Report on Kilauea (United States) — 5 September-11 September 2018
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 5 September-11 September 2018
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2018. Report on Kilauea (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 5 September-11 September 2018. 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 during 5-11 September weak lava activity at Kilauea’s Fissure 8 was characterized by occasional incandescence; during 9-10 September a small collapse pit formed and exposed hot material underneath. Seismicity and ground deformation remain low at the summit, and aftershocks from the M 6.9 earthquake in early May were located along faults on the south flank. The combined rate of sulfur dioxide emission from the summit and the LERZ (<1,000 tonnes/day) were lower than any time since late 2007. A series of small collapses at Pu'u 'O'o Crater during 8-10 September generated visible brown plumes. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange.
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.