Britain's Billion Year Journey

Rodinia - the first supercontinent

Between one billion and 620 million years ago, the continental crust that would one day be known as Britain formed tiny parts of a giant supercontinent called Rodinia (approximately 500 million years before the formation of Pangaea, a later supercontinent). All of Britain was south of the equator, with some parts as far as 60 degrees, further than Australia and the southernmost tip of South America today. The rifting or splitting apart of this supercontinent began around 760 million years ago to form a second supercontinent continent known as the ‘Vendian’ supercontinent.

Britain in two parts

Rifting of this second land mass caused the formation of a small ocean called the Iapetus. The split was complete by 550 million years ago. On the west side of the Iapetus Ocean was the continent Laurentia (now North America) and on the east side was a land mass called Gondwana (South America, Africa, Asia and Australasia). Split between these land masses was ‘Britain’. The northern part of Britain including Scotland was on the continent of Laurentia, and the Southern part of ‘Britain’ was on the continent of Gondwana. It was another 100 million years before Southern Britain and Scotland would finally meet…

A segment of Gondwana including Britain and Ireland, split away from the main body of Gondwana 475 million years ago. This land called Avalonia made its way across the newly formed Iapetus Ocean, eventually meeting with Laurentia about 440 million years ago. During parts of this transition, the continental crust, which makes up Britain, was underwater. By this time the continents had migrated across the globe and Britain was now approaching the equator.

Following in the wake of Avalonia was the giant landmass Gondwana, slowly approaching Laurentia and closing up the Iapetus Ocean. When this was complete 300 million years ago, Pangaea, the most recent Supercontinent was formed. Britain was fully enclosed in the middle of Pangaea by 250 million years ago. There was an ocean separating most of Africa from Europe and Asia called the Tethys. Up until now the continents were unrecognisable, but following the break up of Pangaea 140 million years ago, just as the dinosaurs were reaching great diversity, the earth started to resemble something we might recognise today. Britain, however, was part of an archipelago or series of islands. It was once again mostly under water. The Atlantic Ocean began to form as North America broke away from Europe, and by 80 million years ago South America and Africa separated too. At the same time, Africa and Europe became conjoined closing up the Tethys Ocean.

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