plume eruption

A type of volcanic activity observed on Io. Plumes arise from rifts or vents on the surface. The eruptive centre is surrounded by a deposit of white or dark red material. The eruption may be violent and short-lived or a longer-lasting eruption of white material, rather like a geyser, consisting of liquid sulphur or sulphur dioxide. Hot liquid from underground changes to a gas as it rushes up through the eruptive centre then condenses again as it falls. Evidence for similar eruptions on Triton can be seen in images returned by Voyager 2.