Given that the quantity of water in the mantle is thought to be equivalent to that in all the oceans (large drop), I'd presume not. The mantle-water research i

Given that the quantity of water in the mantle is thought to be equivalent to that in all the oceans (large drop), I'd presume not. The mantle-water research is fairly new, with this report from 2017: "There’s as much water in Earth’s mantle as in all the oceans" <https://www.newscientist.com/article/2133963-theres-as-much-water-in-earths-mantle-as-in-all-the-oceans/ https://www.newscientist.com/article/2133963-theres-as-much-...> The USGS detail pages are based on a 1993 publication, Igor Shiklomanov's chapter "World fresh water resources" in Peter H. Gleick (editor), Water in Crisis: A Guide to the World's Fresh Water Resources (Oxford University Press, New York). <https://www.usgs.gov/special-topics/water-science-school/science/how-much-water-there-earth https://www.usgs.gov/special-topics/water-science-school/sci...> and <https://www.usgs.gov/special-topics/water-science-school/science/where-earths-water https://www.usgs.gov/special-topics/water-science-school/sci...>