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| Grau-Crespo, R.; Ruiz-Hernández, S. E.; Ruiz-Salvador, A. R.; De Leeuw, N. H.. |
| We have investigated the thermodynamics of mixing between aragonite (orthorhombic CaCO3) and strontianite (SrCO3). In agreement with experiment, our simulations predict that there is a miscibility gap between the two solids at ambient conditions. All SrxCa1 xCO3 solids with compositions 0.12 < x < 0.87 are metastable with respect to separation into a Ca-rich and a Sr-rich phase. The concentration of Sr in coral aragonites (x 0.01) lies in the miscibility region of the phase diagram, and therefore formation of separated Sr-rich phases in coral aragonites is not thermodynamically favorable. The miscibility gap disappears at around 380 K. The enthalpy of mixing, which is positive and nearly symmetric with respect to x = 0.5, is the dominant... |
| Tipo: Journal Contribution |
Palavras-chave: 1246; Aragonite; Coral reefs; Thermodynamic activity; Strontium; Strontium. |
| Ano: 2010 |
URL: http://hdl.handle.net/1834/4103 |
