Articles | Volume 5, issue 2
Solid Earth, 5, 1319–1327, 2014

Special issue: Deformation mechanisms and ductile strain localization in...

Solid Earth, 5, 1319–1327, 2014

Research article 16 Dec 2014

Research article | 16 Dec 2014

Microscale strain partitioning? Differential quartz crystallographic fabric development in Phyllite, Hindu Kush, Northwestern Pakistan

K. P. Larson1, J. L. Lamming1,2, and S. Faisal1 K. P. Larson et al.
  • 1Earth and Environmental Sciences, University of British Columbia, Okanagan, 3247 University Way, Kelowna, BC V1V 1V7, Canada
  • 2Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, SK S7N 5E2, Canada

Abstract. Spatially referenced quartz c axis fabrics demonstrate the preservation of multiple, distinct fabrics in a specimen collected from northwestern Pakistan. The overall fabric yielded by the specimen is dominated by a single population of quartz grains, while the fabric signatures of two other unique, spatially distinct populations are overwhelmed. It is these minor fabrics, however, that provide information on temperature of deformation (403 ± 50 °C), differential stress (8.6 + 2.6/−1.5 MPa to 15.0 +3.8/−2.5 MPa), strain rate (10−16 s−1 to 10−15 s−1), and strain partitioning recorded by the specimen.

Short summary
This study demonstrates the importance of spatial resolution and registration in specimens analysed for crystallographic fabric analyses. In the specimen examined, the bulk crystallographic orientation was dominated by one fabric. Yet it was two secondary, spatially distinct fabrics that yielded potentially important information on deformation temperature, paleopiezometry, and strain rate.