1. What events lead to the formation of
Warm Up 10/18/16
What events lead to the formation of
sedimentary rocks?

2. What is a Rock? Naturally occurring solid aggregate of minerals
Earth’s outer solid layer, the lithosphere, is made of rock
Three types: Igneous, Sedimentary, and Metamorphic

3. Types of Rocks
Igneous– form from solidification of molten (liquid) rock material. Most common rock in crust.
Sedimentary– form from compaction and cementation of sediments. Common on surface.
Metamorphic– form from re-crystallization of existing rock material. 3

5. How is Sedimentary Rock Formed?
Weathering
Erosion
Deposition
Burial
Lithification – sediments compact under pressure and gradually become solid rock

6. 3 Main Classes of Sedimentary Rocks
Clastic Sedimentary – formed from clastic sediments
Chemical Sedimentary – formed from minerals precipitated from water
Organic – formed from the remains of once- living things

7. Sedimentary Rocks
Clastic Sedimentary- sedimentary rocks formed from layers
Conglomerate

8. Clastic Sedimentary
Clast refers to a fragment of rock that was broken from a larger rock
Clastic rocks are composed of these clasts.
Clastic metamorphic rocks include breccias formed in faults
Clastic igneous rocks include some volcanic rocks – the ones broken by flow, injections or explosive disruption of lavas.
Breccia= clastic sedimentary rock that are composed of large angular fragments.

9. clay silt sand gravel conglomerate sandstone siltstone shale sediments
sedimentary
rocks
conglomerate
sandstone
siltstone
shale

10. Breccia Rock
Rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix
Formed by debris flows, avalanches, mud flows

11. Shale
Fine-grained, clastic sedimentary rock composed of flakes of clay minerals and other tiny fragments.
Formed during the compaction part of the rock cycle.

12. sorting Sandstone Chapter 6 Sedimentary rocks
Detrital sedimentary rocks
Sandstone
sorting
degree of similarity in particle size
Very poorly-sorted
Very well-sorted
moderately sorted

13. Chemical Sedimentary- sedimentary rocks formed from mineral pools after water has evaporated
Halite
Hematite

14. Salinas Grandes, Argentina
Evaporites

15. Organic Sedimentary- sedimentary rocks formed from the remains of once- living things.
Coal

16. Limestone
Most abundant organic sedimentary is limestone. Shells of marine organisms (coral reefs) settle to bottom of ocean forming thick layers of carbonate sediment.
Through burial and lithification, it is formed into limestone.

17. Discussion
Why do chemical sedimentary rocks form primarily in areas that have high rates of evaporation?

18. Talk It Over
What are some of the commercial values of sedimentary rocks?

19. Think It Over In Your Group What are the four main agents of erosion?
Discuss how each of these factors transport rock fragments to new locations.

20. Glacier

21. Moving Water

22. Wind

23. Gravity