Report on Additional Reports (Unknown) — May 1992
Bulletin of the Global Volcanism Network, vol. 17, no. 5 (May 1992)
Managing Editor: Lindsay McClelland.
Additional Reports (Unknown) Fiji: Pumice rafts; source unknown
Please cite this report as:
Global Volcanism Program, 1992. Report on Additional Reports (Unknown) (McClelland, L., ed.). Bulletin of the Global Volcanism Network, 17:5. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199205-600500
Lat Unknown, Unknown; summit elev. m
All times are local (unless otherwise noted)
A Fiji Air passenger saw two narrow, elongate rafts of drifting pumice in the Kadavu passage ~30 km SE of Suva (figure 1) on 24 January. Fiji's Maritime Surveillance Centre issued a warning to mariners, published in newspapers on 27 January. Pumice was subsequently reported from ships roughly 50 km SW and 160 km NW of the initial observation.
|Figure 1. Map of Fiji, from Baleivanualala, 1992, showing locations of pumice rafts seen in early 1992.|
A search of the Suva Harbour area on 27 January revealed pumice floating in the Suva Passage and stranded at the high-tide line around the Suva Peninsula. The pumice was gravel-sized, with the largest fragment ~4 cm across. The samples were weathered and some included living barnacles up to 9 mm long. After the 1984 Home Reef (Tonga) eruption, barnacles 1.5 cm long were found on pumice that was at most 25 weeks old, so a provisional maximum age of 15 weeks was assigned by Baleivanualala to the barnacles found in January 1992. Given an estimated drift rate of ~12 km/day (Rodda and Jones, 1990), the pumice might have traveled 1,300 km from the eruption site. No reports of eruptions in the Tonga-Kermadec region have been received.
References. Baleivanualala, V., 1992, Drift pumice in Kadavu Passage, January 1992: Fiji Mineral Resources Department Note BP57/1, 3 pp.
Rodda, P., and Jones, T.D., 1990, The 1990 reports of drift pumice in Fiji (Corrigendum): Fiji Mineral Resources Department Note BP1/91.
Geological Summary. Reports of floating pumice from an unknown source, hydroacoustic signals, or possible eruption plumes seen in satellite imagery.
Information Contacts: V. Baleivanualala and P. Rodda, Mineral Resources Dept, Suva, Fiji.