Sand control agent and process

A method for forming a consolidated gravel pack in a washed-out interval adjacent to a borehole in an unconsolidated or loosely consolidated formation comprising:

• a) perforating a cased borehole at an interval of the formation having a washed-out interval adjacent said borehole;
• b) placing sand into said washed-out interval via perforations in the borehole;
• c) injecting an aqueous solution of an alkali metal hydroxide, ammonium hydroxide, or organoammonium hydroxide into said interval through perforations contained in the borehole which solution is of a strength sufficient to react with a water-miscible organic solvent containing an alkylpolysilicate to form a permeability retentive cement sufficient to exclude formation fines or sand;
• d) injecting thereafter a spacer volume of a water-immiscible hydrocarbonaceous liquid into said interval;
• and
• e) injecting thereafter via the perforations a water-miscible organic solvent containing an alkylpolysilicate into said interval containing said sand in an amount sufficient to react with the aqueous hydroxide solution in step c) so as to form a permeability retentive silica cement which binds the sand sufficiently to exclude the fines or sand.