Raman spectroscopy of laser-induced oxidation of titanomagnetites
Version of Record online: 19 JAN 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Journal of Raman Spectroscopy
Volume 42, Issue 6, pages 1413–1418, June 2011
How to Cite
Bauer, M., Davydovskaya, P., Janko, M., Kaliwoda, M., Petersen, N., Gilder, S. and Stark, R. W. (2011), Raman spectroscopy of laser-induced oxidation of titanomagnetites. J. Raman Spectrosc., 42: 1413–1418. doi: 10.1002/jrs.2849
- Issue online: 17 JUN 2011
- Version of Record online: 19 JAN 2011
- Manuscript Accepted: 21 OCT 2010
- Manuscript Received: 1 JUL 2010
- local heating;
- confocal Raman
Titanomagnetites are important carriers of magnetic remanence in nature and can track redox conditions in magma. The titanium concentration in magnetite bears heavily on its magnetic properties, such as saturation moment and Curie temperature. On land and in the deep ocean, however, these minerals are prone to alteration which can mask the primary magnetic signals they once recorded. Thus, it is essential to characterize the cation composition and oxidation state of titanomagnetites that record the paleomagnetic field. Raman spectroscopy provides a unique tool for both purposes. Nonetheless, the heat generated by the excitation laser can itself induce oxidation. We show that the laser power threshold to produce oxidation decreases with increasing titanium content. With confocal Raman spectroscopy and magnetic force microscopy (MFM) on natural and synthetic titanomagnetites, a non-destructive Raman imaging protocol was established. We applied this protocol to map out the composition and magnetization state within a single ex-solved titanomagnetite grain in a deep-sea basalt. Copyright © 2011 John Wiley & Sons, Ltd.