An___fan is a fan shaped discharge of sediment and debris, usually caused by a sudden and intense downpour of rain, which flows quickly over changes (breaks, gulch, etc.) in topography.
This is an alluvial fan. An alluvial fan can be described bas sediments accumulation. It is shapes like a fan or a triangle. It is a deposit of sand, gravel wooden deposits, debris and silt. We call these alluvium. The creation of alluvial fans is as a result of the interaction of flowing water with hills and mountains. They are depositional land forms and flowing water causes them.
