Landform sunken or depressed below the surrounding area
A watering hole is a natural depression where water collects and animals come to drink.Karst closed depression with permanent lake Stymfalia, Peloponnese, Greece. Seasonal abundant precipitation drained by 3 sinkholes
In geology, a depression is a landform sunken or depressed below the surrounding area. Depressions form by various mechanisms.
Blowout: a depression created by wind erosion typically in either a partially vegetated sand dune ecosystem or dry soils (such as a post-glacial loess environment).[1]
Oceanic trench: a deep linear depression on the ocean floor. Oceanic trenches are caused by subduction (when one tectonic plate is pushed underneath another) of oceanic crust beneath either the oceanic crust or continental crust.
A basin formed by an ice sheet: an area depressed by the weight of the ice sheet resulting in post-glacial rebound after the ice melts (the area adjacent to the ice sheet may be pulled down to create a peripheral depression.)[4]
