1. Sediments Become Rocks
Activity 4

2. Sedimentary Rocks Sediments
rocks formed when layers of sediment were deposited one on top of another and became squeezed and cemented together (weathering, erosion, and pressure)
Sediments
Small particles of soil and weathered rock

3. 1. Weathering
The process by which rocks in Earth’s crust are broken down into smaller pieces (sediments)
Mechanical Weathering
The physical breakdown of rocks into smaller pieces
The small pieces have the same chemical make up as the larger pieces
Causes:
wind – water – pressure - temperature – plants

4. Soil
The loose weathered material on the surface of Earth’s crust in which plants can grow
All soil formation begins with the weathering of rock
Soils differ depending on the rock sediment in soil

5. Chemical Weathering
The breakdown of rocks caused by a chemical reaction with another substance.
It results in a change in the chemical composition of rocks
Causes:
Rainwater, acids, and oxygen in the air act on rocks

6. 2. Erosion
When sediments are carried by wind and water from one location to another
This is a destructive process
3. Deposition
When sediments carried by wind or water are deposited on the ground somewhere else (the material is “laid down”)
This is a constructive process

7. 4. Cementation
The grains of sediment are compacted and cemented together to form sedimentary rock

8. Fossils *put foldable in and add notes**
1. Formed in sedimentary rock from the remains of prehistoric animals and plants
2. As sediments are deposited, the remains of plants and animals may come to rest on top of them
3. They are covered by more layers of sediment
4. If the rock forms soon after this, the imprint of the skeleton or leaf may be left behind in the rock

9. How Fossils form in Sedimentary Rocks