HVO reported that two lava lakes at Kilauea were active during 4-10 May. The level of the summit lava lake fluctuated but remained mostly stable deep in the vent inset within the E wall of Halema'uma'u Crater. On 5 May the lava lake level dropped 10-20 m and lava from a vent well above the south side cascaded down into the lake. A gas plume from the vent drifted SW and deposited very small amounts of ash nearby. At Pu'u 'O'o crater, lava from vents near the W edge of the lake and near the base of the E crater wall continued to fill in a perched lava lake in the center of the crater floor. The lake level fluctuated and occasionally overflowed the edges and filled the entire bottom of Pu'u 'O'o crater floor. The crater had infilled about 70 m since the crater floor collapsed in March.

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)