A continent is a large landmass, while continental drift refers to the movement of continents around the world over millions of years, resulting from the motion of tectonic plates (large rocky pieces) that make up the crust of the Earth.

For the first hundred million years from its birth, Earth was covered with endless seas of molten lava until it cooled down enough for a rocky surface. Soon after, vapours from rampant volcanoes condensed into water, and the crust soon drowned under permanent oceans¹. Water may have come from icy comets crashing into Earth as well.

Beneath the rocky cover, however, a soft but solid rock kept slowly flowing, cracking the crust into large rocky pieces – tectonic plates² – and began to move them around. In plate boundaries, the first landmasses started to rise from the oceans as magma deep within Earth found a way upwards, creating volcanic islands which eventually grew into continents (4 BYA – 2.5 BYA).

Many times since then, due to continental drift, continents laying on tectonic plates have got together only to be ripped apart, while new oceans have opened before shrinking and disappearing all alone.

Once again, some 300 million years ago, continents teamed up into one enormous landmass – Pangaea – surrounded by a vast ocean – Panthalassa. Animals and plants could roam freely, even to walk from pole to pole (in theory). Yet, the never-ending motion deeper inside our planet continued to move tectonic plates in different directions, starting to tear Pangaea in pieces around 200 million years ago.

Over time, the continents we are familiar with – Asia, Africa, North America, South America, Antarctica, Europe, and Australia – came into being and continued drifting into their current locations. Tectonic plates and continents lying on them keep moving up to a few centimetres a year, and it is predicted that after the next 250 million years, there will once again be only one vast continent on Earth.

Besides continental drift, the tectonic plates and their movements help explain many natural, sometimes destructive, phenomena.

Volcanoes often exist near plate boundaries because molten rock from deep within Earth can find a way upward at these intersections. Earthquakes are likely to occur at the sites where two plates slide past each other or collide. Colliding also forms mountains as the crust of the Earth crumbles and is pushed upwards. In some cases, however, one plate is forced underneath another. If this occurs on the seafloor, ocean trenches, some of the deepest places on Earth, can form.

¹ The first seas probably came into being some 4.4 billion years ago, but since the high temperatures of early Earth, water may have been nearly or entirely lost more than once during the first few hundred million years.

² The rocky crust of the Earth, including the seafloor, comprises seven or eight large tectonic plates and several smaller ones. Tectonic plates float on the flowing but solid rock of the mantle, which encapsulates the two-part core of our planet: a molten outer core and a solid inner core.

Bibliography

Dartnell, L. 2019. Origins How the Earth Shaped Human History. London, United Kingdom: Penguin Random House. 346 p. ISBN 9781784705435. Pages 8-9, 103-104.

Frankopan, P. 2023. The Earth Transformed an Untold History. London, United Kingdom: Bloomsbury Publishing. 695 p. ISBN 9781526622563. Pages 34-35.

Osman, J. 2019. The Little Book of Big Explorations Adventures into the Unknown That Changed Everything. London, United Kingdom: Michael O'Mara Books Limited. 272 p. ISBN 9781789290790. Pages 52-53, 131-134.

Rutherford, A. 2014. Creation The Origin of Life. London, United Kingdom: Penguin Books. 272 p. ISBN 9781780229072. Page 55.

Panciroli, E. 2022. The Earth a Biography of Life The Story of Life On Our Planet Through 47 Incredible Organisms. London, United Kingdom: An Hachette UK company. 255 p. ISBN 9781529413984. Pages 10-11, 16, 20, 108-109, 244.

Boyle, R. 2024. Our Moon a Human History. London, United Kingdom: Hodder & Stoughton. 313 p. ISBN 9781529342789. Page 34.

National Geographic Education. Plate Boundaries. Available at: https://education.nationalgeographic.org/resource/plate-boundaries/ (Accessed: 23 July 2023).

National Geographic Education. Plate Tectonics. Available at: https://education.nationalgeographic.org/resource/plate-tectonics/ (Accessed: 23 July 2023).

DK. 2021. Science the Definitive Visual Guide. London, United Kingdom: Dorling Kindersley. 520 p. ISBN 9780241446331. Page 434.

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