Crystal-plastic deformation of zircon: A defect in the assumption of chemical robustness

Abstract

Research Article| April 01, 2006 Crystal-plastic deformation of zircon: A defect in the assumption of chemical robustness Steven M. Reddy; Steven M. Reddy 1Tectonics Special Research Centre, Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845, Australia Search for other works by this author on: GSW Google Scholar Nicholas E. Timms; Nicholas E. Timms 1Tectonics Special Research Centre, Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845, Australia Search for other works by this author on: GSW Google Scholar Patrick Trimby; Patrick Trimby 2HKL Technology A/S, Majsmarken 1, 9500 Hobro, Denmark Search for other works by this author on: GSW Google Scholar Peter D. Kinny; Peter D. Kinny 3Tectonics Special Research Centre, Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845, Australia Search for other works by this author on: GSW Google Scholar Craig Buchan; Craig Buchan 3Tectonics Special Research Centre, Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845, Australia Search for other works by this author on: GSW Google Scholar Kevin Blake Kevin Blake 4Advanced Analytical Centre, James Cook University, Townsville, Queensland 4811, Australia Search for other works by this author on: GSW Google Scholar Geology (2006) 34 (4): 257–260. https://doi.org/10.1130/G22110.1 Article history received: 29 Jul 2005 rev-recd: 31 Oct 2005 accepted: 14 Dec 2005 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Steven M. Reddy, Nicholas E. Timms, Patrick Trimby, Peter D. Kinny, Craig Buchan, Kevin Blake; Crystal-plastic deformation of zircon: A defect in the assumption of chemical robustness. Geology 2006;; 34 (4): 257–260. doi: https://doi.org/10.1130/G22110.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Orientation contrast imaging and quantitative electron backscatter diffraction analysis of a zircon collected from an Indian Ocean gabbro reveal intragrain crystallographic misorientations (up to 14°) and low-angle orientation boundaries concentrated in the zircon tips. These features represent the formation and migration of dislocations and provide the first evidence of crystal-plastic deformation of zircon under crustal conditions. Panchromatic and wavelength cathodoluminescence (CL), combined with quantitative rare earth element (REE) ion microprobe analyses, demonstrate modification of zircon REE chemistry within the areas of crystal plasticity. These data indicate that the enhanced diffusion of REEs into the zircon is spatially linked to the presence of dislocations that behave as high-diffusivity pathways, increasing bulk diffusion rates and effective diffusion distances in the zircon by several orders of magnitude. In addition, discrete ∼2 μm zones of reduced panchromatic CL correspond exactly to the position of low-angle orientation boundaries and demonstrate a defect dependence on CL signal at high dislocation densities. The presence of deformation-related crystal-plastic microstructures in zircon, and their role in modifying elemental diffusion, questions the commonly made assumption of chemical robustness and has fundamental implications for the interpretation of zircon trace-element and isotopic data. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.