Russian developments of equipment and technology of deep hole drilling in ice

This paper presents information about deep hole drilling in ice at Russian station Vostok. Borehole design and technical characteristics of downhole and surface borehole equipment are provided. On the basis of extensive data obtained in the process of 5G deep well drilling at station Vostok, processes running on the bottom of the hole, such as breaking-cutting of ice, bottom hole cleaning and carrying of drill cuttings out of the hole, cuttings collection in the filter are discussed. The factors having the greatest influence on ice drilling efficiency are considered. The process of penetrating to the subglacial lake Vostok is described in Conclusions and preliminary analysis of deep drilling results, ice sheet, ice core, drilling characteristics, the borehole are provided.