Smellie and other scientists newly discovered a similar monogenetic subglacial tuff cone within the ice of Antarctica and could determine the thickness of ice which covered the vent during eruption. The Antarctic cone did lie under a polar ice sheet and not a temperate glacier as was the case with Keilir. Aditionally, the Antarctic cone is much older (around 640 000 years), whereas Keilir is up to 100 000 years old. And the tuff cone from Victoria Land, Antarctica, is placed next to known granitic plutonic complexes and seems to be a parasitic cone of a stratovolcano, whereas Keilir is located adjacent to presently active volcanic systems and looks as if it were placed on top of the shield volcano Þráinskjöldur, though the last one is younger than the subglacial formation. Interestingly, similar tectonics, rift zones, are behind both expressions of volcanism: the West Antarctic Rift System on the one hand, and in the case of Keilir the Reykjanes Rift as part of the rift zones crossing Iceland. Also similar are their rocks - mafic lapilli tuff (in Icelandic: móberg).