Effects of crystal structure and pressure on CaCO3 decomposition are investigated under reducing conditions.
Graphite formation out of CaCO3 is instantaneous nucleation at 2.5 GPa and 950°C.
Deep carbonate may undergo saturated decomposition under reducing conditions of the upper mantle.
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Representative x-ray diffraction patterns of the recovered samples from high P-T experiments
Representative optical and SEM images of the samples recovered from high P-T experiments at 2.5 GPa and 950°C
Representative Raman spectra of the recovered samples from high P-T experiments
Representative weight loss curves from TGA measurements on
The evolution of decomposition fraction of calcium carbonate with time at 2.5 GPa and reducing conditions