Static elasticity of cordierite II

Author(s)
Katharina Sarah Scheidl, Giacomo Diego Gatta, Thomas Pippinger, Beatrice Schuster, Christina Trautmann, Ronald Miletich-Pawliczek
Abstract

Two natural CO

2-rich cordierite samples (1.00 wt% CO

2, 0.38 wt% H

2O, and 1.65 wt% CO

2, 0.15 wt% H

2O, respectively) were investigated by means of Raman spectroscopy and single-crystal X-ray diffraction at ambient and high pressures. The effect of heavy-ion irradiation (Au 2.2 GeV, fluence of 1 × 10

12 ions cm

-2) on the crystal structure was investigated to characterize the structural alterations complementary to results reported on hydrous cordierite. The linear CO

2 molecules sustained irradiation-induced breakdown with small CO

2-to-CO conversion rates in contrast to the distinct loss of channel H

2O. The maximum CO

2 depletion rate corresponds to ~12 ± 5 % (i.e. ~0.87 and ~1.49 wt% CO

2 according to the two samples, respectively). The elastic properties of CO

2-rich cordierite reveal stiffening due to the CO

2 molecules (non-irradiated: isothermal bulk modulus K

0 = 120.3 ± 3.7 GPa, irradiated: K

0 = 109.7 ± 3.7 GPa), but show the equivalent effect of hydrous cordierite to get softer when irradiated. The degree of anisotropy of axial compressibilities and the anomalous elastic softening at increasing pressure agrees with those reported for hydrous cordierite. Nevertheless, the experimental high-pressure measurements using ethanol-methanol reveal a small hysteresis between compression and decompression, together with the noticeable effect of pressure-induced over-hydration at pressures between 4 and 5 GPa.

Organisation(s)
Department of Mineralogy and Crystallography
External organisation(s)
Technische Universität Darmstadt, GSI Helmholtzzentrum für Schwerionenforschung, Areva GmbH, Università degli Studi di Milano-Bicocca
Journal
Physics and Chemistry of Minerals
Volume
41
Pages
617-631
No. of pages
15
ISSN
0342-1791
DOI
https://doi.org/10.1007/s00269-014-0675-z
Publication date
04-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
105116 Mineralogy, 105113 Crystallography
Keywords
ASJC Scopus subject areas
Geochemistry and Petrology, General Materials Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/c5ad75c3-c3ed-42ce-959f-1c06d0aa6475