As politicians begin to disentangle the UK from Europe, scientists have revealed how Britain’s first “Brexit” unfolded almost half a million years ago.
In the throes of an Ice Age, a vast glacial lake north of a land bridge that connected Britain to Europe started to overflow.
When the lake burst its banks, a surge of water destroyed the bridge, paving the way for a megaflood that carved out the Dover Strait.
The study, published in Nature Communications, describes how the scientists made the discovery.
Two decades ago, engineers building the Channel Tunnel found holes in the seabed of the English channel.
According to the study, fresh analysis of those holes shows they hold clues to how the so-called “geological Brexit” developed.
The scientists believe they formed as plunge pools pummelled by water cascading over an escarpment.
Professor Sanjeev Gupita, co-author of the study, said: “The breaching of this land bridge between Dover and Calais was undeniably one of the most important events in British history, helping to shape our island nation’s identity even today.
“Without this dramatic breaching Britain would still be a part of Europe. This is Brexit 1.0 – the Brexit nobody voted for.”
The researchers haven’t yet been able to create an exact time of the events. They are now hoping to extract samples of sediment in the plunge pools, which should offer an insight into the timing of the erosion.
It won’t be an easy task. The mission will require researchers to juggle powerful tidal changes and the world’s busiest fishing lane.