Report on Kilauea (United States) — November 1976
Natural Science Event Bulletin, vol. 1, no. 14 (November 1976)
Managing Editor: David Squires.
Kilauea (United States) Summit deflation
Please cite this report as:
Global Volcanism Program, 1976. Report on Kilauea (United States) (Squires, D., ed.). Natural Science Event Bulletin, 1:14. Smithsonian Institution. https://doi.org/10.5479/si.GVP.NSEB197611-332010.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
A [gradual] 40 µrad deflation of the summit occurred [aseismically] during late August and September. In late October, a 15 cm dilation and a several-acre area of steam-killed trees were noted N of Kalapana on the E rift zone, about 25 km from the summit of Kilauea. It is assumed that the magma that left the summit area migrated into the E rift zone, causing the effects observed near Kalapana.
[Intrusive episodes on 21 June and 14 July 1976, not reported in the original Bulletin, are described in the comprehensive summary of Dzurisin and others, 1984.]
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.
Information Contacts: G. Eaton, HVO; D. Shackelford, CA.