Lithospheric Plates

The outer shell of the Earth, known as the lithosphere, is not one continuous piece but is broken into several large and small pieces called ‘lithospheric plates’ or tectonic plates [The earth’s crust consists of several large and some small, rigid, irregularly-shaped plates (slabs) which carry continents and the ocean floor]. These plates fit together much like a jigsaw puzzle, and they float atop the semi-fluid asthenosphere beneath them.

Movement Of The Plates

1.Magma Movement: The main reason these plates move is the movement of the molten magma beneath them in the asthenosphere. The magma is heated by the Earth’s core, becomes less dense, rises, and then cools and sinks again, creating a convection current. This movement is often referred to as mantle convection.

2.Plate Movement: As a result of this convection in the mantle, the plates on top move. The movement is gradual, averaging a few millimetres to a few centimetres per year, depending on the plate and location.

Types Of Earth Movements And Forces

1.Endogenic Forces: These are forces that originate from within the Earth and are responsible for various earth movements. These can be slow, such as the movement of tectonic plates or sudden like earthquakes and volcanic eruptions.