divergent boundaries convergent boundaries transform boundaries

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There are 3 types of Plate Boundaries. Each one has a type of STRESS on the rock & a way that it breaks, called a FAULT :. Divergent Boundaries Convergent Boundaries Transform Boundaries. Let’s break it down…. Divergent Boundaries. Place where 2 plates pull away from each other. - PowerPoint PPT Presentation

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Page 1: Divergent Boundaries Convergent Boundaries Transform Boundaries
Page 2: Divergent Boundaries Convergent Boundaries Transform Boundaries
Page 3: Divergent Boundaries Convergent Boundaries Transform Boundaries
Page 4: Divergent Boundaries Convergent Boundaries Transform Boundaries

There are 3 types of Plate Boundaries.

Each one has a type of STRESS on the rock

& a way that it breaks, called a FAULT:

• Divergent Boundaries• Convergent Boundaries• Transform Boundaries

Let’s break it down…

Page 5: Divergent Boundaries Convergent Boundaries Transform Boundaries

Divergent Boundaries• Place where 2 plates pull away from each other

Page 6: Divergent Boundaries Convergent Boundaries Transform Boundaries

How is the rock pulled at Divergent Boundaries?

Rock gets THIN in the middle as it is pulled apart.

This STRESS is called

Page 7: Divergent Boundaries Convergent Boundaries Transform Boundaries

What happens when the rock SNAPS from the Stress of Tension?

A Normal Fault (fault is a break in Earth’s crust)

Rock drops down as it breaks

Page 8: Divergent Boundaries Convergent Boundaries Transform Boundaries

What happens next @ Divergent Boundaries?

• A geologic feature or event…

May form RIFT VALLEYS and FAULT BLOCK MOUNTAINS on continents

SEA-FLOOR SPREADING in the ocean

Page 9: Divergent Boundaries Convergent Boundaries Transform Boundaries

Helpful Hints…• Divergent is like “dissecting” or “dividing”

• If you pull warm bubble gum or silly putty, it will thin in the middle until it is stressed so much that it breaks.

• Happens on land & under H2O

Page 10: Divergent Boundaries Convergent Boundaries Transform Boundaries
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Convergent Boundaries

• Places where plates crash (or crunch) together or subduct (one sinks under)

Page 12: Divergent Boundaries Convergent Boundaries Transform Boundaries

How is the rock pushed at convergent boundaries?

• Rock is pressed or squeezed together.

• This stress is called COMPRESSION

Page 13: Divergent Boundaries Convergent Boundaries Transform Boundaries

What happens when the rock is squeezed from the Stress of Compression?

• A REVERSE FAULT• Rock is forced upward as it is squeezed.

Page 14: Divergent Boundaries Convergent Boundaries Transform Boundaries

What happens next @ Convergent Boundaries?

• May form Mountain Ranges.These are Folded Mtns. Like the Himalayas or the Rockies.

Page 15: Divergent Boundaries Convergent Boundaries Transform Boundaries

Folding– Folding occurs when rocks are compressed or deformed and they buckle under

the stress.

– The diagram below illustrates how rocks fold.

The crest of the fold, where the rock layers slope downward form the anticline.

The valley of the fold where the layers slope toward the lower axis form the syncline.

Page 16: Divergent Boundaries Convergent Boundaries Transform Boundaries

Folded Mountains

Page 17: Divergent Boundaries Convergent Boundaries Transform Boundaries

• May form Volcanoes @ Subduction Zones as denser oceanic plate dives under less dense continental plate.

What else happens @ Convergent Boundaries?

Page 18: Divergent Boundaries Convergent Boundaries Transform Boundaries

Helpful Hints…• Convergent = “Connecting” boundaries – Rock crunches up to make folded mountains.– Rock goes down “under” @ subduction zone.

Page 19: Divergent Boundaries Convergent Boundaries Transform Boundaries

Transform Boundaries• Place where 2 plates slide past each other

Page 20: Divergent Boundaries Convergent Boundaries Transform Boundaries

How is the rock broken at Transform Boundaries?

• Rock is pushed in two opposite directions (or sideways, but no rock is lost)

• This stress is called SHEARING

Page 21: Divergent Boundaries Convergent Boundaries Transform Boundaries

What happens when the rock is sheared (or “cut”) from the Stress of Shearing?

• A STRIKE-SLIP FAULT• Rocks on each side of the fault slip past

each other as they break.

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What happens next at Transform Boundaries?

• May cause Earthquakes when the rock snaps from the pressure.

• A famous fault @ a Transform Boundary is the San Andreas Fault in California.

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Helpful Hints…

• Shearing means cutting (“Shears” are like scissors)

• Transform boundaries run like trains going past each other in different directions & they shake the ground! San Andreas

Fault, CA

Page 24: Divergent Boundaries Convergent Boundaries Transform Boundaries

Faulting

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Page 25: Divergent Boundaries Convergent Boundaries Transform Boundaries

Normal

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Reverse

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Strike-Slip Fault

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Can you match the boundary name correctly with its diagram?

A._____________B._____________C._____________

Plate Boundaries: