The formation of strait was through scouring by erosion. It had for many millennia (since the last warm interglacial) been a land bridge that linked the Weald in Great Britain to the Boulonnais in the Pas de Calais. Though pitted by troughs and rivers, the English Channel was almost mainly land at the height of the last ice age. The predominant geology of both and of the seafloor is chalk. Although somewhat resistant to erosion, erosion of both coasts has created the famous white cliffs of Dover in the UK and the Cap Blanc Nez in France. The Channel Tunnel was bored through solid chalk – compacted remains of sea creatures and marine-deposited, ground up calciferous rock/soil debris.
the formation of strait was through scouring by erosion it had for many millennia (since the last warm interglacial) been a land bridge that linked the weald in great britain to the boulonnais in the pas de calais though pitted by troughs and rivers the english channel was almost mainly land at the height of the last ice age the predominant geology of both and of the seafloor is chalk although somewhat resistant to erosion erosion of both coasts has created the famous white cliffs of dover in the uk and the cap blanc nez in france the channel tunnel was bored through solid chalk – compacted remains of sea creatures and marine-deposited ground up calciferous rock/soil debris