Bathymetry Map (image) Imperial College London Share Print E-Mail Caption Bathymetry map of the Dover Strait showing prominent valley eroded through center of Strait. Note the rock ridge made of chalk in southern Britain and northern France which would have connected across Strait prior to breaching. Credit Imperial College London Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.