The rock cycle is a concept used to explain how the three basic rock types are related and how Earth processes, over geologic time, change a rock from one type into another. Plate tectonic activity, along with weathering and erosional processes, is responsible for the continued recycling of rocks.
1.
2. The Life of a Rock Layers of sediment join together. Igneous Sedimentary Rock Changes are made Melted rock cools from pressure and and hardens heat. Metamorphic
3. Rocks become smaller, and smaller, and smaller, and ... smaller • By erosion • By wind • By earthquake • By floods • By rain • By slides • By man
4. Terms to Know • Weathering: the breaking up of rocks and soil • Erosion: the moving of weathered rock and soil. Weathering allows erosion to take place.
5. Products of Weathering • Clay • Sand • Rock Fragments (pebbles and stones)
6. Rocks change………….. • By earthquakes • By volcanoes • By heat and pressure
7. Sedimentary Rock is . . . • Rock formed when layers of small particles of shell, rock, and sand join together.
8. Sedimentary Rocks How They are Made • Wind and water break down the earth • Bits of earth settle in lakes and rivers • Layers are formed and build up • Pressure and time turn the layers to rock
9. Types of Sedimentary Rocks Sandstone Limestone Gypsum Conglomerate Shale
10. Fossils • Fossils are usually found in sedimentary rock and are the remains or imprints of plants and animals that died long ago.
11. Fossils-Life From the Past • Fossils provide information about life and conditions of the past. • Scientific evidence shows that the Earth is approximately 4.5 billion years old
12. Metamorphic Rock is . . . • Rock that is formed when pressure and heat create changes to sedimentary or igneous rock.
13. Metamorphic Rocks What are They? • Rocks that have changed • They were once igneous or sedimentary • Pressure and heat changed the rocks
14. Types of Metamorphic Rocks Schist Gneiss
15. Igneous Rock is . . . • Rock that is formed when melted rock cools and hardens.
16. Igneous Rocks What are They? • Fire Rocks • Formed underground by trapped, cooled magma • Formed above ground when volcanoes erupt and magma cools
17. Types of Igneous Rocks Granite Scoria Pumice Obsidian
18. Review of the Rock Cycle • How are sedimentary rocks formed? • What is a fossil? • How are metamorphic rocks formed? • How are igneous rocks formed? • Give an example of each type of rock. • What is weathering? • Explain what erosion is.
19. Credits • These slides were a compilation of work by: • Jefferson County Schools Power Points on Rocks • http://jc-schools.net/PPTs-science.html • Ellen Benegar (Suffolk Public Schools)