Report on Kilauea (United States) — 3 August-9 August 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 3 August-9 August 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Kilauea (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 3 August-9 August 2016. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
During 3-9 August HVO reported that the lava lake continued to rise and fall, circulate, and spatter in Kilauea’s Overlook vent. Late on 6 August an explosions triggered by a rockfall into the lake ejected voluminous amounts of hot spatter and rock debris onto the SE rim of Halema’uma’u Crater, covering a broad swath 80 m long and 50 m wide around the formerly-closed public overlook area.
Several incandescent vents on Pu’u ‘O’o Crater’s floor were evident in webcam images. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna in an area that spans 150-240 m wide. A small delta had formed at the entry. An active lobe of lava advanced along the W side of the flow field, crossed the Emergency Access road 500 m W of the main flow, and entered the ocean overnight during 8-9 August.
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.