Theory of Plate Tectonics Continental Drift The geological
- Slides: 23
Theory of Plate Tectonics
Continental Drift • The geological theory by Alfred Wegner that states that Earth’s continents were once ONE large landmass “Pangea” and over time the continents slowly moved apart. • Evidence. . . ▫ Shape of the Earth’s continents They look like they fit together like pieces of a puzzle
Continental Drift • This theory was NOT CORRECT!!
Plate Tectonics • The geological theory by Tuzo Wilson that states that pieces of Earth’s lithosphere are in constant slow motion. • Evidence ▫ The SAME FOSSILS on different continents ▫ Magnetic patterns found on the ocean floor at along a mid-ocean ridge.
Plate Tectonics – Lithosphere • Lithosphere ▫ Top layer of the Earth which contains the “plates” • Asthenosphere ▫ Partially molten layer of Earth right below the Lithosphere. ▫ There are convection currents in the Asthenosphere that slowly move Earth’s plates (the Lithosphere)
Lithosphere and Asthenosphere Convection Currents in the asthenosphere
Earth’s Plates – Boundary Map
3 Types of Boundaries 1. Transform 2. Divergent 3. Convergent
Transform Boundaries • 2 plates slide past each other, moving in opposite directions • Along these boundaries, crust is neither created or destroyed • Earthquakes occur here • Faults are created
Divergent Boundaries • 2 plates slide apart or diverge • Forms rift valleys and mid-ocean ridge • Sea-floor spreading occurs here
Divergent Boundaries Sea-Floor Spreading Rift valley
Convergent Boundaries • 2 plates slide together or converge • Results in a collision ▫ Denser crust will be on the bottom (oceanic crust) • Usually forms mountains, volcanoes, trenches, and a subduction zone
Convergent Boundaries Subduction Zone The denser plate (oceanic) will go into the Earth Volcano Trench
1. Which boundary is this?
2. Which boundary is this?
3. Which boundary is this?
4. Which boundary is this?
5. Which boundary is this?
6. Which boundary is this?
7. Which boundary is this?
8. Which boundary is this?
9. Which boundary is this?
Plate Tectonics vs. Continental Drift Plate Tectonics Plates are moving. Theory by: Tuzo Wilson Continental Drift Move Continents are moving. Theory by: Alfred Wegner
- Continental drift
- Plate tectonics vs continental drift
- Convergent plate boundary
- Plate tectonics vs continental drift
- Compare continental drift and plate tectonics
- 7 lithospheric plates
- Converging continental plate and oceanic plate oreo
- Continental drft
- Earths mantle
- Continental drift
- Kesler science plate tectonics
- Continental drift theory
- Proof of continental drift theory
- Proof of continental drift theory
- Continental drift theory
- Continental drift theory slideshare
- Wegners theory of continental drift
- Evidence of the theory of plate tectonics
- The plate tectonics theory states that:
- Summarize the theory of plate tectonics
- Lithosphere definition
- Unifying theory of plate tectonics
- Theory of plate tectonics
- Section 1 continental drift