Controlled sublimation, in a low-vacuum scanning electron microscope, was used to reveal features of the triple junctions of accretion ice from the Antarctic ice sheet. Energy dispersive X-ray micro-analysis data showed that the features were comprised mainly Mg, S and O; although small amounts of Na and Ca were also sometimes observed. Synchrotron X-ray topography showed that the ice grains contained dislocation densities ranging from about 107 to more than 1010/m2.

Observation of Sulfate Crystallites in Vostok Accretion Ice. D.Cullen, I.Baker: Materials Characterization, 2002, 48[4], 263-9