1. Chapter 6 Section 3 Sedimentary Rock

2. Formation Sediment (small particles of sand, clay, or pebbles) get cemented together.

3. Cementation Natural cements are carried in the ground water: Silica, from quartz Calcium carbonate, from calcite Iron oxides

4. Cementation Cement used concrete is powdered limestone! (a sedimentary rock)

5. Sediments Three types of sediments: Clastic sediments Chemical sediments Organic sediments

6. Clastic Sediments Made from weathered rock or mineral fragments. Classified by size (texture): Clay – small sized Sand – medium sized Pebble – large sized

7. Clastic Sementary Rocks Breccia (sharp fragments) & conglomerate (rounded fragments) (p. 200) Pebble sized fragments (2 mm or more)

8. Clastic Sedimentary Rock Sandstone: Made of sand-sized particles, usually quartz. Surface feels like sandpaper. Mudstone: Made of particles smaller that sand. See Figure 6-18 (p. 201)

9. Clastic Sedimentary Rocks Degree of rounding of fragments and type of cementation is also part of their rock history.

10. Chemical Sediments Come from minerals once dissolved in sea water. Salts in sea water form sedimentary rock at the bottom of the ocean.

11. Chemical Sedimentary Rocks Evaporites: formed when substances dissolved in water are left behind as the water evaporates. Rock Salt and Rock Gypsum Great Salt Lake, Utah

12. Chemical Sedimentary Rocks Precipitates: form when dissolved substances precipitate, or fall out of solution. Compact Limestone: Calcite precipitates out of sea water. Chert (flint): Silica precipitates out of sea water.

13. Organic Sediments Remains of once-living organisms (shells or plants). Many may contain fossils.

14. Organic Sedimentary Rocks Organic Limestone: forms from remains of animals such as corals. Buried Plants Lignite (Brown Coal) Bituminous Coal Heat & Pressure

15. Uses Shale & silt: used for sewer pipe, drain time, & chimney linings. Rock Gypsum: drywall & plaster Sandstone: component in glass Porcelain is a combination of clay, feldspar, & quartz sand. Fiberglass insulation & computer chips are made from sand. White house: made of sandstone.