Chemical diffusion coefficients in natural enstatite were measured at 850 to 1250C under 1atm. Rutherford back-scattering spectrometry was used to measure diffusion profiles. The Arrhenius relationship for diffusion, normal to (210) at 850 to 1150C under buffered conditions was,

D(m2/s) = 6.93 x 10-6exp[-384(kJ/mol)/RT]

For diffusion in air at 1000 to 1200C for the same orientation, the Arrhenius relationship was,

D(m2/s) = 1.70 x 10-8exp[-350(kJ/mol)/RT]

For diffusion under IW-buffered conditions and for experiments run in air, the diffusivities normal to (001) were similar to those for diffusion normal to (210).

D.J.Cherniak, Y.Liang: Geochimica et Cosmochimica Acta, 2007, 71[5], 1324-40