During 8-14 December, HVO reported that activity at Kilauea continued from the summit caldera and the east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within Halema'uma'u crater remained mostly stable at approximately 130 m below the crater floor, periodically rising 15-20 m higher. Nighttime incandescence has been visible from the Jaggar Museum on the NW caldera rim since early 2010. A plume from the vent drifted in multiple directions and deposited ash and fresh spatter nearby.

At the east rift zone, lava flowed a short distance through the TEB lava-tube system before breaking out onto the surface at a saddle between two rootless shields at around the 610 m elevation, forming a lava pond atop a new shield. Two breakout lava flows traveled about 120 m down the pali. Lava flows from a small spatter cone on the Pu'u 'O'o crater floor continued. A small lava flow traveled W on 10 December. On 13 December lava flowed from a second spatter cone, located on the NW edge of the crater.

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)