Substantiation of reliability of operational sampling on mine fields of Verkhnekamskoe salt deposit

Operational exploration sampling on the Verkhnekamskoe salt deposit routinely comprises the channel sampling and core sampling in the underground boreholes. In the beginning stage of deposit development, it was assumed that channel and core tests are equivalent. Comparison study has shown that a difference of the insoluble residue content in samples taken with different techniques is statistically significant. The results of study showed that the core tests are not representative, because of selective core abrasion during drilling. Reliability of the channel sampling was confirmed experimentally. In the article, the comparison test results of channel samples of 6x3 cm and 3x2 cm of size are presented. Statistical analysis of chemical composition data obtained at samples of different size showed their equivalence. It allowed confirming that the channel sampling method is more reliable in the condition of Verkhnekamskoe salt deposit.