1. Sedimentary Rocks Lithification Sediments Deposition Transport Erosion Weathering

2. From Sediment to Rock • Most sedimentary rocks are formed through a series of processes: erosion, deposition, compaction, and cementation.

3. Weathering The sediments that make up sedimentary rocks are produced by: Mechanical & Chemical Weathering

4. Mechanical Weathering

5. Chemical Weathering

6. MineralStability

7. Products of Weathering • Lithic (Rock) Fragments(granite, basalt, schist, etc.) • Dissolved Ions(Calcium, Potassium, Sodium, etc.) • Rust Minerals(Hematite, Goertite, etc.) • Clay Minerals(Bentonite, Montmorillonite, etc.) • Residual Minerals(Quartz, Orthoclase, Muscovite, etc.)

8. Erosion & Transport Water Wind Ice Gravity

9. Deposition

10. Lithification Sediment Rock

11. Cementation • Typical Cement: • Calcite • Quartz

12. Sedimentary Rocks Identification Note: Use the same terms to describe sediments & sedimentary rocks. Only difference is lithification!

13. CompositionWhat minerals make up the rock? TextureWhat is the shape, size and orientation of the mineral grains that make up the rock?Major Difference:Crystalline vs. Clastic Rock Identification is based on:

14. Types of Sedimentary Rocks Detrital Rocks Chemical Rocks vs.

15. Difference: TextureDetrital (Clastic Texture)vs.Chemical (Crystalline Texture)

16. Detrital Rock Composition • Detrital Rocks • Lithic Fragments • Quartz • Clay Minerals • Fossil Fragments • Rust Minerals • Orthoclase • Muscovite / Biotite

17. Clastic Texture Grain Size Grain Sorting Grain Rounding Sediment Maturity Detrital Rock Texture

18. Grain Size • Gravel2mm • Sand1/16 mm • Mud - Silt1/256 mm • Mud - Clay

19. Detrital Rock Names(Based Primarily on Grain Size) Gravel Sized: Conglomerate Sand Sized: Sandstone Mud Sized: Mudstone Siltstone Shale

20. Sorting

21. Grain Roundness

22. Gravel Sized Detrital Rocks(Subdivided Based on Grain Roundness) Conglomerate Breccia

23. Maturity • Immature • Poorly Sorted • Angular grains • Mixed Compositionincluding clay • Mature • Well Sorted • Well Rounded • All Quartz

24. Sandstones(Subdivided based on maturity) Quartz Sandstone Arkose (Sandstone) Lithic Sandstone Greywacke

25. Sandstones Under a Scope

26. Detrital Sedimentary Rock ID

27. Crystalline Texture Coarse Fine Chemical Rock Texture

28. Chemical Sedimentary Rocks(Names based primarily on composition) • Composition • Calcite • Quartz (silica) • Halite • Gypsum • “Carbon” / Plant Remains • Basic Rock Name • Limestone • Chert • Rock Salt • Rock Gypsum • Peat or Coal

29. Chemical Rocks(Names based mainly on composition) Limestones Crystalline Limestone Fossiliferous Limestone Chalk

30. Chemical Rocks (cont.) Evaportites Chert Rock Salt Rock Gypsum Coal

31. Chemical Sedimentary Rock ID

32. Sedimentary Rocks on Earth