Report on Kilauea (United States) — June 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 6 (June 1988)
Managing Editor: Lindsay McClelland.
Kilauea (United States) Tube system feeds lava into ocean
Please cite this report as:
Global Volcanism Program, 1988. Report on Kilauea (United States) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 13:6. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198806-332010.
19.421°N, 155.287°W; summit elev. 1222 m
All times are local (unless otherwise noted)
Lava flows . . . continued to enter the ocean along two fronts E of Kupapau Point. The W flow front had two active areas ~200 m apart. At the W end of a 100-m-wide front, minor littoral explosions built a small ephemeral cone that sometimes grew to 1-2 m high by 4 m in diameter, and added pyroclastic material to a growing black sand beach 100 m to the W. Divers observed development of underwater tube systems that extended as much as a few hundred meters from the coast. Flows from the other front sporadically entered the ocean nearly a kilometer to the E. Surface activity upslope along the two lava tube systems was minimal. The lava pond level remained several meters below the rim all month.
Low-level tremor continued . . . near Kupaianaha and Pu`u `O`o. Amplitude varied according to the pattern of lava movement and ranged from frequent tremor variations, minutes apart during gas-piston activity, to relatively steady tremor sustained for hours to days. Some collapse events at Pu`u `O`o were also recorded. The number of microearthquakes was about average in the summit region and East rift zone. Of more than 1,000 earthquakes located . . . in June, 23 registered at M 2.5-5.1. The largest (M 5.1) was centered above the S flank of Kilauea at a depth of 10 km on 7 June.
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: C. Heliker and R. Koyanagi, HVO.