1. Mt. Fuji
Use with Session 6: Field Work in Nepal

2. Smoky Mountains

3. Himalayan Mountains

4. Age of Mountains?

5. Plate Boundaries

6. Transform Plate Boundaries - occur where one plate slides by another plate horizontally.

8. This leads to folding or to one plate sliding under another.
Convergent Plate Boundaries - occur where two plates move together in slow collisions.
This leads to folding or to one plate sliding under another.

13. Divergent Plate Boundaries - occurs where two plates are moving apart, leaving a gap.
Magma fills the gap between the plates creating a mountain ridge.
As the plates move farther apart, a rift valley is created between two ridges.

15. Rift Valley

16. New Madrid
The New Madrid Seismic Zone (pronounced /nuː ˈmædrɪd/), sometimes called the New Madrid Fault Line, is a major seismic zone and a prolific source of intraplate earthquakes (earthquakes within a tectonic plate) in the southern and midwestern United States, stretching to the southwest from New Madrid, Missouri.

17. The faults responsible for the New Madrid Seismic Zone are embedded in a subsurface geological feature known as the Reelfoot Rift that formed during the breakup of the supercontinent Rodinia in the Neoproterozoic Era (about 750 million years ago). The resulting rift system failed to split the continent, but has remained as an aulacogen (a scar or zone of weakness) deep underground, and its ancient faults appear to have made the Earth's crust in the New Madrid area mechanically weaker than much of the rest of North America.

19. Undersea Volcano Eruptions Caught on Video

20. The formation of the planet generated heat from gravitational energy and the decay of radioactive elements, which are still present today. Heat released from Earth’s core drives convection currents throughout the mantle and the crust.

23. Convection Currents
Heat from the core and the mantle causes convection currents in the mantle.

26. Drifting Continents

27. Continental Drift
In 1910 German scientist Alfred Wegener hypothesized that all the continents were once joined together in a single landmass (Pangaea) and have since drifted apart.

28. Wegener used evidence from different scientific fields to support his ideas about continental drift.

29. Evidence from Land Features.
Appalachian Mountains run across eastern North America and disappear off coast of Newfoundland. Then the similar mountains reappear in the British Islands and Scandinavia.
Mountain ranges on the continents of Africa and South America line up.

30. Evidence From Fossils
Fossils of ancient organisms have been found on widely separated landmasses. Leading Wegener to infer that these organisms lived on a single landmass.

31. Evidence From Climate
Deep scratches show that continental glaciers once covered South Africa but it’s climate is too mild today for continental glaciers to form. During same time period large tropical swamps found in North America and Europe.

34. Wegener’s Hypothesis Rejected
Geologist rejected Wegener’s ideas because he could not explain the forces moving the continents.

35. Harry Hess’s theory of sea-floor spreading.
The sea floor spreads apart along both sides of a mid-ocean ridge as new crust is added. As a result, the ocean floor carries the continents along with them.

36. Evidence of Hess’s theory
Molten material erupting along mid-ocean ridges.
Magnetized stripes found on ocean floor.
Age of rocks increase as distance from ridge increases.

37. Magnetic Striping

39. The theory of Plate Tectonics
In 1965 J. Tuzo Wilson combined what geologist knew about sea-floor spreading, Earth’s plates, and continental drift into a single theory.

40. Theory of Plate Tectonics
1. The Earth’s lithosphere (crust and upper mantle) is made of solid, rigid rock.
2. The lithosphere is broken into a dozen or more sections of varying sizes called “plates.”

41. Theory of Plate Tectonics
3. Convection currents in the asthenosphere move the plates in different directions on the surface of the Earth.
4. The moving plates cause massive geological changes, including earthquakes, mountain building, and volcanic activity.

42. Subduction
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.

43. Land forms are created through a combination of destructive processes (weathering, glaciers and erosion) and
constructive processes (crustal deformation/folding and faulting, volcanic eruptions, new sea floor forming along ocean ridges and deposition of sediment.)

44. Folding, faulting and uplifting can rearrange the rock layers so the youngest is not always found on top.

45. What to study for test?
*Notes *Diagrams *Articles *OAA Test Questions (Rocks & Plate Tectonics) *Quizzes *Lab activities in Science Journal *Maps of Plate Tectonic