Earth’s ocean crust thickened during glacial periods
DOI: 10.1063/PT.5.028624
Nature : During periods of extreme glaciation, so much water is sequestered in ice caps and glaciers that Earth’s sea level drops by 100 meters. The corresponding reduction in over-pressure exerted by seawater on the crust below is significant enough that it facilitates the production of ocean crust. That’s the conclusion reached by Richard Katz of Oxford University and his colleagues. The researchers investigated two areas of a mid-oceanic ridge, where new crust is created when magma wells up from the mantle below. The areas feature sequences of parallel hills whose separations imply that they formed at the maxima of the glacial cycles known as Milankovitch cycles. How exactly water pressure influences upwelling is unclear.