are holes or depressions
in the river bed.
vary in size from a few centimetres to several
metres in diameter.
are formed by corrasion
in rivers where the fast-flowing
water swirls, especially if the river
bed is uneven.
of stones and pebbles carried by the river whirl
around, drilling circular
depressions into the river bed.
flowing water keeps the fragments in motion, constantly wearing
away the sides
of the depressions.
gradually become deeper and wider
to become potholes.
two potholes join
to create an even larger pothole.
Formation of a pothole.
Potholes in the World