Many people use atmospheric O2 as a reference, which has d18O = +23.5 
per mil and d17O = +12.0 per mil (Kroopnick & Craig, 1972, Science, 
175: 54-55).  Can you calibrate your O2 reference gas this way?


>Hi all,
>I would like to assign a reasonably accurate d17O and d18O to an O2 
>reference gas we recently obtained. Any chance I can send ~100 mL of 
>this O2 to several interested labs? Please respond offline if you 
>are willing to help me with this effort. Thank you.
>Andrew Schauer
>Earth and Space Sciences
>University of Washington
>Seattle, WA 98195
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Simon Poulson
Research Professor
Dept. of Geological Sciences & Engineering MS-172
University of Nevada - Reno
1664 N. Virginia St.
Reno, NV 89557-0138. USA
(775) 784-1104
Fax: (775) 784-1833
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