Fjord

Definition of Fjord: A narrow, deep estuary excavated by glaciers and that commonly has a sill at its mouth. This is the common definition for Fjord, other definitions can be discussed in the article

Geirangerfjord in Norway

Notes

The water body is highly stratified with fresh/brackish water on top of a seawater bottom layer. The strong density gradient inhibits mixing with surface water. Due to slow water renewal in the bottom layer together with organic matter mineralization, the bottom layer is generally deprived of oxygen.