High-pressure orthorhombic ferromagnesite as a potential deep-mantle carbon carrier.

ABSTRACT: Knowledge of the physical and chemical properties of candidate deep-carbon carriers such as ferromagnesite [(Mg,Fe)CO₃] at high pressure and temperature of the deep mantle is necessary for our understanding of deep-carbon storage as well as the global carbon cycle of the planet. Previous studies have reported very different scenarios for the (Mg,Fe)CO₃ system at deep-mantle conditions including the chemical dissociation to (Mg,Fe)O+CO₂, the occurrence of the tetrahedrally-coordinated carbonates based on CO₄ structural units, and various high-pressure phase transitions. Here we have studied the phase stability and compressional behavior of (Mg,Fe)CO₃ carbonates up to relevant lower-mantle conditions of approximately 120 GPa and 2400 K. Our experimental results show that the rhombohedral sid

SUBMITTER: Liu J 

PROVIDER: S-EPMC4284511 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature