caa a22 4500 467890242 CHVBK 20180406152747.0 cr unu---uuuuu 170328e20060101xx s 000 0 eng 10.1007/s00710-005-0104-6 doi (NATIONALLICENCE)springer-10.1007/s00710-005-0104-6 Alpha particle haloes in chlorite and cordierite [Elektronische Daten] [L. Nasdala, M. Wildner, R. Wirth, N. Groschopf, D. C. Pal, A. Möller] Summary: Effects of the impact of natural long-term irradiation with alpha particles in one chamosite and one cordierite sample were characterised in detail using electron microprobe, Raman microprobe, optical absorption spectroscopy (cordierite only), and transmission electron microscopy (TEM; cordierite only) analysis. In both cases, the impact of 4He cores (alpha particles) that were emitted from actinide-bearing mineral inclusions has caused the formation of radiation damage haloes in the host mineral. These haloes have maximum radii of about 33 µm (chamosite) and 47 µm (cordierite). They show notably changed optical properties, i.e., intensified absorption of light as recognised by brown (chamosite) and yellow (cordierite) pleochroism and enhanced or even anomalous interference colours. In spite of the significant disturbance of their short range order, alpha particle haloes are characterised by generally low degrees of structural radiation damage. This is indicated by rather moderate broadening of vibrational bands and, in the case of cordierite, apparently undisturbed electron diffraction patterns in the TEM. Intensive damage, virtually close to an amorphous state, was only found in cordierite up to a few tens of nanometres away from actinide-bearing inclusions. This damage is mainly assigned to recoils of heavy nuclei upon emission of an alpha particle, which have particle trajectory lengths that are three orders of magnitude shorter than those of the alpha particles. Similar to observations on biotite, alpha particle haloes in chamosite and cordierite as observed in the optical microscope may be considered as representative of a very early stage of the metamictisation process. Springer-Verlag/Wien, 2006 Nasdala L. Institut für Geowissenschaften - Mineralogie, Johannes Gutenberg-Universität, Mainz, Federal Republic of Germany aut Wildner M. Institut für Mineralogie und Kristallographie, Universität Wien, Vienna, Austria aut Wirth R. GeoForschungsZentrum, Potsdam, Federal Republic of Germany aut Groschopf N. Institut für Geowissenschaften - Mineralogie, Johannes Gutenberg-Universität, Mainz, Federal Republic of Germany aut Pal D. C. Department of Geological Sciences, Jadavpur University, Kolkata, India aut Möller A. Institut für Geowissenschaften, Universität Potsdam, Federal Republic of Germany aut Mineralogy and Petrology Springer-Verlag 86/1-2(2006-01-01), 1-27 0930-0708 86:1-2<1 2006 86 710 https://doi.org/10.1007/s00710-005-0104-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00710-005-0104-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nasdala L. Institut für Geowissenschaften - Mineralogie, Johannes Gutenberg-Universität, Mainz, Federal Republic of Germany aut NATIONALLICENCE 700 1- Wildner M. Institut für Mineralogie und Kristallographie, Universität Wien, Vienna, Austria aut NATIONALLICENCE 700 1- Wirth R. GeoForschungsZentrum, Potsdam, Federal Republic of Germany aut NATIONALLICENCE 700 1- Groschopf N. Institut für Geowissenschaften - Mineralogie, Johannes Gutenberg-Universität, Mainz, Federal Republic of Germany aut NATIONALLICENCE 700 1- Pal D. C. Department of Geological Sciences, Jadavpur University, Kolkata, India aut NATIONALLICENCE 700 1- Möller A. Institut für Geowissenschaften, Universität Potsdam, Federal Republic of Germany aut NATIONALLICENCE 773 0- Mineralogy and Petrology Springer-Verlag 86/1-2(2006-01-01), 1-27 0930-0708 86:1-2<1 2006 86 710 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer