HVO reported that lava effusion from vents in the lower W wall of Kīlauea's Halemaʻumaʻu Crater continued at variable rates during 15-22 March; effusion briefly paused during 0145-0445 on 18 March. Lava flowed in the active W part of the lava lake causing circulation in the lake that was visible on most days. At around 0700 on 16 March a lava flow originating from the embayment just N of the western vent area traveled NW onto the crater floor; this flow periodically advanced through the week. Ooze outs of lava along the lake’s margins were visible on a few of the days; a notable one began along the N margin at 0345 on 21 March and persisted through the next day. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.

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.