アムステルダム島

The elliptical 7 x 10 km Amsterdam Island is the northernmost subaerial volcano on the Antarctic Plate. The basaltic volcano is located near the axis of the East Indian Ocean Ridge adjacent to the Indian Plate. Amsterdam volcano was formed during two episodes of cone growth accompanied by the formation of small calderas. The caldera of the youngest eruptive center, 2 km ENE of the earlier one, contained a lava lake that fed several stages of lava outflows. Minor late-stage eruptions formed more than two dozen scoria cones and many small lava flows. No observed eruptions are known, although the fresh morphology at Dumas Crater on the NE flank suggests it may have occurred as recently as a century ago (Nougier, 1982).