1. Rocks
Charity I. Mulig

2. Definition
Rocks are any solid mass of mineral or mineral-like matter occurring naturally as part of our planet.
Rocks are often made of several different minerals.

3. The Value of Rocks Rock is an important natural resource.
Used by early humans to make tools such as hammers, spears, knives, and scrapers.
Used for centuries to make buildings, roads, and monuments.
Certain types of rocks have helped build ancient and modern civilizations.
Rock study has helped scientists to discover the history of life on Earth.

4. Types of Rocks
Igneous rock is formed by the crystallization of molten magma.
Sedimentary rock is formed from the weathered products of preexisting rocks that have been transported, deposited, compacted, and cemented.
Metamorphic rock is formed by the alteration of pre-existing rock deep within Earth (but still in the solid state) by heat, pressure, and/or chemically active fluids.

5. The Rock Cycle

6. Igneous Rocks

7. Formation of Igneous Rocks
Intrusive igneous rocks are formed when magma hardens beneath Earth’s surface.
Extrusive igneous rocks are formed when lava hardens.

8. Classification of Igneous Rocks

9. Fine-Grained Igneous Rock
Coarse-Grained Igneous Rock
Glassy- textured Obsidian
Porphyritic Igneous Rock

10. Sedimentary Rocks

11. Formation of Sedimentary Rocks
Process
What happens?
Weathering
rocks are broken down by water, air, and living things.
Erosion
rocks are transported from one place to another
Deposition
rock fragments are dropped when agents of erosion losses energy
Compaction
rock fragments are squeezed together
Cementation
dissolved minerals are deposited in the tiny spaces among the sediments
* Compaction and cementation are collectively called lithification.

12. Classification of Sedimentary Rocks

13. Examples
Shale with Fossils
Conglomerate

14. Metamorphic Rocks

15. Formation of Metamorphic Rock
Metamorphism means “to change form.”
occur at elevated temperatures and pressures
Conditions for formation are found a few kilometers below the Earth’s surface and extend into the upper mantle.

16. Agents of Metamorphism
Heat provides the energy needed to drive chemical reactions.
Pressure produces more compact rocks with greater density.
Hydrothermal Solutions are hot water-based solutions escaping from the mass of magma which promotes recrystallization by dissolving original minerals and then depositing new ones

17. Types of Metamorphism Contact Metamorphism Regional Metamorphism
occurs when magma moves into rock.
Occurs near a body of magma
Changes are driven by a rise in temperature
results in large-scale deformation and high-grade metamorphism.
Directed pressures and high temperatures occur during mountain building.
Produces the greatest volume of metamorphic rock

18. Classification of Metamorphic Rocks

19. Sources of Heat and Pressure

20. Examples
Banded Gneiss
Non-Foliated Marble

21. Pictures Igneous Rocks Sedimentary Rocks
Sedimentary Rocks
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Metamorphic Rocks
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