Report on Kilauea (United States) — 17 November-23 November 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
17 November-23 November 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, 17 November-23 November 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 at a vent in the lower W wall of Halema`uma`u Crater. By 16 November the total volume of erupted lava was an estimated 30 million cubic meters, and the lake which had risen a total of 60 m since 29 September. During 17-23 November earthquake activity remained below background levels but volcanic tremor was elevated. Spattering and ponded lava within the vent were visible; lava entered the lake through the E part of the W wall cone, feeding an active area of the lake. Lava periodically oozed from the cooler, outer margins of the lake onto the lowest of the exposed down-dropped caldera floor blocks. The sulfur dioxide emission rate remained above background levels, and was 3,000-3,800 tonnes per day on 18 and 23 November. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Geological Summary. Kilauea, which overlaps the E flank of the massive Mauna Loa shield volcano, has been Hawaii's most active volcano during historical time. Eruptions are prominent in Polynesian legends; written documentation extending back to only 1820 records frequent summit and flank lava flow eruptions that were interspersed with periods of long-term lava lake activity that lasted until 1924 at Halemaumau crater, within the summit caldera. The 3 x 5 km caldera was formed in several stages about 1500 years ago and during the 18th century; eruptions have also originated from the lengthy East and SW rift zones, which extend to the sea on both sides of the volcano. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 km2, destroying nearly 200 houses and adding new coastline to the island.