Helium diffusion in zircon: Effects of anisotropy and radiation damage revealed by laser depth profiling
作者: Alyssa J. AndersonMatthijs C. van SoestKip V. HodgesJohn M. Hanchar
作者单位: 1School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA
2Earth Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
刊名: Geochimica et Cosmochimica Acta, 2020, Vol.274 , pp.45-62
来源数据库: Elsevier Journal
DOI: 10.1016/j.gca.2020.01.049
关键词: ZirconHelium diffusionAnisotropyRadiation damageThermochronology
英文摘要: Abstract(#br)Laser depth profiling of laboratory-induced helium diffusion profiles in natural zircon confirms that helium diffusivity is crystallographically controlled and significantly anisotropic. Experiments on Mud Tank zircon with low degrees of alpha radiation damage (5.6 × 10 16 to 1.3 × 10 17 α/g) indicate that c ‖ diffusion is ∼400 to 700 times faster than a ‖ diffusion over the experimental temperature range investigated (400–600 °C). This magnitude of diffusive anisotropy implies that zircon crystals with different crystal morphologies record different helium closure temperatures. Zircon diffusion models commonly used in thermal-kinematic modeling programs do not properly account for diffusive anisotropy, and consequently, are likely to over- or underestimate helium closure...
全文获取路径: Elsevier  (合作)
影响因子:3.884 (2012)

  • zircon 锆石
  • depth 
  • diffusion 扩散
  • damage 损伤
  • laser 激光
  • radiation 辐射
  • anisotropy 蛤异性
  • profiling 仿形切削