Metamictization in zircon: Raman investigation following a Rietveld approach. Part II: Sampling depth implication and experimental data

Abstract

Profile line deconvolution following a Rietveld approach is applied to Raman spectra obtained from natural zircon grains from the European Alps. The corrected bandwidths are in perfect agreement with the values obtained from an established correction method (after Irmer) as far as the area of validity of the latter is concerned. For Raman active modes smaller than that, the Rietveld approach also yields accurate values for the true Raman bandwidth. Moreover, changes to instrument parameters are compensated by the correction routine. As for the studied zircon grains, Raman spectroscopy was shown to be a suitable tool for the examination of zoning (i.e. regions which show a variable degree of radiation-induced damage because of a different amount of incorporated uranium and/or thorium). This is complicated by the fact that the measured Raman signal is not restricted to the depth expected from the axial resolution (several micrometers) but a significant contribution comes from a comparatively large excitation volume (tens of micrometer deep). This sampling volume, however, lies within the same order of magnitude as zoning, which itself is blurred by the range of amorphization-causing alpha-particles.

Iron Doped-ZrSiO4: Structural, Microstructural and Vibrational Characterization

“…This value falls within the range of the reported values by Presser & Glotzbach 45 and Gucsik et al 46 .…”

“…The laser beam was focused on the sample with an acquisition time of 10 sec. Profile line deconvolution was performed following the approach as described by Presser & Glotzbach 45 . For the undoped sample we determined the true Raman bandwidth to be 3.3 ± 0.1 cm…”

Thermal history of the central Gotthard and Aar massifs, European Alps: Evidence for steady state, long‐term exhumation

“…The annealing kinetics of zircon fission tracks are, among other factors, a function of radiation damage [ Garver and Kamp , 2002; Garver et al , 2005; Rahn et al , 2004]. The degree of radiation damage of individual zircon crystals on a microscale can be characterized by Raman spectroscopy [e.g., Nasdala et al , 2001; Presser and Glotzbach , 2009].…”

Metamictization in zircon. Part I: Raman investigation following a Rietveld approach: Profile line deconvolution technique.

“…As will be shown in part two of this two-part study, the fast and reliable way of determining FWHM-values following a Rietveld approach can successfully be adapted to the quantitative description of metamictization in natural zircon. [18] …”