1. GEOLOGY Explore how our Earth’s surface is constantly changing. OLD RAG, VA

2. What do you know?  What is the rock cycle?  What evidence do fossils give us about changes in the life on Earth over time?  What is meant by plate tectonics?  What do earthquakes and volcanoes have to do with plate tectonics?  What are weathering and erosion?  How do humans impact the Earth’s surface?

3. Rocks  Rocks are made of two or more different minerals that have been: a. cemented together a. cemented together b. squeezed and heated together OR b. squeezed and heated together OR c. melted and cooled together. c. melted and cooled together. Rocks move and change over time due to heat and pressure within the Earth and weathering and erosion at the surface. Rocks move and change over time due to heat and pressure within the Earth and weathering and erosion at the surface. These processes change rocks from one type to another. These processes change rocks from one type to another.

4. Classifying Rocks  Rocks have properties that can be observed, tested, and described.  Composition, grain size and textural features, color, and the presence of fossils help with rock identification.

5. Rocks’ Formation Rocks’ Formation  Rocks are classified by how they were formed.  Layers of minerals or organic matter deposited by water (sediment) that were cemented together are SEDIMENTARY ROCK.  Rocks that were melted and cooled are IGNEOUS ROCK.  Rocks that were changed by heat and pressure are METAMORPHIC ROCK.

6. The Story of 3 Rocks The Story of 3 Rocks Sedimentary Rock Granite: Igneous Rock Slate: Metamorphic Rock

7. The Rock Cycle The Rock Cycle

8. The Rock Cycle

10. Our Ancient Earth  Scientific evidence indicates that the Earth is 4.6 billion years old.  The age of rocks can be determined reliably.

11. Paleontologists are scientists who use fossils to study life in the past. There are many questions the fossil record can help us answer. Can you think of some?

12. Exploring the Fossil Record Exploring the Fossil Record (2.2 min) Exploring the Fossil Record  Early Complex Life: Invertebrates and early fish of the Paleozoic (1 min) Early Complex Life Early Complex Life  The Mesozoic Era: The age of the Dinosaur (1 min) The Mesozoic Era The Mesozoic Era  The Cenozoic Era: The age of Mammals (1.3 min) The Cenozoic Era The Cenozoic Era

13. FOSSILS  How do fossils form? (2.3 min.) How do fossils form? How do fossils form?  What do fossils tell us about the history of the Earth? (2 min.) What do fossils tell us about the history of the Earth? What do fossils tell us about the history of the Earth? Chesapecten jeffersonius from VA’s Coastal Plain. Coal from VA’s Appalachian Plateau Gingko from VA’s Piedmont Region

14. Composition of the Earth Our Earth is composed of four layers:  The CRUST CRUST  The MANTLE MANTLE  The INNER CORE The INNER CORE The INNER CORE  The OUTER CORE The OUTER CORE The OUTER CORE Pressure and temperature increase with depth beneath the surface.

15. PLATE TECTONICS PLATE TECTONICS  The Earth’s heat causes movement of material within the Earth.  Large continent-size blocks (plates) move slowly about the Earth’s surface, driven by heat.  The theory of Pangaea indicates that our 7 continents were once one giant continent. Pangaea

16. Earthquakes and Volcanoes  Most earthquakes and volcanoes are located at the boundary of plates (faults). earthquakes volcanoesearthquakes volcanoes  Plates can move together in convergent boundaries.  Plates can move apart in divergent boundaries.  Plates can slip past each other horizontally in sliding boundaries.

17. Geology of the Oceans Geology of the Oceans  Geological features in the oceans, including trenches and mid-ocean ridges are caused by current and past plate movements.  Plate movements also cause geological features on the continents, like mountains.

18. Weathering and Erosion Weathering and Erosion  Rocks and other minerals on the Earth’s surface are constantly being broken down both chemically and physically.  The products of weathering include clay, sand, rock fragments, and soluble substance.  Weathered rock material can be moved by water and wind and deposited as sediment.

19. Human Impact  Humans have a varying degree of impact on the Earth’s surface through their everyday activities.  With careful planning, the impact on the land can be controlled.