The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea’s Kaluapele summit caldera, from two vents along the SW margin of Halema’uma’u Crater, continued at variable levels during 22 April-6 May. Incandescence at the S vent was visible during 22-25 April, then at both the N and S vents during 26 April-1 May. Weak spattering at the N vent was visible just before 1850 on 27 April. A tiny lava pool at the S vent was visible overnight during 29-30 April. Spattering at the N vent was visible along with flames from hydrogen gas burning in air during 29 April-1 May. Sulfur dioxide emissions averaged 1,350 tonnes per day (t/d) on 30 April, typical levels during periods with no lava fountains.

At the N vent, cycles of dome fountaining, short lava overflows, and lava immediately draining back into the vent began at around 1149 on 1 May and lasted above nine hours. There were 26 cycles, with each lasting 10-15 minutes separated by about 10 minutes of repose. The activity intensified at around 1845. Lava fountains became sustained at 2128 and rose up to 100 m. Fountaining lasted for seven hours and 52 minutes, ceasing at 0520 on 2 May. Lava flows covered about half of the crater floor. Sulfur dioxide emissions averaged 1,750 t/d later that same day. Incandescence at both vents was visible overnight during 3-5 May. Occasional spattering at the N vent was visible during 4-5 May. Activity increased on 5 May. During 1049-1800 there were about 30 cycles of dome fountaining and lava draining back into the N vent. Lava overflowed the vent rim several times producing short lava flows. At 1123 a short lava flow from the S vent advanced onto the crater floor. Incandescence from both vents was visible overnight during 5-6 May. Lava fountaining at the N vent began at 1728 on 6 May and fountains quickly rose at least 150 m. Fast-moving lava flows traveled across the crater floor. Fountains also rose from the S vent as high as 20 m. Fast-moving lava flows from mainly the N vent and somewhat from the S vent traveled across the crater floor, covering less than half of it. Activity ceased at 2158. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

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)