 Geologists have debated about what caused the slide debris to travel the distance it did . The " air cushion " theory , an early hypothesis , postulated that a layer of air was trapped between the mass of rock and the mountain , which caused the rock to move a greater distance than would otherwise be expected . " Acoustic <unk> " is another theory , which suggests that large masses of material create seismic energy that reduces friction and causes the debris to flow down the mountain as though it is a fluid . Geologists created the term " debris avalanche " to describe the Frank Slide . 
