As the edges of these plates move against one and other the Cause Mountains, volcanoes and earthquakes. Sudden movements of the tectonic plates are of which cause the more dangerous ones. This is because of the sudden jerk caused between them.
Primary Plate:
- African Plate
- Antarctic Plate
- Eurasian Plate
- Indo-Australian Plate
- North American Plate
- Pacific Plate
- South American Plate
Secondary Plates:
- Arabian Plate
- Caribbean Plate
- Cocos Plate
- Juan de Fuca Plate
- Nazca Plate
- Philippine Sea Plate
- Scotia Plate
The crust is a very thin layer made from the plate tectonics around the Earth, its equivalent in deepness from Liverpool to Manchester around 70km deep. The Mantle of Earth is chemically divided into layers, between the mantle and the crust it is viscous (a thick liquid). Earths mantle is a rocky surface and consists of 84 percent of the planets volume. The inner core of Earth is a solid layer that has a average temperature of around 5500 degrees Celsius. Scientists believe that the inner core consists of iron nickel. Because the Earths inner core is not structured with Earths mantle, it has a possibility that it moves freely. The growth of the inner core is believed to be a vital part of the Earths magnetic field.
The Earths plate are made from broken parts of the earths crust because of the heat inside that rise and then fall, this creates convection currents which causes the plates to move. When the plates move towards the earths crust the plates will move apart but when the plates move towards each other is called current converge, the movement and activity within the earths crust in referred to as the plate tectonics. A point in which two plates meet is known as the plate boundary, these plate boundaries are which may form to create earthquakes and Volcanoes, this is why such disasters are more likely to occur closer to the boundary’s.
Different types of plates have different patterns of movement;
- A Tensional, constructive and divergent boundary is when plates move apart
- A Compressional, destructive and Convergent boundary is when the plates move closer to each other.
- A conservative, transform boundary is when plates meet either side of each other and often make sudden jerks against each other this can be the cause of earthquakes.
Constructive Boundaries are plates that move apart, these plates move away because of radio active decay in the earth’s core which causes hot circular conventions which are the cause for the movement of tectonic plates. The plates move very slowly but can cause a huge amount of damage still, Often the Magma from inside deep inside will rise then begin to be accompanied by an earthquake. This Magma then solidifies upon the surface and then becomes Igneous Rock, this will occur repeatedly over time, eventually over time the rock will build up will becoming a volcano.
Under the sea volcanoes have been discovered this is because the plates beneath the sea bed are constructive boundaries it has been known for some volcanoes to have erupted within the sea. As shown in the diagram below:
I am now going to discuss a compressional boundary which is when the plates move towards each other, usually consists of a continental plate and oceanic plate. Because the Oceanic plate is much denser in comparison to the Continental plate they move forwards as the oceanic plate is pushed beneath the continental plate this is called Subduction, Whilst the oceanic plate is forced beneath the continental plate it slowly begins to melt, when this have melted it will become Magma. By now the Magma will be of an extreme temperature, and will slowly begin to gather entering the chamber which is the space between either plates were the both met. Because the magma is under such pressure and is of a high temperature it will then begin to forced through cracks of the continental plate this could then cause a volcanic eruption as the pressure from the Magma will have built up, so when it escaped through the cracks such pressure it also released with the Magma too.
This can be seen through the diagrams below:
Then the continental plates begins to push upwards against each other FOLD MOUNTAINS can be formed through this process, mountains of which can be of a great size. When two continental plats push are forced against each other this is called folding. Fold mountains are parts of the earths crust which are forced together through compressional forces, the crust will become bent as the plates are then uplifted and forced together to form Mountains.
An earthquake caused through the plate tectonics can occur mainly were the plate boundaries are as stated, all forms of movement from the plates such as diverging, converging and transforming. This is caused through a sudden release of energy form the earths crust or mantle. Because of the friction between both plates the effects and vibrations are can be very strong and dangerous. This is called seismic waves which the vibrations of these can be measured through the magnitude of the waves.
