Report on Kilauea (United States) — 3 February-9 February 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 3 February-9 February 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 3 February-9 February 2010. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 3-9 February, HVO reported an active lava surface about 200 m below a vent in the floor of Kilauea's Halema'uma'u crater. The lava surface occasionally spattered, and both rose and drained through holes in the cavity floor. A plume from the vent drifted mainly SW, dropping small amounts of ash, and occasionally fresh spatter, downwind. Measurements indicated that the sulfur dioxide emission rate at the summit remained elevated; 1,200 and 700 tonnes per day were measured on 4 and 8 February, respectively. The 2003-2007 average rate was 140 tonnes per day.
Lava from beneath the Thanksgiving Eve Breakout (TEB) and rootless shield complex flowed over 3 km SE through a lava tube system before breaking out onto the surface. Thermal anomalies detected by satellite and visual observations revealed active lava flows above and on the pali, and on the coastal plain. By 8 February, pahoehoe lava flows had advanced 700 m from the base of the pali S onto the coastal plain. Incandescence was sometimes seen from a vent low on the S wall of Pu'u 'O'o crater.
Geologic Background. Kilauea, which overlaps the E flank of the massive Mauna Loa shield volcano, has been Hawaii's most active volcano during historical time. Eruptions are prominent in Polynesian legends; written documentation extending back to only 1820 records frequent summit and flank lava flow eruptions that were interspersed with periods of long-term lava lake activity that lasted until 1924 at Halemaumau crater, within the summit caldera. The 3 x 5 km caldera was formed in several stages about 1500 years ago and during the 18th century; eruptions have also originated from the lengthy East and SW rift zones, which extend to the sea on both sides of the volcano. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 km2, destroying nearly 200 houses and adding new coastline to the island.