Volcanic dome

A volcanic dome is a volcanic feature formed by the extrusion of extremely viscous lava. Instead of flowing away from the volcanic crater, viscous lava grows into a large dome. Domes may reach heights of several hundred metres, and can grow slowly and steadily for months or years.

Volcanic domes can be very fragile structures, and often partially collapse. These dome collapses can trigger pyroclastic flows. Ultimately, many volcanic domes are destroyed by large explosive eruptions.

Well known examples of volcanic domes include several formed at Mount St. Helens after the large eruption of 1980, and the dome at Soufriere Hills volcano in Montserrat, which has grown and collapsed repeatedly since volcanic activity began there in 1995.