The Lithosphere and Tectonic Plates
- As mentioned previously, the lithosphere incorporates the upper mantle and crust.
- The lithosphere is composed of several large fragments called tectonic plates.
- These plates are able to move independently, albeit very slowly, due to being dragged by convection currents in the asthenosphere.
- The movement of tectonic plates causes geological events such as earthquakes and volcanoes as plates collide, move apart or slide past each other.
- It also results in continental drift – the gradual movement of continents over very long periods of time.
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The lithosphere is divided into tectonic plates which move independently due to convection currents in the asthenosphere.
(Image: M.Bitton, Wikimedia Commons)