Here are the types of sediment that are deposited first as a river slows down:
1. Boulders and Cobbles: These are the largest and heaviest sediment particles. They are deposited first because they require a higher velocity of water to remain suspended. As the river slows down, these particles settle to the bottom first.
2. Gravel: Gravel particles are smaller than boulders and cobbles but are still relatively large and heavy. They are deposited next after boulders and cobbles.
3. Sand: Sand particles are smaller than gravel but are still visible to the naked eye. They are deposited after gravel as the river's velocity decreases further.
4. Silt: Silt particles are smaller than sand and are barely visible to the naked eye. They are deposited after sand as the river slows down even more.
5. Clay: Clay particles are the smallest and lightest sediment particles. They remain suspended in the water for a long time and are deposited last as the river's velocity approaches zero.
The deposition of sediment in a river follows a pattern known as graded bedding, where the larger and heavier particles are deposited at the bottom, followed by progressively smaller particles towards the top. This pattern reflects the gradual decrease in water velocity as the river slows down.
