Superplumes of the type on which Yellowstone sits are rather like martini glasses-thin on the way up, but spreading out as they near the surface to create vast bowls of unstable magma.

黄石公园所在的几处超级热柱，很像马提尼酒杯，越往上越细，但到了接近地面的地方就向外张开，变成盛着不稳定岩浆的许多“大碗”。