Apatite fission-track analysis of samples covering a 4.2-kilometer vertical section from the western flank of Vinson Massif, Antarctica's highest mountain, indicates that the Ellsworth Mountains were uplifted by 4 kilometers or more during the Early Cretaceous following the initial separation of East and West Gondwana and accompanying the opening of the Weddell Sea. Relief of at least 1.8 kilom...