1. Sedimentary Rocks

2. Sedimentary Rocks are #1
Earth’s crust was made of IGNEOUS rocks
But 75% of the rocks on the Earth’s crust are SEDIMENTARY!
Why?

3. Sedimentary rocks are created from the EROSION and DEPOSITION of other rocks.

6. Formation of Sedimentary Rocks
5 steps
1. Weathering – any process that breaks rocks into smaller pieces (sediment)
2. Erosion – the process of removing the sediments (wind, water, etc.)
3. Deposition – the dropping of sediments
4. Compaction – squeezing layers of sediments together
5. Cementation – when dissolved minerals seep into the tiny spaces between the sediments, cementing them into a solid rock

7. Strata = Layering of Rock
Youngest Layers
Oldest Layers

8. Sedimentary Rocks are the ONLY rocks that contain FOSSILS!!

9. There are 3 main types of Sedimentary Rocks

10. 1. Clastic Sedimentary Rocks
Rocks that break down under forces of nature - WIND and WATER!!
Made of pieces of other rocks

11. Examples of Clastic Sedimentary Rock
Conglomerate

12. Examples of Clastic Sedimentary Rock
Shale
Made up of clay sediments

13. 2. Chemical Sedimentary Rocks
Water dissolves the minerals and they come out of the solution (precipitate)
The mineral crystals grow together to make the rock

14. Examples of Chemical Sedimentary Rock
Rock Salt (Halite)
When water in ocean water evaporates, leaving salt crystals behind

15. Examples of Chemical Sedimentary Rock
Limestone
MOST COMMON
Found in caves
Forms when calcium
carbonate precipitates from
a solution

16. 3. Bioclastic Sedimentary Rock
Made of things that were once living
Plant materials
Shells

17. Examples of Bioclastic Sedimentary Rock
Coal – made of plant remains
Coquina – made of shells

18. Know how to read this for the TEST!!

19. Identify the bioclastic sedimentary rock with the varied grain size.
Coal
Identify the clastic sedimentary rock with the clay grain size.
Shale
Identify the crystalline sedimentary rock with halite composition.
Rock Salt