Vocabulary 7-12 Aerial view- a view from above; a bird’s eye view Velocity- the speed at which the stream flows Stream system- includes all the parts of a stream (mouth, head, channel, etc.) Delta- The triangular shaped sediment deposited at the mouth of the river. Flood Plain- A flat area next to the stream that is made up of loose sediment (which gets deposited when the stream overflows) Canyon- A deep, steep, walled gorge carved in a rock by a stream or glacier. Valley- A long, low area carved by a stream or glacier with higher areas on both sides. Mouth- The point at which water from a river or stream empties into another body of water, such a lake or an ocean. Stream channel- the course along which water moves.