Objective Anhydrous mineral phases in the Earth's upper mantle may serve as a large internal reservoir of water that has profound implications for the Earth's evolution as a water planet.Water plays important roles in the phase transformation kinetics in the Earth's interior,which affects the mantle dynamics.However,the influence of water content in the major rock-forming minerals on
FAN DaweiKUANG YunqianXU JinguiZHANG BoXIE Hongsen
We report the results of a natural phenacite from 0 to 30.9 GPa using in situ angle-dispersive X-ray diffraction and a diamond anvil cell at the National Synchrotron Light Source, Brookhaven National Laboratory. Over this pressure range, no phase change or disproportionation has been observed. The isothermal equation of state was determined. The values of V0 , K0 , and K0 refined with a third-order Birch-Murnaghan equation of state are V0 =1116.1 ± 1.2 3 , K0 =223±9 GPa, and K 0 =5.5 ± 0.8. Furthermore, we confirm that the linear compressibilities (β) along a and c directions of phenacite are elastically isotropic (βa =1.50 × 10-3 and βc =1.34 × 10-3 GPa-1). Consequently, it can be concluded that the compressibility of phenacite under high pressures has been accurately constrained.
