The Theory of Plate Tectonics Earth’s crust is made of many ________ These plates move as a result of ______________ in the mantle Earth’s surface is constantly being _____________by these movements Earthquakes, volcanoes, rifting and mountain building all result from the process of ________________.

“ Continental Drift” ________________– German scientist Continents have not always been in their present locations All continents were once part of a __________ - ________ called _________ Also only one great ocean called ______________

EVIDENCE TO SUPPORT CONTINENTAL DRIFT Puzzle-Like fit of the continents Fossil Evidence Matching Geologic Features Evidence of Climate Change

___________________

The Movement of ________

CONVECTION Convection is ___________ motion and the transfer of heat resulting from heating and __________ differences Lithospheric plates move as a result of ____________ in the mantle Convections cells in the ______________ rotate slowly over millions of years. Because the convections cells rotate in different directions, the ____________ move in different directions also

Plate _______________ Where two plates _______ a plate boundary is formed. What happens at a plate boundary depends on the _________ each plate is moving and the density of each plate Earth’s surface is constantly being __________ by these movements Earthquakes, volcanoes, rifting and __________ _________ occur at or near plate boundaries. Plate movements also cause ________ that affect areas along the boundary and within the ___________itself.

Type of Plate Boundaries Plate boundaries are classified into three main groups based upon the relative _____________ of movement –______________ Plate Boundary: plate move towards each other –_____________ Plate Boundary: plate move apart –______________ Boundaries: plate slide past each other (side by side)

Convergent Boundaries There are three types of convergent boundaries classified the type of crust involved: –Continent to continent convergence –Ocean to continent convergence –Ocean to ocean convergence

The Himalayan Mountains, Including Mt. Everest, formed as a result of the convergence of the Indian and Asian Plates __________________________

Island arc volcanoes and deep ocean trenches form at ocean crust to ocean crust convergent boundaries _________ - _______ boundaries:

Ocean crust to continental crust convergent boundary. Because oceanic crust is more dense than continental crust, the ocean crust is subducted __________ - ________ boundaries:

_____________ Zones When two plates of different __________ collide at a convergent boundary, the denser plate is driven _______ the less dense _______ forming a subduction zone ________ is generated in the subduction zone resulting in the formation of volcanic arcs.

Transform Boundaries When two plates _____ past each other a _________ boundary is formed. Earthquakes are _________ along transform boundaries because the plates do not slide __________ past each other

The San Andreas fault is an example of a Transform Boundary

__________ Boundaries When two plates move apart a _________ boundary is formed. Mid-Ocean Ridges and ____ ______form at __________ boundaries

New ocean crust is created at mid- ocean ridges. These are also referred to as spreading centers

Iceland is a volcanic island that has formed on top of a Mid- Atlantic ridge