寨上金矿复杂地层深孔岩心钻探技术

Deep hole core drilling technology in complex formation of Zhaishang gold deposit

ZK4816孔是首个在岷县寨上金矿区实施的千米以深钻孔。针对矿区复杂地层钻进难、护壁难等问题,通过实施深孔岩心钻探工程,同步开展了钻探技术研究与实践,成功应用了广谱冲洗液、加大口径钻具、定向钻进等技术措施,钻进深度达到1172.88 m。广谱冲洗液与植物胶冲洗液相比护壁周期提高了3倍,采用加大口径钻具钻进可形成大环状间隙,大幅提升冲洗液携带粗颗粒岩粉的能力,“广谱冲洗液+加大口径钻具”技术的应用有效保证了深孔施工。为下一步复杂地层深孔岩心钻探工作提供了参考依据。

ZK4816 borehole is the first drilling with a depth of 1000 meters implemented in Zhaishang gold deposit area,Min County.For the problems of difficult drilling,wall protection etc.in complex formation of mining area,through the implementation of deep core drilling project,drilling technology research and practice were carried out simultaneously,and technical measures such as GSP drilling fluid,enlarged diameter drilling tools and directional drilling were successfully applied.The drilling depth reached 1172.88m.The wall protection period of GSP drilling fluid was three times longer than that of natural plant gum drilling fluid.Drilling with enlarged diameter drilling tools can form a large annular gap and greatly improve the ability of drilling fluid to carry coarse rock powder.The application of“GSP drilling fluid&enlarged diameter drilling tools”technology effectively ensures the deep hole construction.This paper provides a reference for the next deep core drilling work in complex strata.