资源环境科技发展态势分析平台

Nominally anhydrous minerals (NAM) such as olivine are important reservoirs for water in the Earth’s upper mantle, although the association of water with crystallographic defects is poorly understood. Here, hydrated regions at the atomic scale in fayalite (Fe₂SiO₄) are directly resolved using atom probe tomography. Site-specific analyses reveal regions that are either compositionally homogenous or contain nanometer-long channels that are consistent with hydrated defects. Na as a minor element is also enriched within the interlayers, indicating the formation environment is associated with Na geochemically. The ability to directly visualize and characterize hydrated regions at the nanometer scale can provide critical insight into the material properties of NAM and their impact on planetary-scale processes, such as the influence of water-bearing minerals on mantle rheology and geodynamics.