5. S EDIMENTARY R OCKS Form when sediments (bits and pieces of any other rocks) are compacted and cemented together. **Normally layered**

6. S EDIMENT The following processes are necessary for the formation of sediment: 1. Weathering – breaking down of rock material by physical or chemical means 2. Erosion - The transportation of weathered sediment by water, wind, ice, etc.

7. T HE FOLLOWING PROCESSES ARE NECESSARY FOR THE FORMATION OF SEDIMENTARY ROCK : 3. Deposition – dropping off of sediment - Usually occurs in a body of water (oceans). - This happens when the agent of erosion slows down or stops 4. Compaction – Squeezing of sediment by the weight of overlying sediment - Results in de-watering

8. 5. Cementation - gluing together of sediment by minerals - Quartz or calcite is dissolved in water, when the water leaves the sediment, the minerals remain gluing the sediment together. - This process is called lithification

9. T WO CLASSES OF SEDIMENTARY ROCKS CLASTIC AND CHEMICAL Clastic rocks are made up of pieces of other rocks. Chemical rocks are made from evaporation of water or chemicals precipitating out of water

10. C LASTIC R OCKS Classified based on particle size Clay, silt, sand, pebbles, cobbles, boulders Made of mostly quartz, feldspar, and clay minerals But, composition does not matter (for clastic rocks)

14. C HEMICAL R OCKS May have crystalline texture Classification based on composition – (made of a single mineral)Grain size does not matter Dissolved minerals precipitate out of water and are called “evaporites”

17. B IOCLASTIC ( LIFE - PIECES ) Made mostly of fossils, shells, or organic material

20. E VAPORITES Steps for evaporite formation 1. Minerals dissolve in water (weathering) 2. Water evaporates (deposition) 3. Dissolved minerals precipitate out leaving salt minerals behind. (cementation) Precipitation is the opposite of dissolution

21. This is Ancient Lake Bonneville. A massive salt water lake was once at this location. The lake eventually evaporated away and left a massive salt deposit

25. S EDIMENTARY S TRUCTURES STRATIFICATION - sediment layers are stacked on top of each other. The Grand Canyon in AZ is a perfect example.

26. S EDIMENTARY S TRUCTURES RIPPLE MARKS - are produced by flowing water or wave action

27. Sedimentary Structures Fossils – evidence of past life. Only found in sedimentary rocks

28. I KNOW IT IS A SEDIMENTARY ROCK BECAUSE 1. It has fossils (organic remains) 2. It has pebbles 3. It has clasts 4. It is layered