Science Behind Natural Disasters

Earthquakes

Earthquakes are vibrations caused by rocks breaking under stress.

The outer layer of the Earth is called the crust. The crust is broken into different parts called tectonic plates. These plates are constantly moving, and continents are attached to the plates which causes them to move as well. The movements are so gentle that we can’t feel them.

An earthquake occurs when two of these plates collide. Minor earthquakes are a result of two plates brushing up against each other. Major earthquakes are created when one plate is forced under another.

Tsunamis

A tsunami is a group of large waves caused by a sudden movement on the ocean floor. A tsunami often follows an earthquake, underwater landslide, volcanic eruption or meteor.

Friction between two tectonic plates causes seismic energy (vibrations), which causes an earthquake to occur. When an undersea earthquake happens it abruptly pushes one of the tectonic plates upwards. This causes an immense displacement of ocean water, causing it to spread out every direction from the centre of the earthquake. As the waves get closer to shore they get compressed into a smaller space causing them to gain height.

Volcanic Eruption

A volcano is a vent that acts as a passage for molten rock to travel from the mantle to the Earths surface, Magma sits in the mantle, as the magma rises through rock gas bubbles form and expand, the build up of pressure causes the magma to break through the main vent and secondary vents of the volcano. Once magma is passed through the cracks it is then called lava. Volcanic eruptions have different extremity's, the level of power depends on the amount of gas. The more gas bubbles the magma has, the more power it exits the earth with.