Report on Kilauea (United States) — 15 December-21 December 2021
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 15 December-21 December 2021
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2021. Report on Kilauea (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 15 December-21 December 2021. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
HVO reported that lava effusion continued at a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 14-20 December. The sulfur dioxide emission rate was about 1,400 tonnes per day on 16 December. By 19 December the lake had risen a total of 69 m since the beginning of the eruption. A series of partial overturns of the lake was visible on 20 December, though by the next morning there was no lava effusion from the vent and the lake had crusted over. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Geological Summary. Kilauea overlaps the E flank of the massive Mauna Loa shield volcano in the island of Hawaii. Eruptions are prominent in Polynesian legends; written documentation since 1820 records frequent summit and flank lava flow eruptions interspersed with periods of long-term lava lake activity at Halemaumau crater in the summit caldera until 1924. The 3 x 5 km caldera was formed in several stages about 1,500 years ago and during the 18th century; eruptions have also originated from the lengthy East and Southwest rift zones, which extend to the ocean in both directions. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1,100 years old; 70% of the surface is younger than 600 years. The long-term eruption from the East rift zone between 1983 and 2018 produced lava flows covering more than 100 km2, destroyed hundreds of houses, and added new coastline.