Report on Kilauea (United States) — 4 June-10 June 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 4 June-10 June 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Kilauea (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 4 June-10 June 2003. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
Small amounts of lava continued to flow into the sea at the Highcastle entry during 4-10 June, and lava flows were sometimes visible on Pulama pali and the coastal flat. Seismicity at the summit of Kilauea continued at moderate-to-high levels, with many small, low-frequency earthquakes occurring at shallow depths beneath the summit caldera for more than a week. The tiny earthquakes occurred at the notably high rate of 2-4 per minute. Little or no volcanic tremor accompanied the swarm, however. Volcanic tremor at Pu`u `O`o remained moderate to high, as is the norm. Almost cyclic inflation and deflation occurred during the report week, but did not culminate in significant overall tilt.
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.