A new eruption at Kilauea began at 0444 on 7 June with the burst of tall lava fountains from a vent on the central part of the Halema’uma’u Crater floor. The Volcano Alert Level was raised to Warning (the highest level on a four-level scale) and the Aviation Color Code was raised to Red (the highest level on a four-color scale). Soon after, lava fountains were active along multiple fissures on the crater floor, and along one fissure that bisected the SW crater wall. Between 0800-0900 the sulfur dioxide emission rate was about 65,000 tonnes per day. Residents of Pahala, 30 km downwind of the summit, reported minor deposits of fine gritty ash and Pele?s hair. Lava flows inundated the crater floor (about 1.5 square km) and added about 6 m depth of new lava within a few hours. A small spatter cone had formed at the vent on the SW wall by midday, and lava from the cone was flowing into the active lava lake below. Fountain heights had decreased from the onset of the eruption and were 4-9 m high by 1600, with occasional higher bursts. Inflation switched to deflation and summit earthquake activity greatly diminished shortly after the eruption onset.

At 0837 on 8 June HVO lowered the Volcano Alert Level to Watch and the Aviation Color Code to Orange because the initial high effusion rates had declined, and no infrastructure was threatened. The lava lake had dropped by about 2 m likely due to gas loss by the morning of 8 June. The drop left a wall of cooled lava around the margins of the crater floor. Multiple lava fountains were active in the central E part of the lake and fountains rose as high as 10 m. The spatter cone continued to build over the SW wall vent; lava flows from the vent fed the SW part of the lava lake. The preliminary average effusion rate for the first 24 hours of the eruption was about 150 cubic meters per second, though the estimate did not account for vesiculated lava and variations in crater floor topography. The effusion rate during the very earliest phases of the eruption appeared to be significantly higher than the previous three summit eruptions based upon the rapid coverage of the entire crater floor.

During 8-9 June multiple lava fountains remained active and rose up to 10 m high. The SW wall vent continued to effuse lava into the crater lake which had increased in depth by about 1.5 m. Active lava and vents covered much of the W half of the crater floor, arranged in a broad horseshoe shape around a central uplifted area. This feature in the basin of the 2021-22 lava lake was described as the "western lava lake" from prior eruptions and had reactivated along with a smaller circular pool just SE of the lake. An active lava lake centered within the uplifted area was fed by a vent in its NE corner. A much smaller area of lava was active in the E portion of the crater floor. The sulfur dioxide emission rate was about 11,000 tonnes per day on 9 June and about 8,900 tonnes per day on 10 June.

During 10-12 June multiple lava fountains remained active and were up to 9 m high, and the SW wall vent continued to effuse lava into the crater lake. The active features in the E portion of the lake had stagnated during 10-11 June. Sulfur dioxide emissions averaged 7,400 tonnes per day on 11 June. The W part of the lake rose about 1 m during 11-12 June, likely due to the construction of a levee around the pond. Gas plumes rose to 2.4-3 km (8,000-10,000 ft) a.s.l. and were trapped under a weather inversion layer. Activity decreased during 12-13 June and only a few small lava fountains were active. The western lake and the smaller lava pond in the central portion of the crater floor remained active, along with the vent on the SW wall.

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.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)