Lava continued to enter the ocean at the West Highcastle entry at Kilauea during 1-8 April. Surface lava flows were visible on the Kohala lava flow and Pulama pali. During the beginning of the report period, lava traveled over the Chain of Craters Road. The lava cooled and ceased flowing over the road by the 3rd. Generally, seismicity remained at normal to below-normal levels. The summit swarm of long-period earthquakes and tremor, which began last June, was weak, with scattered earthquakes and sparse low-frequency tremor. Volcanic tremor at Pu`u `O`o was relatively high during the last few days of the report period. Small deformation changes occurred mostly at Pu`u `O`o.

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)