Geological Processes

Lithosphere ( this is broken into 7 / 8 peices calles PLATES )

• a thin rocky Crust ( top layer 
• The mantle ( solid outer part underneath a liquid inner part
• The outer core and the inner core ( very hard, due to pressure ) 

• The noticed that africa and south america looked like 2 pieces of a jig-saw, the thought the 2 continents where once joined.
• He noticed the the same types of rock in africa and south america
• He found similar fossils of plants and animal on oppsite sides of huge oceans 

Alfred Wegener could not expain how the continents had moved 

The earths lithosphere is made up of huge slabs of rock called tectonic plates which are moving a few centimetres a year 

• Studies of the shape of the ocean floor ( which shows it has mountains and canyons, rather than being flat ) 
• New dating tecnology shows that the ocean floor was very young compared to the land 
• investigations into the magnetic properties of the rocks on the seabed ( this shows that the seabed is moving ) 

• slip past eachother ( earthquake ) 
• move towards eathother ( mountains and volcanoes ) 
• Move away for one another ( causes the release of ignous rock ) 

Plates slip past eachother 

when 2 plates slip past one another then tend to jerk, causing Earthquakes. 

• San Andreas Fault ( America ) 

Plates move towards eachother

If plates move towards eachother and they are of the same plate, neither with sink 

The force causes them to buckle upwards forming a new mountain

• Mount Everest and The Alps  

Plates move towards eachother 

when two different plates move together, continental plate ( found on land ) and oceanic crust ( found under water )

The oceanic crust is densier then the continental crust , resulting in the oceanic crust sinking. 

As the inside of the earth is hot, this plate melts forming magma, this process is called subduction

Plates move away for one another 

when plates move apart magma rises to the surface. The moltan rock quickly cools froming igneous rock

• Mid-Atlantic Ridge