1. Unit 17 STRUCTURE OF THE EARTH

2. What are the different types of rocks? IGNEOUS ROCKS formed from molten rocks (magma) that flow to the Earth’s surface (lava) when a volcano erupts comes from the word “ignite” meaning fire

3. 2 Types of Igneous Rocks INTRUSIVE IGNEOUS formed underground or beneath the Earth’s surface formed when magma cools and solidifies slowly have large crystals and are coarse-grained because the crystals have enough time to grow to a large size ex. - granite

4. EXTRUSIVE IGNEOUS formed on the Earth’s surface formed when lava cools and solidifies quickly have smaller crystals and are fine-grained because they do not have enough time to grow in size ex. - basalt

5. EXAMPLES OF IGNEOUS ROCKS GRANITE BASALT

6. SEDIMENTARY ROCKS formed when grains or “sediments” of weathered rocks (rocks broken into smaller pieces by different physical and chemical means) are pressed and cemented together by dissolved minerals may contain fossils ex. – sandstone, limestone, shale, conglomerate, breccias

7. LIMESTONE SANDSTONE SHALE

8. FORMATION OF FOSSILS fossils are remains of animals and plants that lived long ago preserved in sedimentary rocks

9. METAMORPHIC ROCKS formed when igneous and sedimentary rocks change their structures under intense heat and pressure comes from the word “metamorphosis” which means change ex. – slate, from sedimentary shale rock - marble, from sedimentary limestone rock - schist, from igneous basalt rock

10. EXAMPLES OF METAMORPHIC ROCKS SCHIST GNEISS

11. ROCK CYCLE

12. STRUCTURE OF THE EARTH

13. CRUST thinnest, top layer between 0-50 km thick made up of many separate pieces called plates forms the Earth’s surface or the ground

14. MANTLE beneath the crust made up of molten rocks called magma (formed due to high temperatures beneath the mantle) makes up the greatest volume of the Earth’s structure (about 2900 km thick)

15. CORE innermost layer which is very hot made up of solid iron and nickel the core’s heat causes the rocks in the mantle to be in the liquid state

16. http://www.ontariogeoscience.net/keyconceptitems/rockcyle.jpg http://mulch.cropsoil.uga.edu/soilsandhydrology/images/Granite.jpg http://www.imageafter.com/dbase/images/nature_extinct/b20nature_extinct0 05.jpghttp://www.imageafter.com/dbase/images/nature_extinct/b20nature_extinct0 05.jpg