Determination of H2O and CO2 concentrations in fluid inclusions in minerals using laser decrepitation and capacitance manometer analysis.

摘要: Water and carbon dioxide concentrations within individual selected groups of fluid inclusions in quartz were analyzed by using laser decrepitation quantitative capacitance manometer determination. The useful limit detection (calculated as ten times the typical background level) is about 5 x 10(-10) mol H2O 10(-11) CO2; this content translates into an aqueous inclusion approximately 25 micrometers diameter. CO2/H2O determinations for 38 samples (100 separate measurements) have a range amounts 5.119 10(-9) to 1.261 10(-7) mol; CO2 7.216 1.488 10(-8) mol, mole ratios 0.011 1.241. Replicate ratio three identical (?) clusters average 0.0305 +/- 0.0041 1 sigma. Our method offers much promise analysis inclusions, sensitive, selective when energy not so great melt mineral (laser pits 50 diameter), permits rapid (approximately h per sample analysis).