English Channel - Catastophic Origin?

"In places, this valley is more than seven miles wide and 170 ft deep, with vertical sides. Its nearest geological parallels are found not on Earth but in the monumental flood terrains of the planet Mars.

"This suggests the valley was created by a catastrophic flood following the breaching of the Dover Strait and the sudden release of water from a giant lake to the north."

Specifically, Dr Gupta's proposes that Britain and France were "linked by a high ridge of chalk hills, running roughly between Dover and Calais". Between 400,000 and 200,000 years ago, the aforementioned monster lake, "hundreds of feet above sea level", breached the chalk ridge and made good its escape towards the Atlantic. More

I always take dates with a pinch of salt, because of the many layers of assumptions used by orthodox scientists. This could be evidence for a cataclysm 10,000 years ago. Or of an earlier one....