Abstract
A granulite facies high strain zone was studied on Capricorn Ridge, part of the Mt. Hay block granulites in the Arunta inlier, central Australia. Deformation occurred in these primarily mafic composition granulites at lower crustal conditions (∼8 kb, ∼800 °C) at 1740–1690 Ma. Pervasive and consistently oriented foliation (striking SSW and dipping steeply) and lineations (pitching steeply eastward) occur within the shear zone. The high strain zone is recognized by the presence of SL-tectonites, parallelism of grain shape fabrics and lithologic boundaries, transposition of lithologic boundaries into parallelism with the foliation, and the local occurrence of sheath-like folds. Field-based fabric mapping uses compositional foliation intensity as a proxy for finite strain to document strain variations within the Capricorn Ridge high strain zone. There is no observed microstructural grain size reduction that corresponds to these strain variations. Fabric intensity increases from the centers of the major lithologic units towards the contacts. 100 m-scale strain localization within Capricorn ridge occurs adjacent to major lithologic contacts, indicating competency contrast during lower crustal deformation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
