Plugging wellbores

摘要

A process for plugging a porous area of well bore which comprises pumping a shear thickening composition into the well under conditions of low shear to the portion of the well bore desired to be plugged at which point subjected to high shear to form a paste which plugs or seals the porous area. The shear thickening composition comprises a water-in-oil emulsion having granular bentonite dispersed in the oily phase, said oily phase having both an oil soluble amine and a polyamine derivative surfactant dissolved therein. The aqueous phase will preferably comprises a polyacrylamide solution. This process may be used for plugging wells having depths in excess of 8,000 feet.