More than 27 billion tons of river sediments enter our oceans each year. Probably the rate of sediment transport is diminishing as looser topsoil is removed and as erosion smooths out Earth’s terrain. Even if erosion has been constant, the sediments now on the ocean floor would have accumulated in only 30-million years. No process has been proposed which can remove 27-billion tons of ocean sediments each year. So, the oceans cannot be hundreds of millions of years old.a