Melting and decomposition of MgCO3 at pressures up to 84 GPa

作者：Solopova N A^*; Dubrovinsky L; Spivak A V; Litvin Yu A; Dubrovinskaia N

来源：Physics and Chemistry of Minerals, 2015, 42(1): 73-81.

DOI：10.1007/s00269-014-0701-1

• Mg-carbonate melting
• High-temperature decomposition boundary
• Phase relations
• High-pressure experiment
• Laser heating
• Raman spectroscopy

Magnesium carbonate MgCO3 (magnesite) was experimentally studied at pressures of 12-84 GPa and temperatures between 1,600 and 3,300 K. We applied the high-pressure technique using a multianvil press and a diamond anvil cell with laser heating. The phase relations and melting of magnesite were investigated by means of Raman and time-resolved multi-wavelength spectroscopy. Magnesite is found to melt congruently within the entire studied pressure range at temperatures of 2,100-2,650 K. At temperatures above 2,700 K, we observed decomposition of magnesite with formation of MgO and a carbon phase (diamond). Our results demonstrate that at high pressures, the magnesium carbonate melt can exist at a wide range of thermodynamic conditions.

• 出版日期2015-1