During 23-29 July HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema`uma`u Crater. Gas emissions remained elevated. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas; smaller particles may have been dropped several kilometers away. On 24 July a small explosion triggered by rockfalls from the southeast crater wall sent spatter onto the closed tourist overlook at Halema`uma`u; small rockfalls also disturbed the lava lake surface on 27 July.

Lava flows fed from a vent on Pu`u `O`o's northeast flank continued to advance slowly NE as two lobes that reached 2.4 km from the vent on 25 July. Lava was at or near the surface within the four pits on the crater floor and a small lava flow erupted from the southern pit during the night of 25-26 July. On 28 July there were a few small collapses around the edge of Pu`u `O`o's crater.

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)