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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

Text of 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 BoundariesConvergent BoundariesTransform BoundariesLets break it downDivergent BoundariesPlace where 2 plates pull away from each other

How is the rock pulled at Divergent Boundaries?

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

This STRESS is called

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

A Normal Fault (fault is a break in Earths crust)

Rock drops down as it breaks

What happens next @ Divergent Boundaries?A geologic feature or eventMay form RIFT VALLEYS and FAULT BLOCK MOUNTAINS on continents

SEA-FLOOR SPREADING in the ocean

Helpful HintsDivergent 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

Convergent BoundariesPlaces where plates crash (or crunch) together or subduct (one sinks under)

How is the rock pushed at convergent boundaries?Rock is pressed or squeezed together.

This stress is called COMPRESSION

What happens when the rock is squeezed from the Stress of Compression?A REVERSE FAULTRock is forced upward as it is squeezed.

What happens next @ Convergent Boundaries?May form Mountain Ranges.These are Folded Mtns. Like the Himalayas or the Rockies.

FoldingFolding 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.

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Folded Mountains

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

What else happens @ Convergent Boundaries?Helpful HintsConvergent = Connecting boundaries Rock crunches up to make folded mountains.Rock goes down under @ subduction zone.

Transform BoundariesPlace where 2 plates slide past each other

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

What happens when the rock is sheared (or cut) from the Stress of Shearing?A STRIKE-SLIP FAULTRocks on each side of the fault slip past each other as they break.

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.

Helpful HintsShearing 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 Faulting

2424Normal

Reverse

Strike-Slip Fault

Can you match the boundary name correctly with its diagram?

_______________________________________Plate Boundaries: