Abstract:Drilling in complicated stratum is always the most difficult technical problem in the mineral resources exploration as well as the project reconnaissance and construction. This article analyzes the method of hole wail protection and leaking stoppage for drilling in complicated stratum; and with the case of drilling project of glauber salt mine in the foot of Liupanshan Mountain in Ningxia, proposes to use cement-sodium silicate-cloth sack in great crack in Karst Stratum. The nature of the dropout channel and the analysis method of leaking position, the principle of hole wail protection and leaking stoppage, and the correct method to determine grouting pressure and maximum grouting amount are elaborated. This method has been proved extremely effective with good economic efficiency.