1. 4-3 Sedimentary Rock—usually forms under water
notice the layers
(stratification)

2. From Sediment to Rock
Formed from sediments=small, loose solid pieces of material that come from weathered rock or living material
formed in layers (may not be visible)
May contain fossils
examples of sediments:
shells, bones
mud, gravel
sand, clay

3. How do sediments build up?
Observe how sediments are deposited (website)

4. Sediments accumulate in layers at the bottoms of lakes or oceans (called deposition)

5. (examples—not to memorize)
sand becomes……………sandstone
gravel becomes………….conglomerate
mud & clay becomes…….shale

6. 2 forces that make the sediments into rocks (can take millions of years)
2--Cementation
dissolved minerals crystallize and glue particles together (natural glue)
(GLUED TOGETHER)
1--Compaction
press sediment together and squeezes out the water
(PRESSURE)

7. PERFORMANCE TASK #4

8. Texture of Sedimentary Rocks

9. 3 types of sedimentary rocks (look at the type of sediment)
1--clastic
2--organic
3--chemical

10. Clastic=broken pieces glued together (need to look at size of pieces)
Shale
tiny pieces of clay
thin, flat layers
feels smooth
due to compaction
Sandstone
forms on beaches, ocean floors, in riverbeds, or sand dunes
fairly small pieces of sediment
due to compaction & cementation
Conglomerate and Breccia
variety of particle sizes
conglomerate=round
breccia= sharp edges

11. 2 other types of sedimentary rocks
Organic-from ancient plants and animals {many extinct-may have fossils}
coal=remains of swamp plants (over millions of years old)
limestone=from shells and skeletons of ancient sea animals, which contain calcite (coral, clams, oysters, snails)
Chemical Rocks
limestone forms when dissolved calcite comes out of solution and forms crystals
rock salt and gypsum form from evaporation (in dry climates)

12. Performance Tasks Number FIVE and EIGHT…
Can now be completed
Make sure you completed 5 & 8!

13. Questions What natural activities work to break down rock? weathering
What do sand and mud become when they form sedimentary rock?
Sandstone, shale and mudstone
In what type of rock would paleontologists look for fossils?
(organic) sedimentary –like limestone

14. Question--{enrich}
A layer of a sedimentary rock is 2 meters (2000 mm) thick. How many years did it take for this layer to form if an average of 4mm of sediment accumulated each year?
>> 500 years