Report on Kavachi (Solomon Islands) — January 1997
Bulletin of the Global Volcanism Network, vol. 22, no. 1 (January 1997)
Managing Editor: Richard Wunderman.
Kavachi (Solomon Islands) Submarine ejection of mud and hot ash; plumes rise to 2.1 km
Please cite this report as:
Global Volcanism Program, 1997. Report on Kavachi (Solomon Islands). In: Wunderman, R (ed.), Bulletin of the Global Volcanism Network, 22:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199701-255060.
8.991°S, 157.979°E; summit elev. -20 m
All times are local (unless otherwise noted)
On 16 January a Solair pilot reported continuous ejection of mud and hot ash up to 2,100 m altitude. When the pilot returned on 17 January, the eruption was continuing with intermittent plumes reaching similar heights. On 29 January the sea water near the volcano was discolored and dirty, however, there were no reports of eruptive activity.
Kavachi is a basaltic to andesitic shallow submarine volcano. It has produced ephemeral islands at least nine times since its first recorded eruption in 1939. The last record of eruptive activity was in May 1991 (see BGVN 16:07).
Geologic Background. Named for a sea-god of the Gatokae and Vangunu peoples, Kavachi is one of the most active submarine volcanoes in the SW Pacific, located in the Solomon Islands south of Vangunu Island about 30 km N of the site of subduction of the Indo-Australian plate beneath the Pacific plate. Sometimes referred to as Rejo te Kvachi ("Kavachi's Oven"), this shallow submarine basaltic-to-andesitic volcano has produced ephemeral islands up to 1 km long many times since its first recorded eruption during 1939. Residents of the nearby islands of Vanguna and Nggatokae (Gatokae) reported "fire on the water" prior to 1939, a possible reference to earlier eruptions. The roughly conical edifice rises from water depths of 1.1-1.2 km on the north and greater depths to the SE. Frequent shallow submarine and occasional subaerial eruptions produce phreatomagmatic explosions that eject steam, ash, and incandescent bombs. On a number of occasions lava flows were observed on the ephemeral islands.
Information Contacts: Alison K. Papabatu, Ministry of Energy, Water and Mineral Resources, Solomon Islands.