Volcanic eruption

A volcanic eruption is the point in which a volcano is active and releases lava and poisonous gasses in to the air. They range from daily small eruptions to extremely infrequent supervolcano eruptions (where the volcano expels at least 1,000 cubic kilometers of material.) Some eruptions form pyroclastic flows, which are high-temperature clouds of ash and steam that can travel down mountainsides at speeds exceeding that of an airliner.