Report on Kilauea (United States) — 5 December-11 December 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
5 December-11 December 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 5 December-11 December 2012. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 5-11 December HVO reported that on most days the circulating lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Occasional measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas.
At Pu'u 'O'o Crater, lava circulated within the perched lava lake at the NE part of the crater, and glow emanated both from spatter cones on the SE part of the crater floor and from a spatter cone at the NW edge. The lava lake briefly overflowed on 5 December, and small, short-lived lava flows emanated from the spatter cones during 7-9 December. Through the week a spatter cone formed over the lava lake, covering the surface.
Lava flows remained active in two branches on the coastal plain: a small W branch, and a larger E branch with scattered activity extending from the pali to the coast E of the easternmost boundary of Hawai'i Volcanoes National Park. An ocean entry was marked by a weak and variable plume near Kupapa'u, with lava entering the water in at least two different areas.
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.