1. Igneous Rocks Igneous rocks are the result of the solidification of magma or lava. – Magma – molten rock inside the earth – Lava – Molten rock outside the earth When molten rock cools, it crystallizes. – - molecules arrange themselves into an ordered pattern and form crystals

2. Classifying Igneous Rocks Rocks that form deep in Earth, from magma: – Show large crystals – Are called intrusive or plutonic rocks Rocks that form on Earth ’ s surface, from lava: – Show no crystals – glassy or vesicular (gas pockets) – called extrusive or volcanic rocks

3. Individual minerals

4. Vesicular (GAS POCKETS) Glassy Texture: Obsidian

5. Igneous Rock Class Igneous Rock formed in lava flows (above ground) Igneous Rock formed deep underground

7. A rock is igneous if it has… Large mineral crystals randomly arranged A glassy texture Many small holes or gas pockets

8. Exit Ticket: Why are these two rocks igneous? Rock A Rock B

9. Sedimentary Rocks Sedimentary rocks are composed the weathered remains of other rock. Most sedimentary rocks exist as a thin layer covering the Earth’s continents.

10. Sedimentary Rock Class

11. A rock is sedimentary if it has… Strata (layers) Fossils Different sediments (rocks) glued or cemented together

12. Exit Ticket: Why are these two rocks sedimentary? Rock A Rock B

13. Metamorphic Rocks Are formed from existing rock by the action of heat and pressure. Metamorphic rock is formed by the process of 1. regional metamorphism occurs when large areas of rock are placed under intense heat or pressure. 2. contact metamorphism Hot magma forces it way into overlying rock baking the rocks it comes in contact with.

14. Irregular look and wavy bands of minerals in Metamorphic Rock Metamorphic Rock Class

15. A rock is metamorphic if it has… Mineral crystals arranged in alternating dark and light bands (banding) Thin, flaky layers (foliation) A distorted texture

16. Igneous Rock formed in lava flows (above ground) Irregular look and wavy bands of minerals in Metamorphic Rock Metamorphic Rock Class

17. Irregular look and wavy bands of minerals in Metamorphic Rock Metamorphic Rock Class

18. Exit Ticket: Why are these two rocks metamorphic? Rock A Rock B