Motion of Kilauea volcano during sustained eruption from the Puu Oo and Kupaianaha vents, 1983-1991

Abstract

Kilauea erupted almost continuously from January 1983 through 1991. Although the summit began subsiding during the rift zone dike intrusion that initiated this eruption, remarkably steady ground surface motions began in late 1983 and continued until late 1990. During these 7 years the summit and upper rift zones subsided up to 10-11 and 4-8 cm yr-1, respectively, and summit baselines contracted up to 6 cm yr-1. Dislocation models show that much of Kilauea's edifice migrated seaward, producing ground surface motions along the south flank of up to about 6 cm yr-1. The magnitude 6.1 earthquake of 1989 punctuated these motions along the eastern south flank, producing more than 25 cm of seaward displacement and, 15 km east of the epicenter, up to 24 cm of subsidence south of the lower east rift zone. -from Authors