Oxygen

Stable Isotopes - Oxygen - 18O/16O

Abundance
16O = 99.762 % atom
17O = 0.038 % atom (not usually measured)
18O = 0.200 % atom

Gas analysed
CO2 (can be analysed as CO and O2 but not at this facility).

Standard Used
VPDB (Vienna Pee Dee Belemnite) and VSMOW for waters (Vienna Standard Mean Ocean Water, absolute isotope ratio (2005.20 ± 0.45) x 10-6 [Baeertschi,1976])

Equipment
Europa Geo 20-20 dual inlet for CO2 gas samples
GVI Isoprime coupled with AquaPrep for water and carbonate samples.
GVI Isoprime coupled with Hakatec high temperature analyser.
Laser fluorination line for silicates.

    Precision‰ Preferred sample size Minimum sample size Price
SOLIDS
18O & 13C carbonates 0.3 & 0.1 2mg as CaCO3 0.5mg  
18O silicates 0.1 5mg 2mg  
18O sulfate minerals 0.3 50mg 20mg  
18O & 34S sulfate minerals 0.2 & 0.3 50mg as BaSO4 20mg as BaSO4  
LIQUIDS
18O water 0.1 5-20 ml 0.5 ml  
18O & D water 0.1 & 1.0 5-20 ml 0.5 ml  
18O sulfate solution 0.3 20 mg as SO4 20 mg as BaSO4  
18O & 34S sulfate solution 0.2 & 0.3 50mg as BaSO4 20mg as BaSO4  
GAS
18O & 13C CO2 0.3 & 0.1 5ml STP* 1ml STP*  
*Standard Temperature and Pressure