Report on Kilauea (United States) — 25 January-31 January 2012
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 25 January-31 January 2012
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2012. Report on Kilauea (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 25 January-31 January 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 25-31 January, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. During 25-27 January lava ejections on the SE edge built a small spatter rampart and produced small lava flows on the inner ledge.
Incandescence was visible on the NE, SE, and W edges of the Pu'u 'O'o crater floor during 25-31 January. On 25 January lava started to fill a Pu'u 'O'o crater floor depression and continued episodically all week. Geologists on a 26 January overflight reported lava flows 4 km SE of Pu'u 'O'o. On 27 January the SE and NE vents started to effuse lava. During 24-31 January, thermal anomalies were seen in satellite imagery 3-4 km SE of Pu'u 'O'o cone.
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.