HVO reported that during 1-7 October lava flowed SE through a tube system from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex. Lava that reached the ocean entry generated a steam plume during much of the reporting period; a plume was absent during 4-6 October. The sulfur dioxide emission rate at Pu'u 'O'o was 1,400 tonnes per day on 5 October, below the background rate as averaged over the past 25+ years.

During the reporting period, Kilauea earthquakes were variously located beneath and to the S of the caldera, along the S-flank faults, and along the SW rift zone. Beneath Halema'uma'u crater small earthquakes per day ranged from less than 40 to 100 (background is about 20-40), but were too small to be located more precisely. The vent in Halema'uma'u crater continued to produce a predominantly white plume with occasional minor ash content that drifted mainly SW, but also in multiple other directions. Weak night-time incandescence was intermittently seen at the base of the plume. The sulfur dioxide emission rate was 900 and 1,100 tonnes per day on 3 and 5 October, respectively. The 2003-2007 rate average was 140 tonnes per day.

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)