【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。更多还原

【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.更多还原