Report on Kilauea (United States) — 27 September-3 October 2006
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 27 September-3 October 2006
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2006. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 September-3 October 2006. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
Fountaining on 28 September was reported about 15 m inland of the W edge of the East Lae`apuki bench. Lava jetted about 30 m in the air accompanied by loud rumbling and jetting sounds. Over the next couple of days, 3-4 lava streams were visible on the W side of East Lae`apuki entry, as were incidents of tephra jetting and lava fountaining 15-23 m (50-75 ft) high. Glow had been visible from the East Lae`apuki entry and the Campout flow breakout on the pali, but not from the Ka`ili`ili entry. The consistent lack of visible glow from the Ka`ili`ili entry is due to its inability to build a very large bench, so its continuing activity remains hidden at the base of the seacliff.
Observers reported on 28 September that the floor of Drainhole vent had collapsed, and was replaced by an overturning lava pond. As of 29 September a new tube and flow were forming on the E side of the Campout flow. The USGS field crew also noticed a small stagnant breakout of lava at about 60 m (200 ft) elevation that flowed E to cover a little more of the long-abandoned Royal Gardens subdivision.
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.