Compositional zoning in garnet and kinetics of metamorphic crystallization |
| |
Authors: | Yu. L. Gulbin |
| |
Affiliation: | 1. St. Petersburg State Mining University, 21-aya liniya 2, St. Petersburg, 199106, St. Petersburg, Russia
|
| |
Abstract: | The kinetics of zoned garnet porphyroblast growth is exemplified in a sample of garnet-staurolite-biotite schist from the northern Ladoga region. The diffusion-controlled porphyroblast growth was accompanied by a decrease in the kinetic coefficient during phase reactions. Even at insignificant (1–2°C) thermal overstepping, the leading role of diffusion as a factor that controls kinetics of porphyroblast growth in medium-grade metapelites is consistent with the parameters of metamorphic crystallization: T = 500–650°C, t = 1 Ma; D A1 app = 10?14 cm2/s, L = 0.2–0.6 cm, r = 1–3 mm, ΔC Al = 1.5 × 10?4–1.5 × 10?3 mol/cm3. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|