Plate Techtonics

  • Continental Drift- states that cintinents have moved
  • Pangaea- all lands
  • Panthalassa- all seas
  • Mid-Atlatic Ridge- an undersea mountain range with a steep, narrow valey running down its center
  • The earths crust consists of two types, Oceanic crust and continental crust
  • convergant boundry is when the direct colision of one plate with another
  • A divergent boundary occurs at the point where two plates are moving away from each, creating more crust at the point of separation.
  • The trnasform boundary forms where two plates are grinding past eachother.
  • THe convection Current caused by the expansion of a liquid, solid, or gas as its temperature rises. The expanded material, being less dense, rises, while colder, denser material sinks.
  • Convection is a mode of heat transfer which includes the movement of the molecules of the material.
  • Sea-floor spreading is the process in which the ocean floor is extended when two plates move apart.  As the plates move apart, the rocks break and form a crack between the plates.  Earthquakes occur along the plate boundary.  Magma rises through the cracks and seeps out onto the ocean floor like a long, thin, undersea volcano

The Theory of Plate Techtonics

Plate techtonics is the theory explaining geologic changes that result from the movment of lithosheric plates over the asthenosphere. the earths atmosphere is made up of plates and move in all directions.

They all contain different movements and what the plates do and how mountains and stuff like that are formed

convection currents are when the two different water tematures go up or down warm water rises and cold water falls

Continental Drift

1.alfred believed that the continenets where once together in one big land mass called pangaea


2.Alfred wegners hypothosis says that evidence of changes in climatic patterns added strength to his hypothisis. evidence proves that there have been glaceirs in places to hot for there to be one like in africa and there are fossils of plants that dont grow in places

3. A trench has occured and magna starts rising out of it and it starts to create new rock on the sea floor and starts pushing on both sides of the trench and the yoccur because of undersea valcanos