Strengthening permeable undergound formations Siliceous materials in a permeable underground formation are strengthened by injecting an aqs soln. of an alkaline earth metal hydroxide into a borehole which passes through this formation. The soln. is used in sufficient amount and under sufficient pressure to press into the permeable formation a considerably greater volume of soln. that the amount which would penetrate into the formation under the pressure of the column of liquid in the borehole. The aqs. soln. is allowed to remain at rest in the permeable formation for a sufficient time and under a sufficiently high temperature to form the siliceous material into a permeable strengthened mass.
展开▼
