A method of forming a barrier to overcome lost circulation in a subterranean formation. The method includes injecting a polymer-sand nanocomposite into one or more lost circulation zones in the subterranean formation where the polymer-sand nanocomposite is formed from sand mixed with a polymer hydrogel. Further, the polymer hydrogel includes a hydrogel polymer, an organic cross-linker, and a salt. The sand additionally comprises a surface modification. The associated method of preparing a polymer-sand nanocomposite lost circulation material for utilization in forming the barrier is provided.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.

A method includes treating a reservoir with a damaged near wellbore region (NWR), including introducing a liquid foam treatment into a wellbore proximate to the damaged NWR, where the liquid foam treatment has a solution medium and nanobubbles, transmitting an acoustic wave towards the damaged NWR such that the nanobubbles collapse, causing fluid flow pathways to form for hydrocarbon production.

A system includes a solution generation tool for generating a liquid foam treatment, where the liquid foam treatment has a solution medium and nanobubbles, where the nanobubbles migrate along a concentration gradient, and an acoustic signal generator transmits an acoustic signal. The system also includes a downhole tool signally coupled to the acoustic signal generator fluidly coupled to the solution generation tool, and the downhole tool transmits an acoustic wave into an NWR and introduces the liquid foam treatment into the wellbore proximate to the NWR.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.

A system and method for water shutoff, including providing a treatment fluid including a polymer and a nitrogen-generating compound through a wellbore into a water zone in a subterranean formation, generating nitrogen gas in the water zone by a reaction of the nitrogen-generating compound, generating foam from the nitrogen gas and the treatment fluid in the water zone to give foamed polymer in the water zone, and sealing the water zone with the foamed polymer.

The present disclosure a leak-proof lost-circulation control water-based drilling fluid composition and preparation method and use thereof.

Methods and compositions for performing a sealing operation in a wellbore. An example method introduces a sealant composition into the wellbore while the sealant composition is under shear. The sealant composition comprises a thixotropic material, a conformance gel system, and an aqueous base fluid. The sealant composition is placed into a target location, and applied shear is reduced to the sealant composition when in the target location thereby allowing the sealant composition to thicken in the target location. Fluid flow across the target location is reduced by a fluid seal formed by the thickened sealant composition.

A preparation method of a fully adaptive modified nanographene plugging type anti-collapse drilling fluid is disclosed. A modified nanographene slurry anti-collapse agent and a water-based drilling fluid containing the modified nanographene slurry anti-collapse agent are disclosed. The preparation method includes subjecting a nanographene and a mixed acid to a first contact to obtain a mixed liquid, dropwise adding potassium chlorate into the mixed liquid under the condition of ice-bath pan to carry out a modification treatment, so as to obtain a modified nanographene, and subjecting the modified nanographene to a second contact with water to prepare a modified nanographene slurry.

Release of hydrochloric acid, hydrofluoric acid and fluoroboric acid into a well may be controlled by introducing into the well an aqueous fluid containing ammonium chloride, ammonium bifluoride, ammonium fluoroborate, ammonium tetrafluoroborate or a mixture thereof and a breaker. After being introduced into the well, the ammonium salt reacts with the breaker and the acid is released into the well.

A method for strengthening a subterranean formation is disclosed herein. A method of strengthening a subterranean formation includes: introducing a first fluid into the subterranean formation, wherein the first fluid includes polyvalent cations; and introducing a second fluid into the subterranean formation, wherein the second fluid includes a dissolved silicate in an aqueous-base fluid; wherein the dissolved silicate reacts with the polyvalent cations in the subterranean formation to form a reaction product including precipitated silicate in the subterranean formation.