Sand Bar

• Sand bars are formed due to longshore drift.
• Swash is where waves, driven by prevailing wind push materials up the beach at an angle
• The returning backwash is dragged back by gravity down the beach at right angles
• Bars form when there is a change in direction on a coastline which allows a sheltered area for deposition
• Sand bars are formed when a spit grows across the entrance to a bay, connecting two headlands enclosing a sheltered lagoon behind it
• This happens when there is no strong flow of water from a river into the sea and through time the stagnant lagoon water is infilled by deposition