The Hawaiian Volcano Observatory (HVO) reported that the eruption within Kilauea’s Kaluapele summit caldera, characterized by episodic fountaining, incandescence, and intermittent spatter at vents along the SW margin of Halema’uma’u Crater, continued at variable levels during 19-26 August. Incandescence at the N vent and the cracks above it was visible during 19-21 August. Spattering at the N vent was visible overnight during 20-21 August. Spatter bursts, Strombolian jetting, and low dome fountains were intermittently visible in webcam images starting at 1615 on 21 August and continuing at least through the morning of 22 August. Lava overflows from the vent occurred during that time, specifically at 2046 on 21 August and at 0103 and 0124 on 22 August. Spattering at the N vent became continuous at around 0830 on 22 August and then intensified; by 1145 lava overflows became sustained. The spattering had built up a cone inside the N vent, sealing off part of the vent. Fountaining that began at 1404 was arcuate and about 30 m high, and within 15 minutes was feeding multiple lava flows on the caldera floor. Sometime around 1600-1700 low spatter fountains at the S vent produced small lava flows. At 1923 a new vent opened in the intermediate area of glowing cracks between the N and S vents. Fountains at both the S vent and the new vent generally rose less than 10 m, though fountains at the new vent intensified later in the evening and rose as high as 30 m. The S vent ceased erupting at around 0040 on 23 August, the intermediate vent ceased about two hours later at 0246, and the N vent ceased at 0252. Approximately 8,400,000 cubic meters of lava had erupted during the 12.6 hours of fountaining, at an average of 185 cubic meters per second. Lava flows covered more than 75 percent of the caldera floor. Minor incandescence at the cone and across the lava flow field was seen during 23-24 August and at the N vent during 23-25 August. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

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)