Hydroxide in olivine: A quantitative determination
of the absolute amount and calibration of the IR spectrum.

David. R. Bell1, George R. Rossman

Division of Geological and Planetary Sciences
California Institute of Technology
Pasadena, CA 91125, USA

Joachim Maldener2, Denis Endisch3, Friedel Rauch

Institut für Kernphysik
J.W. Goethe-Universität
August-Euler-Str 6,
D-60486, Frankfurt (M), Germany

1Current address: Department of Chemistry and Biochemistry, Arizona State University, Tempe AZ 85282, USA

2Current address: Meisenweg 18, 63454 Hanau, Germany

3Current address Allied Signal Inc., 1349 Moffet Park Drive, Sunnyvale, CA 94089, USA


Journal of Geochemical Research, 108(B2), 2105, doi:10.1029/2001JB000679, 2003.




Olivine is an important host of H in the Earth's upper mantle and the OH abundance in this mineral determines many important physical properties of the planet's interior. To date, natural and experimentally hydrated olivines have been analyzed by uncalibrated spectroscopic methods with large (± 100%) uncertainties in accuracy. We determined the H contents of three natural olivines by 15N nuclear reaction analysis (NRA) and use the results to calibrate the common IR spectroscopic method for quantitative H analysis of olivine. OH content (expressed as ppm H2O by weight) is 0.188 times the total integrated absorbance of the fundamental OH stretching bands in the region 3650 - 3100 cm-1. The results indicate that an upward revision of some previous determinations by factors of between 2 and 4 is necessary. The most hydrous naturally occurring mantle derived olivine analyzed to date contains 240 ppm wt. H2O, while the solubility of H in olivine at its high pressure limit of stability is approximately 6000 ppm wt. H2O. A posteriori application of this calibration to experimentally hydrated olivines may be limited due to the spectral differences from the calibration samples and use of non-polarized spectra.

Figure 5. Correlation between the NRA analysis and the infrared integrated intensity.

Illustration of the baseline problem

Comparison of NRA to the Paterson Method


Data Files

GRR 1012
alpha = E parallel b
beta = E parallel c
gamma = E parallel a

GRR 1695
E parallel alpha
E parallel beta
E parallel gamma

KLV 23

Bai p9016-1