四川尔呷地吉铅锌矿区复杂地层钻探施工技术

Drilling technology for complex formation in the Ergadiji lead-zinc mine area in Sichuan

摘要:

四川尔呷地吉铅锌矿区位于南北向甘洛-小江断裂（本区内称为马拉哈断裂）北段与马拉哈背斜的复合部位。区域地质条件复杂，岩层破碎、裂隙发育，存在钻孔坍塌、漏失、缩径、掉块等钻探难题。为避免井内复杂事故、缩减钻井周期、降低作业风险，在该矿区开展了钻探技术研究工作。以ZK4522、ZK4737、ZK7545钻孔施工问题为例，重点剖析了钻孔事故频发的原因，提出了改进措施，总结了适合该矿区钻探施工的钻孔结构设计，并对不同地层使用冲洗液配方进行了阐述，对水泥浆护壁工艺、套管护壁工艺采取了技术管控措施，在该矿区取得了良好的效果，形成了一套具有实际参考价值的钻探施工方案，为该矿区以后的施工提供了技术保障措施和经验，同时对其他类似钻探施工也具有一定的借鉴意义。

Abstract:

The Erxiadiji lead-zinc mining area in Sichuan is located at the combination of the northern segment of the north-south Ganluo-Xiaojiang fault （called the Malaha fault in this area） and the Malaha anticline. The regional geological conditions are complex， with broken rock formations and developed fissures， and there are drilling problems such as borehole collapse， leakage， diameter reduction， and falling stones. In order to avoid downhole incidents， shorten the drilling period and reduce operation risks， research work on drilling technology has been carried out in the mining area. Taking drilling problems in ZK4522， ZK4737， ZK7545 holes as examples， the causes for frequent drilling incidents are analyzed， improvement measures are put forward， and the drilling structure design suitable for the mining area is summarized. The formulation of flushing fluid used for different strata is expounded， and technical control measures are proposed for cement slurry wall protection and casing wall protection with good results achieved in the mining area. A set of drilling plans have been developed with practical reference value， which provides technical support measures and experience for future drilling in the mining area， and also some reference for other similar drilling works.