Application of long-distance coring technology in horizontal holes for water hazard control effect verification in a mine in North China

Abstract:

To accurately assess the effectiveness of water hazard control in mine area， addressing the limitations of traditional vertical coring methods-such as limited coverage， high costs， prolonged drilling cycles， and sparse formation data， an innovative approach was adopted. This involved using long-distance coring in horizontal directional holes to perform coring operations in previously treated working faces. After analyzing the formation conditions and comparing SR， Sichuan series， and QXT-RBX series coring tools， during the drilling of inspection holes 4-18A and 4-25， the SQ-MWD directional equipment paired with a drilling tool assembly of ?152.4 mm coring bit + Sichuan-6-3 coring barrel + ?89 mm heavy-weight drill pipe + ?89 mm drill pipe + ?121 mm drill collar + top drive setup were selected to real-time control drilling parameters and perform coring. A total of 10 coring operations were conducted in the two verification holes， covering an exploration area of 0.48 km2. This method not only reduced costs but also significantly improved the drilling success rate， achieving a coring recovery rate of over 80%， with some sections reaching 100%. The cores were intact with excellent columnar integrity， effectively reflecting the water hazard control results and providing more accurate geological data for subsequent development.