Report on Kilauea (United States) — 24 February-2 March 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
24 February-2 March 2021
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2021. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 24 February-2 March 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 a vent on the inner NW wall of Kilauea’s Halema`uma`u Crater continued to supply the lava lake during 24 February-2 March. The depth of the western part of the lake deepened from 217 to 219 m. Lava effused from a submerged vent and rapidly developed a thin crust as it flowed E towards the main stagnant island. The crust occasionally overturned at “plate” boundaries, and lava rarely overflowed onto the sloped margins of the lake. The E half of the lake remained solidified; the crusted area expanded towards the W. The sulfur dioxide emission rate was 700-1,100 tons/day during 25-26 February and 1 March.
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.