大深度强高岭土化断层泥断裂带地层钻井技术研究OA

The 104ZK07 borehole of Zhaoxian-Daguanzhuang project is located at Jincheng Town of Laizhou City in Shandong province.During construction,it encountered a deep-seated fault zone stratum with strongly kaolinized fault gouge.Affected by the release of formation stress,water-sensitive collapse and hole shrinkage occurred in multiple sections of borehole.Moreover,the development of vertical joints further aggravated the collapse,leading to a series of downhole accidents such as a sudden rise in pump pressure,drill pipe sticking due to falling rock fragments,difficulty in adding drilling pipes during round trips,and obstruction in fishing core barrel.To address these problems,the project team optimized the drilling fluid system by sequentially adopting non-solid-phase drilling fluid,low-solid-phase drilling fluid,and finally replacing it with film-forming anti-sloughing non-solid-phase drilling fluid.The innovative application of powder-fishing pipe drilling tool optimized the annular clearance and enhanced sand removal capacity.Combined with the synchronous operation process of wireline coring and powder-fishing pipe,the complex section was successfully drilling.Application resuls showed that this scheme significantly improves borehole wall stability,reduces tool wear and downhole accident rate,the borehole reaches a final depth of 1868.50 m,successfully completing drilling task,which proves a reliable technical reference for the construction of similar deep-hole complex formations.