松科1井是全球第1口陆相白垩纪科学探井,由主井(又称北井)和南井组成,主井164.77~1792m井段连续取心。分析了主井取心钻进存在的钻井液技术难点;经过室内钻井液体系优选,根据不同地层分别采用了PAM钻井液体系、DFD-LG—CMC钻井液体系和DFD-NH4HPAN—SAKH钻井液体系;同时结合钻井液粘度的合理控制技术、降低循环压降的钻井液技术等,先后解决了松散砂层、水敏性泥岩和硬脆性泥岩中的取心钻进技术难题,探索出了一条用低成本钻井液进行类似科学钻探工程的成功之路。
SLCORE-I well is the first Cretaceous continental scientific drilling well in the world. It's the most important engineering method of acquiring deep earth sciences research samples for "Major Geological Events in the Earth Surface System during the Cretaceous and Greenhouse Climate Change" project (2006CB701400), which belongs to the National Basic Research Program (also called 973 Program). It is made up of main well (also called north well) and south well. The continuous coring section of the main well is from 164.77 to 1792 m. The author analyzes the drilling fluid technical difficulties of the main well and processes lab optimization test of drilling fluid systems. To overcome the difficulties in the core drilling process of loose sandstone, water sensitive mudstone and friable hard mudstone, not only different drilling fluid systems such as PAM drilling fluid, DFD-LG-CMC drilling fluid and DFD-NH4HPAN-SAKH drilling fluid, but also feasible controlling technology of viscosity and drilling fluid technology of decreasing circulating pressure loss are used, which explores one successful way of using low cost drilling fluid to proceed similar scientific drilling project.