In this diagram, we see a wide range of salinities (0.1 to 32), wave processes that dominate at the mouth of the estuary, tidal processes that occur in the middle region, and river or fluvial ...

but an estuary has a gradation of salt water dilution from fully salt water at its mouth to fresh water at its head, and experiences tidal f luctuations. For the sake of completion, a river is a ...