Abstract:The fault gouge formation containing breccia was drilled in the south of Aikeng mining area of Qinghai Province, continuous drilling was almost impossible, because borehole collapsing, block falling and sticking often occurred. By the match usage of sodium silicate and related drilling fluid additives, sodium silicate potassium base inhibition flushing fluid was prepared to protect the hole wall by the formation pressure balance; and by increasing the outside diameters of diamond bit and reamer adjusting, borehole collapse, shrinkage, and sticking were solved.