Report on Kilauea (United States) — 20 October-26 October 2021
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 20 October-26 October 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, 20 October-26 October 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 the summit eruption at Kilauea continued during 19-26 October at a vent in the lower W wall of Halema`uma`u Crater. Lava entered the lake through a 10-m-wide breach in the E part of the W wall cone, feeding the lake which had risen 49 m since 29 September. Consistent lava fountains from the W vent rose 5-18 m with occasional bursts up to 23 m, based on field crew observations. The sulfur dioxide emission rate was high at 2,600-3,200 tonnes per day during 21-22 and 24-25 October. The lava lake was not level with the deepest parts surrounding the W vent; the W end was 8 m higher than the stagnant E part by 24 October. 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.