Macdonald seamount

The Macdonald hotspot is a volcanic hotspot in the southern Pacific Ocean. The hotspot was responsible for the formation of the Macdonald Seamount, and possibly the Austral-Cook Islands chain. It experienced a second eruption in 1989 (ibid).

Macdonald seamount has a shallow summit below sea level, at approximately 20m deep. It is named after Gordon A. MacDonald. It erupted explosively in 1987, during which a specimen of floating lava composed of alkali basalt was sampled by researchers on the R/V Melville and subsequently analyzed. It experienced a second eruption in 1989.

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