Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Yamamoto, J. Articles by Kagi, H. Search for Related Content GeoRef GeoRef Citation

Application of densimetry using micro-Raman spectroscopy for CO₂ fluid inclusions: a probe for elastic strengths of mantle minerals

¹ Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
² Institute for Geothermal Sciences, Graduate School of Science, Kyoto University, Beppu 874-0903, Japan
³ Geochemical Laboratory, Graduate School of Science, The University of Tokyo, Hongo, Tokyo 113-0033, Japan

^* Corresponding author, e-mail: jyamamoto{at}whoi.edu

Micro-Raman spectroscopy enables precise non-destructive analyses of CO₂ density in a very small volume. By applying this method to CO₂ fluid inclusions in minerals, a contrast is apparent in the CO₂ density specific to mineral species in a mantle-derived spinel lherzolite xenolith entrained by ascending magma. The rock investigated in this study comprises four mineral species: olivine, orthopyroxene (opx), clinopyroxene (cpx), and chromianspinel (spinel). The CO₂ densities in the fluid inclusions in these minerals are 1.006–1.035, 1.148–1.154, 1.150–1.154 and 1.189–1.194 g/cm³, respectively. During transport of the rock by magma and subsequent cooling, the CO₂ fluid inclusions change their volume due to both elastic and plastic properties of the host mineral, which are sensitive to differential pressure between internal pressure of the CO₂ fluid inclusion, and stress in surrounding crystal lattice. We tested the possibility that the volume of CO₂ fluid inclusion changes by the differential pressure. Existing models dealing with the volume change of fluid inclusion in response to deformation of host mineral do not explain the density gradation, particularly that between pyroxenes and spinel. We propose that combination of precise determination of fluid density in mantle-derived minerals and observation of microstructure in the host mineral provides a deep insight into the deformation mechanism of natural minerals under high differential pressure and temperature.

Key-words: micro-Raman spectroscopy, fluid inclusion, CO₂, mantle xenolith, elastic deformation.

This article has been cited by other articles:

				A. Ladenberger, P. Lazor, and M. Michalik CO2 fluid inclusions in mantle xenoliths from Lower Silesia (SW Poland): formation conditions and decompression history European Journal of Mineralogy, August 1, 2009; 21(4): 751 - 761. [Abstract] [Full Text] [PDF]