Jump to ContentJump to Main Navigation
Show Summary Details
More options …

American Mineralogist

Journal of Earth and Planetary Materials

Ed. by Baker, Don / Xu, Hongwu


IMPACT FACTOR 2018: 2.631

CiteScore 2018: 2.55

SCImago Journal Rank (SJR) 2018: 1.355
Source Normalized Impact per Paper (SNIP) 2018: 1.103

Online
ISSN
1945-3027
See all formats and pricing
More options …
Volume 97, Issue 4

Issues

TOF-SIMS and electron microprobe investigations of zoned magmatic orthopyroxenes: First results of trace and minor element analysis with implications for diffusion modeling

Kate Saunders / Stefan Rinnen
  • Physikalisches Institut, Westfälische Wilhelms Universität Münster, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Jon Blundy
  • Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, U.K.
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Ralf Dohmen
  • Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, U.K.
  • Institut für Geologie, Mineralogie und Geophysik, Ruhr-Universtät Bochum, 44780 Bochum, Germany
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Stephan Klemme
  • Institut für Mineralogie, Westfälische Wilhelms Universität Münster, Corrensstrasse 24, 48149 Münster, Germany
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Heinrich F. Arlinghaus
  • Physikalisches Institut, Westfälische Wilhelms Universität Münster, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
Published Online: 2015-04-02 | DOI: https://doi.org/10.2138/am.2012.3893

Abstract

Zoned phenocrysts in volcanic rocks potentially provide an archive of magmatic processes. As a crystal grows and comes into contact with different melt batches, the chemical and textural signature of this journey is recorded within its crystal lattice. The timescale of some magmatic processes can be investigated through the relaxation of chemical gradients across crystal growth zones through the application of diffusion modeling techniques. One of the current limitations to diffusion modeling is the spatial and analytical resolution of the chemical profile that conventional techniques such as electron probe microanalyzer (EPMA), dynamic secondary ion mass spectrometry (SIMS), and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) can achieve. Here, for the first time, we present time-of-flight (TOF) SIMS (TOF-SIMS) data for zoning of orthopyroxene crystals from the May 1982 eruption of Mount St. Helens volcano, U.S.A., and cross-calibrate these data between backscattered electron images and EPMA. TOF-SIMS has the advantage of being able to achieve micrometer to nanoscale spatial resolution of major elements as well as analyses of light elements, such as Li, and trace and minor elements (Na, K, and Ni) at concentrations that cannot be achieved by EPMA, provided that convolution (overlap) effects and polyatomic mass inferences are carefully considered. With TOF-SIMS analyses we identified zoning of Li on a spatial scale (ca. 5-10 μm) that would be inaccessible to most other conventional analytical techniques. Preliminary results indicate that Li, a fast-diffusing element, may be introduced to the crystals in the minutes, hours, or days prior to eruption and may provide insights into pre-eruptive magmatic processes. Thus, TOF-SIMS has the potential to be a powerful tool for obtaining minor and trace element profiles across compositional interfaces within crystals at high-spatial resolution.

Keywords: TOF-SIMS; diffusion; orthopyroxene; Li

About the article

Received: 2011-05-23

Accepted: 2011-12-06

Published Online: 2015-04-02

Published in Print: 2012-04-01


Citation Information: American Mineralogist, Volume 97, Issue 4, Pages 532–542, ISSN (Online) 1945-3027, ISSN (Print) 0003-004X, DOI: https://doi.org/10.2138/am.2012.3893.

Export Citation

© 2015 by Walter de Gruyter Berlin/Boston.Get Permission

Comments (0)

Please log in or register to comment.
Log in