The size and shape of the ice cuttings influence the choice of drilling regimes, as well as the design of drilling heads, augers, chip chambers, and internal drilling channels. To collect ice chips, two boreholes, VK-22 (30 m) and VK-23 (40 m), were drilled at Vostok station. Sieving was used to analyze the particle size distribution of the ice cuttings at full depth in both boreholes. The shape of the ice particles was examined microscopically at drilling depths of 5, 10, 15, 20, 25, 30, and 35 m of VK-23. The density of the snow-firm layer and the bulk density of ice cuttings were measured. The ice cuttings became finer-grained as the borehole depth increased. The prevailing fraction changes from 1.6-3 mm to 0.4-0.63 mm, the average particle diameter reduces from 1.55 mm to 0.06 mm, and the D10, D50, and D90 values decrease more than twice. The shape analysis revealed that the ice chips are dominated by equant and elongated particles, with medium shape projections described by parameters FF = 0.74 and ER = 0.67. A visual comparison of microscopic images shows that the thickness of the ice cuttings decreases as the depth of the well increases.
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