Report on Kilauea (United States) — 6 May-12 May 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 6 May-12 May 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 6 May-12 May 2015. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 6-12 May HVO reported that the circulating lava lake occasionally rose and fell in the pit within Kilauea's Halema'uma'u Crater. Lava overflowed the rim multiple times almost daily, and since the first overflow on 28 April, had built up a rim that by 8 May was 10 m higher than the Halema'uma'u crater floor. Contemporaneously with deflation detected during 10-12 May, the lake receded, and by 12 May was barely visible from the Jaggar Museum.
At Pu'u 'O'o Crater, lava erupted from several vents multiple times onto the crater floor. An overflight on 8 May revealed an active lava pond in an isolated vent W of the main crater. The June 27th NE-trending lava flow continued to be active with three areas of breakouts within and along the flow-field margins, within 8 km NE of Pu'u 'O'o. Most of the surface flows were fed from the 21 February breakout and located less than 3 km from the NE rim of Pu'u 'O'o. Forest burned about 8 km NE of the 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.