Limestone begins to soften because of acid rain.

True or false: Weathering is the process of breaking down rocks.

A delta is formed at the mouth of a large river.

True or false: Deposition happens when sediment is dropped in a new location.

A glacier transports rock and debris that build up to form a moraine.

The repeated motion of waves pick up loose sand from the beach.

Wind carries sand and forms a sand dune.

Powerful waves crash into a rock with cracks. A layer of air gets trapped at the bottom of the crack. When the wave retreats, the air that was trapped is released with a powerful force and weakens the rock.

Ice melts in the crack of a large boulder and carries away loose sediment.

Sediment is picked up from the banks of a flowing river.

Dust and sand are blowing in the air during a wind storm.

Rock and debris from the side of a mountain are picked up by a moving glacier.

Water seeps into the cracks of a mountainside and freezes with cold temperatures. New and larger cracks develop.