Kīlauea - Volcano Updates
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Monday, December 6, 2021, 10:40 AM HST (Monday, December 6, 2021, 20:40 UTC)
KILAUEA VOLCANO (VNUM #332010)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary: Kīlauea volcano has been erupting from a single vent in the western wall of Halemaʻumaʻu crater. As of this morning, December 6, 2021, the eruption appears to have been paused for at least the past day and activity is difficult to view given the current weather. All recent lava activity has been confined within Halemaʻumaʻu crater in Hawai‘i Volcanoes National Park.
Summit Observations: Lava effusion from the western vent decreased significantly Friday afternoon, accompanied by a dramatic decrease in volcanic tremor. Both remain low this morning. Deflation bottomed out around noon on Saturday, December 4 and the summit began re-inflating at about 7 AM on Sunday. Inflation continued over the next 21 hours, peaking at 4 AM this morning. Volcanic tremor measurements have been erratic over the past 24 hours due to wind and rain, but are substantially lower than values prior to the pause. The most recent measurement of Sulfur dioxide (SO2) emission rates on November 29, 2021 was approximately 1200 tonnes per day obtained. However, continuous instrument measurements indicate that SO2 emission rates have decreased with the change in eruption rate. Earthquake activity remains below background.
Halemaʻumaʻu Lava Lake Observations: Lava had been erupting from a single vent in the western wall of Halemaʻumaʻu crater, while the eastern edge of the lake has advanced onto the lowest of the exposed down-dropped caldera floor blocks. Friday afternoon, the rate of lava effusion from the western vent decreased sharply. There has been no observable surface activity for the past two days and thermal camera images, when visible, show only a few small hotspots around the vent area. All of the instrumental data and observations indicate the eruption is paused. This is the fourth and largest such slow down or pause since the eruption began on September 29 and none of the prior events lasted more than 24 hours before resumption of normal eruptive activity. Summit re-inflation has recovered most of the tilt lost during the deflationary event, but tremor levels remain well below previous levels recorded during eruptive activity. It is possible that some lava may be entering the lake beneath the crust, but the laser range finder used to measure crustal uplift has been incapacitated by the weather. The western end of the lake has shown little change in maximum elevation over the prior several days, with HVO’s permanent laser rangefinder showing an elevation of approximately 809 meters (2654 ft) when a measurement was last possible on Friday. The lake has seen a total increase of about 65 meters (213 ft) since lava emerged on September 29. Webcams have shown spatter and ponded lava within the west vent, an area of active lava at the surface of the lava lake, and sporadic oozes of lava along the cooler outer lake margins. The total erupted volume since the beginning of the eruption was estimated to be about 30 million cubic meters (7.8 billion gallons) on November 16.
East Rift Zone Observations: No unusual activity has been noted in the Kīlauea East Rift Zone. Low rates of ground deformation and seismicity continue along the rift zones. SO2 and hydrogen sulfide (H2S) emissions from Puʻuʻōʻō were below instrumental detection levels when last measured on January 7, 2021.
Hazard Analysis: This new eruption at Kīlauea’s summit is occurring within a closed area of Hawai'i Volcanoes National Park. Therefore, high levels of volcanic gas are the primary hazard of concern, as this hazard can have far-reaching effects down-wind. Large amounts of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are continuously released during eruptions of Kīlauea Volcano. As SO2 is released from the summit, it reacts in the atmosphere to create the visible haze known as vog (volcanic smog) that has been observed downwind of Kīlauea. Vog creates the potential for airborne health hazards to residents and visitors, damages agricultural crops and other plants, and affects livestock. For more information on gas hazards at the summit of Kīlauea, please see: https://pubs.er.usgs.gov/publication/fs20173017. Vog information can be found at https://vog.ivhhn.org/.
Additional hazards include Pele's hair and other lightweight volcanic glass fragments from the lava fountains that will fall downwind of the fissure vents and dust the ground within a few hundred meters (yards) of the vent (s). Strong winds may waft lighter particles to greater distances. Residents should minimize exposure to these volcanic particles, which can cause skin and eye irritation.
Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of Kīlauea caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since early 2008.
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. Visitors to Hawai'i Volcanoes National Park should note that under southerly (non-trade) wind conditions, there is potential for a dusting of powdery to gritty ash composed of volcanic glass and rock fragments. These ashfalls represent a minor hazard, but visitors should be aware that dustings of ash at areas around the Kīlauea summit are possible.
The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea Volcano.
HVO will continue to issue daily Kīlauea Volcano updates until further notice. Additional messages will be issued as needed.
Kīlauea activity summary also available by phone: (808) 967-8862
Kīlauea webcam images: https://www.usgs.gov/volcanoes/kilauea/webcams
Kīlauea photos/video: https://www.usgs.gov/volcanoes/kilauea/photo-video-chronology
Kīlauea lava-flow maps: https://www.usgs.gov/volcanoes/kilauea/maps
Kīlauea FAQs: https://www.usgs.gov/volcanoes/kilauea/faqs
Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
Summary of volcanic hazards from eruptions: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards
Recent earthquakes in Hawaiʻi (map and list): https://www.usgs.gov/observatories/hawaiian-volcano-observatory/earthquakes
Explanation of Volcano Alert Levels and Aviation Color Codes: https://www.usgs.gov/natural-hazards/volcano-hazards/about-alert-levels
The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawaiʻi.