Fissure
Photograph by C. Neal, June 25, 1983, U.S. Geological Survey.
A fissure is a "surface of fracture or a crack in rock along which there is a distinct separation" (Bates and Jackson, 1980). A fissure eruption is an "eruption that takes place from an elongate fissure rather from a central vent" (Bates and Jackson, 1980). The fissure in this photograph was a vent for an early episode of the Puu Oo eruption. Lava trees are prominent on the horizon. Spatter covers the ground adjacent to the fissure. Lava within the fissure is red, due to oxidation.
