SLAP , hydrogen isotopes

Oxygen-isotopic ratios were determined by the CO2 equilibrium method of Epstein and Mayeda (1953). The hydrogen-isotopic ratios of water were determined by the method of Friedman and Woodcock (1957). The data are reported in the usual delta notation with SMOW as the standard (Craig, 1961). Our analyses of I.A.E.A. SLAP was —424.6%o 5D and —55.95%o... 

Hydrogen isotopes are measured in parts per thousand reladve to the SMOW standard and are calculated in an analogous manner to that for oxygen isotopes (see Eqn [7.1]) and expressed as 5D /oo. Precision is between 1 and 2 / . 6D values for the SLAP standard reladve to SMOW are -428 /m. D/H ratios are usually measured on H2 gas which is produced from the reduction of water at high temperatures. 

FIGURE 15.2 Potential variation in the hydrogen isotopic composition of a range of different materials. Reprinted from T.B. Coplen et al. [16], with permission from Coplen. SLAP, Standard Light Antarctic Precipitation GISP, Greenland Ice Sheet Precipitation VSMOW, Vienna Standard Mean Ocean Water NBS, National Bureau of Standards NGS, natural gas standards. 

Figure 6 Natural variations in hydrogen isotope abundances. V-SMOW, SLAP, and GISP are international reference water samples available from the International Atomic Energy Agency (IAEA) in Vienna, Austria.

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