汶川地震断裂带科学钻探项目WFSD-2孔钻井液工艺研究

Research on Drilling Fluid Technology for WFSD-2 Hole of Wenchuan Earthquake Fault Scientific Drilling Project

摘要:

汶川地震断裂带科学钻探项目二号孔（WFSD-2），地质条件极为复杂，孔壁稳定性差。施工期间由于地层中水敏性矿物吸水膨胀、地层破碎及地应力释放等原因，多次发生孔壁缩径、坍塌掉块及漏失现象。针对以上问题，施工中采用了以低粘增效粉和改性沥青为主要原料的LBM-GLA钻井液体系，通过对钻井液配方、性能参数的合理调整与维护以及固相等方面的控制与处理，较好地解决了上述问题。重点介绍了WFSD-2孔各孔段钻井液的使用及维护情况。

Abstract:

The geological conditions were extremely complicated with poor wall stability in WFSD-2 hole drilling construction of Wenchuan earthquake fault scientific drilling project. Due to the water-sensitive formation of mineral water swelling, broken strata and stress release, the hole wall necking, collapsing and leakage happened many times. Through the adjustment and maintenance of the formulation, parameters, and solid control, LBM-GLA drilling fluid system with a low viscosity synergy powder and modified asphalt as the main raw materials was adopted in the construction; the above problems were successfully solved. This article mainly describes the use and maintenance of drilling fluid in each section of WFSD-2 hole.