Gellable treatment fluids with clay-based gel retarders and related methods

A system comprising:

• a pump fluidly coupled to a tubular that penetrates a subterranean formation,
• wherein the tubular contains a gellable treatment fluid that comprises
• an aqueous base fluid;
• a base polymer;
• a polymeric organic crosslinking agent comprising a crosslinkable polymer;
• and
• a clay-based gel retarder comprising a plurality of clay platelets, wherein the platelets have at least one surface that has been treated with a surface activity modifier that comprises one selected from the group consisting of sodium silicate, an alkaline lignosulfate, an amino alkylene phosphonate, propylene carbonate, and any combination thereof;
• wherein the clay-based gel retarder comprises at least one selected from the group consisting of a laponite, a modified laponite, and combination thereof, wherein the clay-based gel retarder is used in aggregate, not pre-hydrated, form and wherein the base polymer comprises a copolymer of acrylamide and t-butyl acrylate and the crosslinkable polymer is polyethyleneimine.

A method comprising:

• providing a gellable treatment fluid comprising:
• an aqueous base fluid;
• a base polymer;
• a polymeric organic crosslinking agent comprising a crosslinkable polymer;
• and
• a clay-based gel retarder that comprises a plurality of clay platelets having an average diameter of about 10 nm to about 100 nm and an average thickness of about 0.5 nm to about 2 nm and, wherein the platelets have at least one surface that has been treated with a surface activity modifier that comprises one selected from the group consisting of sodium silicate, an alkaline lignosulfate, an amino alkylene phosphonate, propylene carbonate, and any combination thereof;
• wherein the clay-based gel retarder comprises at least one selected from the group consisting of a laponite, a modified laponite, and combination thereof, wherein the clay-based gel retarder is used in aggregate, not pre-hydrated, form and wherein the base polymer comprises a copolymer of acrylamide and t-butyl acrylate and the crosslinkable polymer is polyethyleneimine;
• introducing the gellable treatment fluid into a wellbore penetrating a subterranean formation, the subterranean formation comprising a porous matrix;
• infiltrating at least a portion of the porous matrix of the subterranean formation with the gellable treatment fluid;
• and
• forming a gel in the porous matrix of the subterranean formation with the gellable treatment fluid.

A method comprising:

• providing a gellable treatment fluid by concurrently combining an aqueous base fluid, a base polymer, a polymeric organic crosslinking agent comprising a crosslinkable polymer, and a dry form of a clay-based gel retarder,
• wherein the clay-based gel retarder comprises (1) at least one selected from the group consisting of a laponite, a modified laponite, a natural hectorite, a montmorillonite, a sapiolite, and any combination thereof and (2) a plurality of clay platelets, wherein the platelets have at least one surface that has been treated with a surface activity modifier that comprises one selected from the group consisting of sodium silicate, an alkaline lignosulfate, an amino alkylene phosphonate, propylene carbonate, and any combination thereof;
• wherein the clay-based gel retarder comprises at least one selected from the group consisting of a laponite, a modified laponite, and combination thereof, wherein the clay-based gel retarder is used in aggregate, not pre-hydrated, form and wherein the base polymer comprises a copolymer of acrylamide and t-butyl acrylate and the crosslinkable polymer is polyethyleneimine;
• introducing the gellable treatment fluid into a wellbore penetrating a subterranean formation;
• and
• forming a gel with the gellable treatment fluid in at least a portion of the wellbore, at least a portion of the subterranean formation, or both.