Report on Nishinoshima (Japan) — 26 August-1 September 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 26 August-1 September 2020
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2020. Report on Nishinoshima (Japan). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 26 August-1 September 2020. Smithsonian Institution and US Geological Survey.
27.247°N, 140.874°E; summit elev. 25 m
All times are local (unless otherwise noted)
Japan Coast Guard reported that during an overflight of Nishinoshima on 19 August scientists observed a white plume comprised of volcanic gases rising 3 km from the crater. No lava effusion was visible, though the inner crater was hot. The entire island was covered with ash.
Geologic Background. The small island of Nishinoshima was enlarged when several new islands coalesced during an eruption in 1973-74. Another eruption that began offshore in 2013 completely covered the previous exposed surface and enlarged the island again. Water discoloration has been observed on several occasions since. The island is the summit of a massive submarine volcano that has prominent satellitic peaks to the S, W, and NE. The summit of the southern cone rises to within 214 m of the sea surface 9 km SSE.
Source: Japan Coast Guard