HVO reported that lava in the deep pit within Kilauea's Halema'uma'u crater was visible on 5 April and rose, fell, and circulated within the pit during 6-12 April. At Pu'u 'O'o crater, the level of the lava lake fluctuated, and was fed from a source in the central portion of the lake. During 5-8 April a gas plume from the vent deposited very small amounts of ash nearby, derived from rockfalls and occasional lake spatter.

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)