Warm UP12 / 03/ 12•Give the three sources of evidence to support the theory of Continental Drift

Tectonic Plates have boundaries

3 Types of Boundaries1.Divergent boundaries2.Convergent boundaries3.Transform boundaries

DIVERGENT BOUNDARIES

Occurs where plates move apart

Most of these boundaries are found in the oceans

CONVERGENT BOUNDARIES

Occurs where plates push together

Can be Oceanic to Oceanic, Oceanic to Continental, and Continental to Continental

CONTINENTAL – CONTENENTAL COLLISION

• Occurs where two plates carrying continental crust push together.

• Both crusts are the same density.• This collision forms Mountain Ranges

Oceanic-Oceanic Subduction• Subduction – when one plate sinks beneath

another• This occus where one plate with oceanic crust

sinks, under another plate with oceanic crust• Forms deep ocean trenches and island arcs

Oceanic – Continental Subduction

• Occurs when ocean crust sinks under continental crust

• Forms deep-ocean trenches and coastal mountains

TRANSFORM BOUNDARIES

• Occurs where plates scrape past each other• Occurs mostly on the sea

floors near mid-ocean ridges• Example of one on land is the

San Andreas Fault in California