Plate TectonicsMs. Clark12.10.11

Has the Earth always looked like this?

Let’s Discuss…

VocabularyThese words can are in the

video…

•Pangaea•Theory of plate tectonics•Continental drift•Sea floor spreading•Convection currents•Subsidence•Boundary•Convergent boundary•Divergent boundary•Transform boundary•Rift•Ridge•Trench•Fault•Theory •Subduction zone

The Effects of Plate Tectonics Video

The Effects of Plate Tectonics VideoThe most powerful source that alters the earths surface is the movement of tectonic plates.

Tectonic plates are large, solid pieces of earths lithosphere that move in different directions on top of a hotter flowing layer of the asthenosphere

Wegener theory, called continental drift, explained why identical animal fossils like that of mesorausaus were found on coastlines separated by vast oceans.

The continental drift theory could also explain the matching of large geological features across continents.

Sea floor spreading in turn was the first positive proof that there was a force strong enough to move continents. This was the thing needed to verify Wegners theory.

Plate tectonic theory explains how earth works

Heat from earths interior, creates convection currents which move the lithospheric plates around in different directions and different speeds.

Plate boundary- the place where two or more plates meet

Faults are cracks in the earths crust that tilt slightly outward from one another

The Effects of Plate Tectonics Video

A convergent boundary is when two tectonic plates move toward or push against each other.

When an oceanic plate converges with a continental plate, the denser oceanic plate slides beneath the lighter continental plate, into the asthenosphere called the subduction zone.

The tectonic force that pushes the plates together causes the plunging oceanic plate to pull the continental plate down is called a trench.

Subduction zone is where most of the volcanoes are formed.

The ring of fire is where magma erupts through volcanoes and numerous earthquakes erupt. About 90% of world earthquakes form here

Transform boundaries slide past each other, resulting in a large fault. (Earthquakes)

Folded mountains, trench and subduction zones are formed at the convergent boundary.

Mid ocean ridge, Rift Valley and fault block mountains are located at divergent boundaries.

Pangaea PuzzleWhat is Pangaea?

•Pangaea or Pangea is from the Greek origin and means “All Lands”

•The continents shown on the Pangea Puzzle are not to scale. •They are in the approximate location of the present day continents.•You will be forming the supercontinent, Pangaea. •Pangaea existed approximately 225-260 million years ago.

QUIZTomorrow 12.13.12