USGS Volcano Notice - DOI-USGS-HVO-2021-10-04T11:38:35-07:00

HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Monday, October 4, 2021, 8:42 AM HST (Monday, October 4, 2021, 18:42 UTC)

KILAUEA VOLCANO (VNUM #332010)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED

Activity Summary: Kīlauea volcano is erupting. Lava continues to erupt from multiple vents along the floor and western wall of Halemaʻumaʻu crater. As of this morning, October 4, 2021, all lava activity is confined within Halemaʻumaʻu in Hawai‘i Volcanoes National Park. Seismicity and volcanic gas emission rates remain elevated.

Summit Observations:  Sulfur dioxide (SO2) emission rates remain high and were measured as approximately 14,750 tonnes per day on October 2, 2021. These rates are higher than measured on the previous day, but significantly lower than the initial emission rates of 85,000 tonnes per day that were measured just after the eruption started on the afternoon of September 29, 2021. Seismicity is elevated but stable. Summit tiltmeters continue to record deflationary tilt.

Halemaʻumaʻu Lava Lake Observations: Lava continues to erupt from multiple vents within Halemaʻumaʻu. Over the past 24 hours, the lava lake level has risen approximately 2 meters (6.6 ft). The west vent continues to be the most vigorous source, with sustained lava fountain heights of 10-15 meters (33-49 ft), but up to 20 meters (66 ft). The lava lake has risen to the base of the west vent, around which a 12-meter-high (40 ft) spatter rampart is being built. Other vents—including a 35-42-meter-long (115-138 ft) fissure—continue to be active in the central and southern parts of the lake, with sustained lava fountain heights of 5-10 meters (16-33 ft). Due to the location of vents, the lava lake is not level across its surface; areas closer to vents are higher in elevation. Yesterday evening, the west end of the lake was approximately 1-2 meters (3.3-6.6 ft) higher than the east end, and the south end was approximately 2-3 meters (6.6-9.8 ft) higher than the north end. The north and east boundaries of the lava lake are separated from Halemaʻumaʻu crater wall by narrow ledges, approximately 20-meters wide (66 ft), that are lower in elevation than the active portion of the lava lake surface; the north, east, and south sides of the lava lake are perched several meters (approximately 10 ft) above this surrounding ledge. Localized and discontinuous crustal foundering continues (a process by which cool lava crust on the surface of the lava lake is overridden by less-dense liquid from below causing the crust to sink into the underlying lake lava).

East Rift Zone Observations: No unusual activity has been noted in the Kīlauea East Rift Zone. Ground deformation motion suggests that the upper East Rift Zone—between the summit and Puʻuʻōʻo—has been steadily refilling with magma over the past year. 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 late 2007. 

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.

More Information:
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

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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

CONTACT INFORMATION:

askHVO@usgs.gov

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.