Report on Kilauea (United States) — 17 June-23 June 2009
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 17 June-23 June 2009
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2009. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 17 June-23 June 2009. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
Daily reports from HVO about Kilauea during 17-23 June indicated continuing visible glow from the Halema'uma'u vent. Molten lava remained in the neck of a funnel-shaped cavity in the floor of Halema'uma'u Crater. Webcam views showed the lava level rising several meters for brief periods before returning to depths of about 290 m below the crater rim and 205 m below the crater floor, as determined by laser-ranging measurements. Throughout the week lava from east rift zone vents flowed through tubes to the coast and entered the ocean at two locations west of Kalapana; active surface flows also continued on the pali within the abandoned Royal Gardens subdivision. Sulfur dioxide emission rates from the Halema`uma`u and Pu`u `O`o vents remained elevated. The plume continued to carry glassy bits of spatter and small amounts of ash. A deflation-inflation event began on 22 June and was continuing the next day.
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.