If  deposition of sediment at the mouth of a river by water fanning out is called by a Greek letter, then the deposition of sediment at the mouth of a river by water fanning out is called by what name?

Answer choices:
- unidirectional
 - Sediment
 - Calcium carbonate
 - patch reefs
 - A Greek letter
 - barrel-shaped
 - swamp vegetation
 - flooding

 

     A Greek letter     