A very violent type of volcanic activity characterized by the release of nuées ardentes (glowing clouds of gas-fluidized material). Highly viscous lavas are typically involved and the eruptions may be preceded by the growth of a lava dome. Nuées ardentes may be formed by the explosive disruption of a growing dome, or by mechanical collapse of a dome growing on a steep slope. See volcano. Compare hawaiian eruption; plinian eruption; strombolian eruption; vesuvian eruption; vulcanian eruption.