Studies of experimentally deformed calcite have produced a remarkably complete data set that potentially apply to deforma- tion processes in marble mylonites. However, few data are avail- able from natural marble shear zones, thus limiting assessment of the importance of the laboratory data to natural systems. This project is an integrated microstructural study of a well preserved marble mylonite from the central metasedimentary Belt of the Ontario Grenville. The study of this shear zone provides a natural laboratory to examine processes in a variably deformed marble, ranging from protolith to ultra-mylonite. Results will provide field evidence to allow a comparison of experimentally and naturally produced textures as it applies to the extra- polation of experimentally-derived flow laws to geological conditions.
