Our new paper has been published on Geochimica et Cosmochimica Acta. This research utilized the huge dataset of chemical composition of the Pacific deep-sea sediments. We revealed that there are "excess" K and Mg in deep-sea sediments originated from seawater and showed that their uptake rates have decreased from the early Cenozoic to modern. If the K and Mg from seawater were taken up into a marine authigenic clay via a reverse weathering reaction, the result may indicate a decline in reverse weathering over the Cenozoic.