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Report on Kilauea (United States) — 17 August-23 August 2011


Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 17 August-23 August 2011
Managing Editor: Sally Sennert.

Please cite this report as:

Global Volcanism Program, 2011. Report on Kilauea (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 17 August-23 August 2011. Smithsonian Institution and US Geological Survey.

Weekly Report (17 August-23 August 2011)


United States

19.421°N, 155.287°W; summit elev. 1222 m

All times are local (unless otherwise noted)

During 17-23 August, HVO reported that lava continued to trickle onto the collapsed floor of Kilauea's Pu'u 'O'o' crater and some spattering occurred from various areas on the floor. The only activity on the W flank was observed during 17-20 August; a small lava flow from the base of the N pond rim near the Kamoamoa fissures and a larger flow from the N flow branch were both active. During 20-21 August a small amount of lava emitted from a vent on the S crater floor flowed a short distance. Later, lava started issued in larger quantities from another source on the S part of the floor that quickly filled in a low trench. Lava continued to flow onto the crater floor during the next two days.

During 17-18 August lava flowed onto the floor of the vent inset within the E wall of Halema'uma'u Crater. By the next day a persistent spattering source at the W edge of the cavity pushed the lava surface sluggishly from W to E. During 19-21 August drain-and-fill cycles were observed; the highest level of the lava surface was below the inner ledge 75 m below Halema'uma'u Crater floor.

Geological Summary. Kilauea overlaps the E flank of the massive Mauna Loa shield volcano in the island of Hawaii. Eruptions are prominent in Polynesian legends; written documentation since 1820 records frequent summit and flank lava flow eruptions interspersed with periods of long-term lava lake activity at Halemaumau crater in the summit caldera until 1924. The 3 x 5 km caldera was formed in several stages about 1,500 years ago and during the 18th century; eruptions have also originated from the lengthy East and Southwest rift zones, which extend to the ocean in both directions. About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1,100 years old; 70% of the surface is younger than 600 years. The long-term eruption from the East rift zone between 1983 and 2018 produced lava flows covering more than 100 km2, destroyed hundreds of houses, and added new coastline.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)