Calcite-Aragonite Equilibrium at 100{degrees}C

Area of Science:

• Geochemistry
• Mineral Physics

Background:

• Calcite and aragonite are polymorphs of calcium carbonate.
• Understanding their phase transition is crucial for geological and materials science applications.

Purpose of the Study:

• To precisely determine the equilibrium pressure of the calcite-aragonite transition.
• To compare experimental results with existing literature data.

Main Methods:

• High-pressure and high-temperature experimental techniques were employed.
• Phase transition equilibrium was identified through precise pressure and temperature measurements.

Main Results:

• The equilibrium pressure for the calcite-aragonite transition was found to be 4.35 kilobars at approximately 100°C.
• Experimental data corroborate earlier findings on this phase transition.

Conclusions:

• The determined equilibrium pressure provides a reliable data point for the calcite-aragonite transition.
• Discrepancies with the most recent Simmons and Bell study highlight the need for further investigation into high-pressure phase equilibria.