9614229 McMillan This research proposes to develop and calibrate a new method of volatile analysis based on infrared reflectance spectroscopy, which will only require singly polished samples, and which does not rely on measurement of sample thickness for concentration determination. Preliminary results show that the technique will work for CO3 and H2O species in the concentration range above ~0.1-0.5 wt% for basaltic compositions, and encouraging results have been obtained for CO2 dissolved in rhyolite at the 500-2000 ppm level. These fundamental spectroscopic studies will be applied to several suites of samples. The results will be useful to workers in the fields of geochemistry and volcanology.