The geochemistry of Antarctic snow, Vostok Station

Thin layers of snow (as thin as a fraction of a millimetre) were taken and analysed for sodium in a flame photometer. When thin layers of snow are analysed for sodium an annual pattern is found with differences seen between summer and winter. From such studies it is possible to determine annual accumulation and annual evaporation and hence total precipitation. The same studies were carried out on the ice cores taken from the then 950m hole at Vostok. The accumulation rate was measured down the whole length of the ice core (to 950m). This was particularly interesting because if one can measure the accumulation rate then the date of various sections of the core can be made and thus the 950m core was dated.