"The . . . eruption continued this month with lava entering the ocean along a 500-m-long front between the Kamoamoa and Lae Apuki areas in Hawaii Volcanoes National Park. Explosive activity was reported on 8 May, and continued with increased vigor through the end of the month. Some littoral explosions threw incandescent lava as high as 50 m in the air, and detonations could be heard from the highway (>500 m away). Large cracks were observed running parallel to the pre-April shoreline. Surface flows were rare during May. The Pu`u `O`o lava pond was active and its surface was 79-88 m below the crater rim.

"On 3 June a large channelized aa flow broke out of the lava tube at the 125-m elevation and advanced down to the coastal plain. Within a day, all break-outs from this flow were pahoehoe. The flow spread out on the coastal flats and was within 500 m of the shoreline by 6 June. More skylights opened at 150 m elevation."

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.

Information Contacts: T. Mattox, HVO.