Silicon diffusion was measured in anorthitic feldspar under dry low-pressure (0.1MPa) conditions using a 30Si tracer. The sources of diffusant consisted of microcrystalline 30Si-doped synthetic feldspar of composition comparable to the feldspar specimens. Distributions of 30Si were measured using Rutherford back-scattering spectrometry and nuclear reaction analysis, using the reaction, 30Si(p,γ)31P. The Arrhenius relationship, obtained for anneals at 1atm in air, was:

D(m2/s) = 3.79 x 10-7 exp[-465(kJ/mol)/RT]

D.J.Cherniak: Earth and Planetary Science Letters, 2003, 214[3-4], 655-68