1. 1.Review key concepts of time, plate tectonics, and the rock cycle. 2.Recognize the relationships and interconnectedness of the various processes. 3.Review water as a resource. 4.Utilize a physical model to demonstrate a component of the hydrologic cycle. OBJECTIVES

2. Battle of the Heat Engines

3. Earth is a dynamic planet. Earthquakes Volcanoes Erosion by water, wind and ice These processes require ENERGY Battle of the Heat Engines

4. Earth has two Heat Engines. The Internal Heat Engine Source: Radioactive decay Drives Plate Tectonics Convection Cells in Mantle

5. Battle of the Heat Engines The External Heat Engine Source: Solar radiation Drives the Hydrologic Cycle Convection in the atmosphere

6. Battle of the Heat Engines The continual battle between these two Heat Engines describes a process of building up and wearing down of Earth’s crust.

7. Battle of the Heat Engines The Hydrologic Cycle Describes the movement of water around Earth. Evaporation Condensation Transportation Precipitation Infiltration Evapo-Transpiration Runoff (Drain-a-Nation)

8. Battle of the Heat Engines

9. The Rock Cycle Describes the transformation of one rock type to another via various processes. Utilizes both Heat Engines to accomplish this work.

10. Battle of the Heat Engines Three Rock Types: Igneous – “Fire Formed” Formed from molten material Sedimentary – “Settling” Formed from weathered rocks Metamorphic – “Change Form” Formed from other rocks using various “agents”

11. Battle of the Heat Engines Rocks “transformed” by the agents of: Melting Metamorphism (heat, pressure, chemically active fluids) Weathering

12. Battle of the Heat Engines A Simplified Diagram of the Rock Cycle

13. Battle of the Heat Engines

14. Weathering Chemical – Rocks broken down into smaller pieces of something different. Mechanical – Rocks broken down into smaller pieces of the same stuff. Weathered materials can be eroded, transported, deposited, and lithified to become new sedimentary rocks.

15. Battle of the Heat Engines Geologic Time Many geologic processes require vast amounts of time (aka Deep Time). Earth is 4.6 Billion years old. At one second per year, a movie of Earth’s history would last about 145 years!

16. Battle of the Heat Engines Problem: We don’t have that kind of time to wait for geologic events to happen… …but we can attempt to build models that simulate real world situations and speed up the clock.

17. Battle of the Heat Engines Physical Models: Allow for repeatability Speed up geologic processes Can have variables altered to test for changes in results Provide hands-on experience

18. Battle of the Heat Engines The River Cutters Model G reat E xplorations in M ath and S cience