On volcanoes, a fissure is an elongated fracture or crack at the surface from which lava erupts. Fissure eruptions typically dwindle to a central vent after a period of hours or days. Occasionally ...

Vents may consist of a single, circular-shaped structure, a large elongated fissure or fracture (as seen on the diagram above) or a tiny ground crack. Nyiragongo is notorious for releasing large ...

Tension along a fault zone created the fracture, opening up a fissure in a field of lava that originally flowed from nearby Green Mountain, a small shield volcano, some 740,000 years ago.