Control of Sea Level relative to the Continents

Abstract

IN my article on the isotopic evolution of the Earth¹ the presence of epicontinental seas at numerous times during the past 2 billion yr and the nearly constant thickness of Pre-Cambrian cratons throughout the world, regardless of age, were considered indicative of approximately constant ocean depth, and consequently constant ocean and continental crust volumes throughout geological time. No doubt the limitations imposed by this evidence are inexact and changes of the order of 10 per cent would be permissible, but it seems that the overall impression of constant volume is a permissible premise for discussions of changes in sea level.