Alert level from Orange/Watch to Yellow/Advisory.  

 Summit Observations:  Seismicity and ground deformation beneath the summit and extending 5-7 miles (8-11 km) southwest of the caldera under the Koa‘e fault zone have decreased significantly in the past 24 hours. Earthquake counts have dropped from 20-30 events per hour to 5-10 events per hour and earthquakes are no longer clustering in the vicinity of Pu‘ukoa‘e, but are dispersed more widely from the summit to the southwest. Depths remain consistent, 1–4 km (less than a mile–2.5 mi) below the surface and magnitudes range a maximum of 3+ to less than 1. In total, less than 300 earthquakes have been recorded across this region over the past 24 hours, reflecting the continued decrease in seismicity.   

Over the past day, tiltmeters near Sand Hill and Uēkahuna bluff have recorded very little change after the steep deflation of the past 2 days related to magma moving southwest.   

Global Positioning System (GPS) instruments have recorded up to 8 inches (20 cm) of horizontal motion at stations around the SWRZ and immediately to the south along the Koa‘e fault zone.  

Sulfur dioxide (SO2) gas emission rates remain low. Field measurements indicated an SO2 emission rate of approximately 70 tonnes per day, on January 17, which was similar to measurements in October, November, and early December.     

Patterns of earthquakes and ground deformation indicate that magma intruded beneath the south end of the caldera beginning on the morning of January 27th. This activity waxed and waned until Wednesday, January 31, when greatly increased seismicity and tilt indicated a dike was being emplaced, triggering episodic felt earthquakes and rockfalls within Halema‘uma‘u.  By 5 p.m. HST on January 31st, seismicity migrated southwest of the caldera towards the Ko‘ae fault system and tiltmeters in the south caldera area began to record strong deflation.  Modeling of tiltmeter, GPS, and satellite radar interferometry (INSAR) images suggest that magma within the initial dike migrated southwest into the new intrusion as it opened beneath the Ko‘ae fault zone.  The overall decrease in seismicity and deformation over the past 24 hours suggests that this event is waning.  However, renewed episodes of activity remain a possibility and an eruption could occur with little advanced warning. 

 Rift Zone Observations:  Seismicity in Kīlauea's upper East Rift Zone and Southwest Rift Zone remained low in the past 24 hours.   No unusual activity has been noted along the middle and lower sections of Kīlauea's East Rift Zone. We continue to closely monitor both 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.    

Kīlauea volcano alert level and aviation color code has been lowered to ADVISORY/YELLOW, but the situation remains dynamic. The Hawaiian Volcano Observatory continues to closely monitor Kīlauea volcano and will re-evaluate alert levels and notices as activity warrants.     

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

• This map shows recent earthquake locations: https://www.usgs.gov/media/images/february-2-2024-summary-map-recent-unrest-kilauea-volcano  

• The MITDcam provides views of this area: https://www.usgs.gov/observatories/hvo/mitdcam-kilaueas-upper-southwest-rift-zone-looking-north    

 Please see previously published official notices for more information about recent activity:     

• February 3 Volcanic Activity Notice: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2024-02-03T18:02:36+00:00  

• February 2 daily update: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2024-02-02T20:02:36+00:00   

• February 1 daily update: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2024-02-01T19:44:10+00:00   

• January 31 daily update: https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2024-01-31T10:20:40-08:00   

• January 31 Volcanic Activity Notice:  https://volcanoes.usgs.gov/hans-public/notice/DOI-USGS-HVO-2023-10-06T18:55:23-07:00    

Please note that upgrades to the network are causing intermittent outages that are affecting public access to monitoring data. HVO maintains internal access to volcano monitoring data and will continue to report on volcanic activity.  We apologize for any inconvenience during this dynamic time.    

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.