How Beaches and sandbar formed
A beach is formed when waves deposit sand and gravel along the shoreline. Some beaches are made of rocks and pebbles. Over time they are worn smooth from being rolled around by waves. The rocks usually reflect the local geology.
A sandbar is an area of sand, gravel or fine sediment that sits above the water. It may be connected to the shoreline, or it may be offshore. It is formed underwater. As waves break, this pulls material from the shoreline, migrating further into the ocean. During heavy storms, large waves can build sandbars far from shore, until they rise above the water’s surface.
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