1. Chapter 4 - Rocks What can be learned by studying rocks…
We can learn mo better about earth.
So what is a rock???
It’s a mixture of 1 or more minerals. Easy.

2. The Rock Cycle
Shows how any rock may be transformed from one type into another.
It’s a continuous process that causes rocks to change.

4. Vocab terms Magma – underground molten rock
Lava – above ground molten rock
Crystallization – formation of minerals from cooling magma/lava
Weathering – any process that breaks down rocks into smaller pieces (sediment)

5. Vocab terms Erosion – transportation of sediment
Deposition – accumulation of sediment
Metamorphism – changing one type of rock into another by heat/pressure/chemicals
Lithification – compaction and cementation of sediment

6. Igneous Rocks…from fire
2 main types
Intrusive (large crystals)
From magma
Underground
Cools and forms slowly
Extrusive (small crystals)
From lava
Above ground
Cools and forms quickly

7. Igneous Rocks Classification
2 ways to classify igneous rocks
1 = Texture 2 = composition
1. Texture (3 types)
Coarse grained – slow cooling, large crystals
Fine grained – fast cooling, small crystals
Glassy – super fast cooling, glassy
Porphyritic – slow and fast cooling, has both large and small crystals

11. Andesitic (intermediate) Ultramafic
2. Composition
Granitic (felsic)
High in silica (SiO4), light colored, lower density
Basaltic (mafic)
Low in silica, dark colored, high in iron and magnesium higher density
Andesitic (intermediate)
Ultramafic

12. Sedimentary Rocks
Your teacher rocks!

13. Sedimentary Rocks From (Latin) sedimentum = settling
Made from sediments of any type
4 agents of erosion (transportation)
Water
Wind
Glaciers
Gravity

14. 3 Types Sedimentary Rock
Clastic = formed from sediment
Chemical = formed from precipitation or evaporation…dried up soda on a table
Biochemical (organic) = formed from remains of once living organisms

15. 1) Clastic Sedimentary Rocks
Conglomerate – rounded pebble sized
Breccia – angular pebble sized
Sandstone – sand sized
Siltstone – silt sized
Shale – clay sized

17. 2) Chemical Sedimentary Rocks
Crystalline limestone – precipitates from ocean water
Gypsum – precipitates from oceans, too
Travertine – precipitates in caves
Chert/flint – quartz
Rock salt – evaporated salt water

18. 3) Biochemical Sedimentary Rx
Fossil limestone – fossil remains
Coquina – shells and shell fragments
Chalk – microscopic shells and clay
Bituminous coal (B coal) – plant remains

19. Metamorphic Rocks Means to change form 2 types of metamorphism
1. Contact
- small areas from toughing hot magma
2. Regional
- large areas from the pressures of mountain building

20. Agents of Metamorphism
Heat (temperature)
Pressure (stress)
Reactions in hot solutions (chemicals)

21. Metamorphic Rock Classification
2 textures
Foliated - layered
Nonfoliated – not layered

22. 1. Foliated Metamorphic Rx
A) Slate – very thin layers from shale
Phyllite – thin layers, sheen, wavy, from slate
Schist – medium layers,shiny, micas, from phyllite
Gneiss – distinct black & white layers, from schist or granite

23. 2. Nonfoliated Metamorphic RX
Marble – shiny, fizzes in acid, H = 3, from limestone
Quartzite – shiny, won’t fizz, H = 6 – 7, from sandstone
Anthracite coal – shiny, black, from bituminous coal
The carbon cycle…see page 85

24. TREE
Igneous Rx
A) Intrusive