The pressure and temperature dependences of Si volume diffusion rates were determined in a single crystal of Pyp75Alm15Gr10 garnet at 6 to 25GPa and 1400 to 1800C by using the 29Si tracer diffusion method. Diffusion profiles were obtained using secondary ion mass spectrometry in the depth-profiling mode. The Si diffusion in garnet was expressed by:

D(m2/s) 7.9 x 10-8exp[-345.6(kJ/mol)/RT]

A.Shimojuku, T.Kubo, T.Kato, T.Yoshino, M.Nishi, T.Nakamura, R.Okazaki, Y.Kakazu: Physics of the Earth and Planetary Interiors, 2014, 226, 28-38