Report on Kilauea (United States) — 21 July-27 July 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 21 July-27 July 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, 21 July-27 July 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 21-27 July HVO reported that activity at Kilauea continued from the summit and the east rift zone. At the summit, the level of a lava-pool surface in the deep pit within the floor of Halema'uma'u crater remained mostly stable; glow from the vent was also visible at night. A plume from the vent mainly drifted SW.
At the east rift zone, lava flows that broke out of the TEB lava-tube system advanced E and NE along coastal highway 137 beginning on 17 July and expanded S, filling in the area between the highway and the N-facing scarp of the Hakuma horst. On 24 July, lava flowed N and by the next morning had destroyed a home in Kalapana Gardens. Advancing lava flowed over an area of the horst and on 25 July reached the ocean. On 26 July, lava caused small brush fires and methane explosions in a kipuka on the W edge of the Kalapana subdivision. By 1200 on 27 July, a second lava flow 500 m E of the ocean entry had advanced over the horst and was about 20 m from the ocean. At Pu'u 'O'o crater, intermittent incandescence from lava flows on the N crater floor was visible starting on 24 July.
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.