Water is thought to have been present on Earth’s surface for most of geological time, but it disappeared from the surface of Mars soon after the planet’s formation. Jon Wade and co-authors quantify the relative volumes of water that could be removed from each planet’s surface via the burial and metamorphism of hydrated mafic rocks from the crust. They show that the metamorphic mineral assemblages in Martian lavas, which are richer in ferrous oxide than are Earth’s lavas, can hold about 25% more water. These assemblages are able to transport water to greater relative depths within the interior of Mars. The existence of a buoyant mafic crust and hotter geothermal gradients on Earth probably reduced the potential for upper mantle hydration early in geological history, leading to water being retained close to its surface.
- The divergent fates of primitive hydrospheric water on Earth and Mars (Letter p391, doi: 10.1038/nature25031)
- Martian water stored underground (News & Views p339, doi: 10.1038/d41586-017-08670-y)
Recent Hot Topics
- Sep 13Effect of rising sea levels on coastal wetlands
- Sep 6Sub-lethal effects of sulfoximine pesticides on bumblebees
- Aug 30Forecasting the locations of earthquake aftershocks
- Aug 23Splicing together a lineage from snapshots
- Aug 16Reducing yeast chromosome numbers has only minor effect on cell fitness
Sign up for Nature Research e-alerts to get the lastest research in your inbox every week.