Lava production continued into early December. . .. Lava flowed into the sea 1-25 November, the W lobe continuously (in the national park, W of Kupapau Point), and the eastern intermittently (E of Kupapau Point), as in October. Activity at the coast declined to a trickle on 26 November. The next day lava broke out at several points between 240 and 170 m elevation, indicating blockage within the tube system. Several flows advanced over the prominent south flank fault scarp, reaching 60 m elevation. By 2 December, the middle lobe had reached the previously covered coast highway and by 7 December lava was again flowing into the ocean near Kupapau Point, on top of previous flows. In Royal Gardens subdivision, lava movement was intermittent through November, primarily slow ooze-outs on top of older flows. However, lava re-entered Royal Gardens in early December, and one lobe destroyed the last remaining house in the SE part of the subdivision before stagnating on 4 December.

Shallow tremor continued at a low level . . . near the active vent and Pu`u `O`o. Accompanying microshocks caused by rockfalls, degassing, or thermal compensation in recent lava flows occurred several to 100 times a day. Intermediate and deep tremor activity in summit region was intermittent. Minor bursts of short-period events beneath the summit were recorded for a week in mid-November, and were followed a week later by a 2-day swarm of long-period events. Many of the month's earthquakes occurred at intermediate depths . . . under the summit and S flanks of Kīlauea.

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.