The document discusses the three main types of rocks: igneous, sedimentary, and metamorphic rocks. It describes the rock cycle whereby rocks constantly change from one type to another through geological forces. Igneous rocks form from molten rock and can be intrusive or extrusive. Sedimentary rocks form through the compaction and cementation of sediments and can be clastic or non-clastic. Metamorphic rocks form from heat and pressure acting on existing rocks, either through contact metamorphism near magma or regional metamorphism during tectonic activity.

1. ROCKS AND THE
ROCK CYCLE
Department of Civil Engineering
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2. Contents
 Rock Cycle
 Types Of Rocks
 Igneous Rock
 Sedimentary Rock
 Metamorphic Rock
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3. Rock Cycle
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4. Rock Cycle
 Geologic forces cause rock to constantly change from one type to
another
 Complete the rock cycle diagram by adding the appropriate
processes that connect each rock type to the others .
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5. Rock Types 5

6. Major Types Of Rocks
 Igneous Rocks
 Sedimentary Rocks
 Metamorphic Rocks
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7. Igneous Rocks
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8. Igneous Rock
 Latin word “ignis” means
“fire”
 Igneous rock is formed from
molten rock that hardened into
a solid state
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9. Types Of Igneous Rock
 Intrusive Igneous Rock
 Extrusive Igneous Rock
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10. Intrusive Igneous Rock
 Igneous rocks that form below
the Earth surface
 Magma cools slowly over
millions of years deep beneath
the Earth surface.
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11. Extrusive Igneous Rock
 Igneous rock that has formed
on the Earth surface
 It forms when lava cools
quickly on the Earth’s surface.
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12. Characteristic Of Igneous Rocks
Composition:
 It is the mineral content
 It often shown as color of rock
Texure:
 Size and arrangement of
mineral crystals
 Igneous crystals often
interlocking
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13. Examples
 Andesite
 Basalt
 Obsidian
 Diorite
 Granite
 Gabbro
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14. Sedimentary Rocks
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15. Sedimentary Rock
 Latin word “Sedimentum”
which means “settling”
 Sedimentary rocks are products
of mechanical and chemical
weathering.
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16. Classification Of Sedimentary Rock
 Clastic
• Discrete fragments and particles
• All detrital rocks have a dastic texure
 Non-Clastic
• Pattern of interlocking crystals
• May resemble an igneous rock
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17. Clastic
Conglomerate Red Sand Stone Shale
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18. Non-Clastic
Lime Stone Halite Chert
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19. Examples
 Shale
 Breccia
 Dolomite
 Sandstone
 Limestone
 Conglomerate
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20. Metamorphic Rocks
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21. Metamorphic Rocks
 Greek word “Metamorphic”
which means “to change form”
 Metamorphic rocks are formed
of heat and pressure
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22. Formation Of Metamorphic Rock
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23. Types Of Metamorphic Rock
Contact Metamorphism:
 Formed when magma pushes throw
existing rock
 Changes the structure and mineral
composition of surrounding rock
Regional Metamorphism:
 Metamorphism sometimes occurs
with tectonic plate movement
 Tremendous heat and pressure is
created at plates edge
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24. Examples
 Slate
 Marble
 Gneiss
 Schist
 Quartzite
 Amphibolite
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