On 5 November at 1130, ~1/3 of the 400-450 x 60 m lava bench collapsed, and numerous smaller bench collapses were detected seismically throughout November. A large littoral cone that formed on 28 November produced 1-5-cm flakes of volcanic glass.

On 10 November, a series of surface outbreaks near the top of the fault scarp at ~350 m elevation fed lava that flowed into the Royal Gardens subdivision but caused no threat to remaining structures. By 14 November, the flow was barely moving. Two weeks later, an outbreak occurred at 180 m elevation, flowed E of the subdivision, and stagnated days later at ~100 m elevation. The Kupaianaha lava pond level remained stable at 25-30 m below the rim through November. During overflights on the 3rd and the 28th, low fountaining (~5-10 m high) was observed in Pu`u `O`o crater, covering as much as ½ of its floor with lava. Irregular tremor . . . near Pu`u `O`o had ended 4 November and typical low-level tremor resumed. Most upper East rift zone events were deeper than 5 km except along the rift axis where events were generally more shallow. Seismicity was steady beneath Kiluaea's S flank, but episodic swarms of intermediate-depth (5-13 km), long-period earthquakes were measured beneath the summit.

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.

Information Contacts: C. Heliker and R. Koyanagi, HVO.