Lesson 3 Reading Guide - KC

1. Sedimentary Rocks • How do sedimentary rocks form? • What are the three types of sedimentary rocks? Lesson 3 Reading Guide - KC

2. Sedimentary Rocks • compaction • cementation • clastic rock • clast • chemical rock • biochemical rock Lesson 3 Reading Guide - Vocab

3. Sedimentary Rock Formation • Mineral and rock fragments can be transported by water, glacial ice, gravity, or wind. • The sediments eventually are deposited, or laid down, where they can them accumulate in layers. Lesson 3-1

4. Sedimentary Rock Formation(cont.) • The weight from the layers of sediment forces out fluids and decreases the space between grains during a process called compaction. • Compaction can lead to a process called cementation. Lesson 3-1

5. Sedimentary Rock Formation(cont.) • When minerals dissolved in water crystallize between sediment grains, the process is called cementation. • Mineral cement holds the grains together. Lesson 3-1

6. Sedimentary Rock Formation(cont.) What is the difference between compaction and cementation? Lesson 3-1

7. Sedimentary Rock Identification • Sedimentary rocks that are made up of broken pieces of minerals and rock fragments are known as clastic rocks. • The broken pieces and fragments are called clasts. • Sediment size alone cannot be used to determine the environment where a clastic rock formed. Lesson 3-2

8. Sedimentary Rock Identification(cont.) clastic from Greek klastos, means “broken” Lesson 3-2

9. Sedimentary Rock Identification(cont.) • When water becomes saturated with dissolved minerals, particles can crystallize out of the water and form minerals. • Chemical rocks form when minerals crystallize directly from water. Lesson 3-2

10. The water that once filled this lake bed was saturated with dissolved halite. The water evaporated and crystalline rock salt formed. National Geographic/Getty Images Lesson 3-2

11. Sedimentary Rock Identification(cont.) • Biochemical rock is a sedimentary rock that was formed by organisms or contains the remains of organisms. • Sometimes the remains or traces of organisms are preserved as fossils in biochemical rock. Lesson 3-2

12. Sedimentary Rock Identification(cont.) Chemical and biochemical sedimentary rocks are common on Earth’s surface. Lesson 3-2

13. Sedimentary Rock Identification(cont.) How do chemical and biochemical sedimentary rocks form? Lesson 3-2

14. A clastic sedimentary rock is made of clasts of minerals or rock fragments. • When minerals crystallize directly from water, a chemical sedimentary rock results. • A biochemical sedimentary rock contains the remains of living organisms or was formed by organisms. National Geographic/Getty Images Lesson 3 - VS

15. During which process does the weight from layers of sediment force out fluids and decrease the space between grains? A. cementation B. crystallization C. compaction D. evaporation Lesson 3 – LR1

16. Which types of rocks are sedimentary rocks made up of broken pieces of minerals and rock fragments? A. chemical C. fragmented B. biochemical D. clastic Lesson 3 – LR2

17. Chemical rocks form when minerals crystallize directly from which of these? A.gas B.water C.sediment D.magma Lesson 3 – LR3

18. Do you agree or disagree? 5. Water can dissolve rock. 6. All sedimentary rocks on earth formed from the remains of organisms that lived in oceans. Lesson 3 - Now