When landslides enter stream channels during floods, they become debris flows--large volumes of water containing soil, rock, and, frequently, large organic debris.
(landslides; enter; stream channels; T:during floods) (they; become; debris flows; T:When landslides enter stream channels during floods) (large volumes of water; containing; soil, rock, and, frequently, large organic debris)
landslides they large volumes of water
enter become containing
stream channels T:during floods
debris flows T:When landslides enter stream channels during floods
soil, rock, and, frequently, large organic debris