Report on Kilauea (United States) — 30 May-5 June 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
30 May-5 June 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 May-5 June 2012. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 30 May-5 June HVO reported that the circulating and spattering lava lake periodically rose and fell in the deep pit within Kilauea's Halema'uma'u Crater, rising as high as the inner ledge about 60 m below the crater floor. Periodic measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and Pele's hair onto nearby areas. The level of the lava pond in a small pit on the E edge of Pu'u 'O'o crater floor rose back into view. Field geologists observed many lava flows coming down the pali and extending onto the coastal plain. A small new collapse pit in Pu'u 'O'o about 50 m west of the southern spatter cone was observed on 1 June; weak incandescence from this pit was visible in the thermal camera. On 5 June geologists observed a second small collapse pit near the south-central edge that had been covered by a small shield of lava while the lava pond in the E collapse pit had risen to within about 5 m of the rim.
Geological Summary. 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.