Report on Kilauea (United States) — 18 June-24 June 2014
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 18 June-24 June 2014
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2014. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 June-24 June 2014. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 18-23 June HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema‘uma‘u Crater. The lava-lake level dropped several meters on 21 June then returned to an estimated 34-35 m below the floor of Halema‘uma‘u Crater by 22 June. Gas emissions remained elevated. The ambient SO2 concentrations near the vent varied greatly but remained higher than 10 ppm, and frequently exceeded 50 ppm (upper limit of the detector) during times with moderate trade winds. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas; smaller particles may have been dropped several kilometers away.
At Pu‘u ‘O‘o Crater, glow emanated from spatter cones on the N, SE, and S portions of the crater floor, and from a small lava lake in the NE spatter cone. On 17 June geologists mapped five small breakouts as far as 7 km NE from Pu‘u ‘O‘o. The local webcam captured views of the active break-out flows at the N base of Pu‘u ‘O‘o cone as well as distant smoke plumes from the slow-moving lava flow burning vegetation along the NE margin of the Kahauale‘a 2 flow. Overall, however, this slow-moving flow has appeared to be weakening over the past few months.
The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
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.