Report on Metis Shoal (Tonga) — 30 October-5 November 2019
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 October-5 November 2019
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2019. Report on Metis Shoal (Tonga). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 October-5 November 2019. Smithsonian Institution and US Geological Survey.
19.18°S, 174.87°W; summit elev. 43 m
All times are local (unless otherwise noted)
GeoNet reported that by 1 November the eruption at Metis Shoal (Lateiki) had formed an elongated island, with no visible evidence of the old 1995 dome. According to a news article the new island is about 100 m wide and 400 m long, and had emerged at a location 120 m away from the former island. The article noted that the eruption had ceased.
Geologic Background. Metis Shoal, a submarine volcano midway between the islands of Kao and Late, has produced a series of ephemeral islands since the first confirmed activity in the mid-19th century. An island, perhaps not in eruption, was reported in 1781 and subsequently was eroded away. During periods of inactivity following 20th-century eruptions, waves have been observed to break on rocky reefs or sandy banks with depths of 10 m or less. Dacitic tuff cones formed during the first 20th-century eruptions in 1967 and 1979 were soon eroded beneath the sea surface. An eruption in 1995 produced an island with a diameter of 280 m and a height of 43 m following growth of a lava dome above the surface.