During 10-16 April HVO reported that the circulating lava lake periodically rose and fell in the deep pit within Kīlauea's Halemaʻumaʻu Crater. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas.

At Puʻu ʻŌʻō Crater, glow emanated from four spatter cones on the crater floor. Two lava flows (Peace Day and Kahauale'a) were fed by lava tubes extending from Puʻu ʻŌʻō. Multiple lava flows from the NE spatter cone, collectively called the Kahauale'a flow, traveled across the NE flank of Puʻu ʻŌʻō cone to the cone's base and advanced more than 4.9 km NE over older flows. Peace Day activity consisted of lava flows active above the pali (5 km SE of Puʻu ʻŌʻō), on the pali, and on the coastal plain. Lava also entered the ocean at two main locations spanning the National Park boundary.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

Geological Summary. Kīlauea overlaps the E flank of the massive Mauna Loa shield volcano in the Island of Hawaiʻi. 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 Halemaʻumaʻu 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.