HVO reported that lava effusion from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater continued at variable rates during 5-12 April. Lava from a vent flowed into the active W part of the lava lake, which comprised about 2.3 percent of the total crater floor’s surface, and onto the crater floor. The surface of the lava lake was active all week, and the height of the lake fluctuated. Numerous ooze outs of lava were visible along the lake’s NW, NE, E, and SE margins; a more substantial ooze-out at the N margin was active during 6-7 April. A small outbreak at the W vent was visible overnight during 8-9 April. Just after 2300 on 10 April a flow emerged from the S side on the vent that covered areas along the southwest and western margins through 12 April. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.

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)