Report on Kilauea (United States) — 21 January-27 January 2004
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
21 January-27 January 2004
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2004. Report on Kilauea (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 21 January-27 January 2004. Smithsonian Institution and US Geological Survey.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
On 22 January lava was emitted from the vent that formed at Kilauea on 19 January (the vent and lava flow S of Pu`u `O`o cone were named MLK in honor of the activity that began on Martin Luther King Jr.'s birthday). There were also surface lava flows at the W side of the Amalgamated Bend shield SW of Pu`u `O`o. By 26 January there were no surface lava flows at the MLK vent, and incandescence was only visible at the S part of the rootless shield complex. On 23 January moderate-to-strong tremor beneath Kilauea's caldera stopped, while it lessened at Pu`u `O`o. On 26 January deflation that began on 18 January ended at Pu`u `O`o after reaching 24.7 microradians. This was probably the largest deflation event since early 1997.
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.