Basal slip and mechanical anisotropy of biotite Academic Article uri icon

abstract

  • The basal slip systems of biotite and their mechanical expressions have been investigated by shortening single crystals oriented to maximize and minimize shear stresses on (001). Samples loaded at 45 to (001) exhibit gentle external rotations associated with dislocation glide. High-angle kink bands in these samples are limited to sample corners. Samples shortened perpendicular to (001) show no evidence of nonbasal slip and fail by fracture over all conditions tested. The mechanical response of biotite shortened at 45 to (001) is nearly perfectly elastic-plastic. The strength of biotite shortened perpendicular to (001) exceeds that measured parallel to (001) and is pressure dependent. Application of the results to deformation within the continental crust suggests that biotite oriented favorably for slip is much weaker than most other silicates over a wide range of geologic conditions. Its presence within foliated rocks and shear zones may limit locally the stresses that can be supported. -from Authors

published proceedings

  • Journal of Geophysical Research

author list (cited authors)

  • Kronenberg, A. K., Kirby, S. H., & Pinkston, J.

complete list of authors

  • Kronenberg, Andreas K||Kirby, Stephen H||Pinkston, John

publication date

  • January 1, 1990 11:11 AM