Report on Kilauea (United States) — 8 October-14 October 2008
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 8 October-14 October 2008
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2008. Report on Kilauea (United States) (Sennert, S, ed.). Weekly Volcanic Activity Report, 8 October-14 October 2008. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
HVO reported that during 8-14 October lava flowed SE through a tube system from underneath Kilauea's Thanksgiving Eve Breakout (TEB) and rootless shield complex, reaching the Waikupanaha ocean entry. Multiple lava breakouts, including a small 'a'a flow E of the Royal Gardens subdivision, and points of incandescence on the pali were noted. The sulfur dioxide emission rate at Pu'u 'O'o was 1,400 tonnes per day on 12 October, below the background rate since early 2005. Explosions at the ocean entry were reported on 13 October.
During the reporting period, Kilauea earthquakes were variously located beneath and to the S of the caldera, and along the S-flank faults. Beneath Halema'uma'u crater earthquakes ranged from 40 per day to more than 80 (background is about 40), but were too small to be located more precisely. The vent in Halema'uma'u crater continued to produce a predominantly white plume, which was occasionally tinged brown in association with small local earthquakes, that drifted mainly SW and S. Night-time incandescence was intermittently seen at the base of the plume. An explosion on 12 October produced pulsating ash-rich clouds with pulses of incandescent gas and tephra. Significant tephra deposits included frothy ejecta up to fist and grapefruit sizes. In a video of the eruption, incandescence in the plume appears to be well above the level of the crater rim (about 70 m above the vent). The sulfur dioxide emission rate was 1,200 tonnes per day on 10 October. The 2003-2007 rate average was 140 tonnes per day.
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.