The current method comprises producing a loss control blend by selecting blend ingredients that contribute to thixotropy of the blend, density of the blend, and compressive strength of the set blend, wherein at least one of the blend ingredients contributes positively to all three of these attributes.

Excessive water production from oil reservoirs is a main challenge facing the oil and gas industry nowadays. Polymeric gelants have been widely applied to seal the water production zones leading to a more feasible production operation. This disclosure introduces a new inorganic crosslinker that can potentially replace the conventional chromium acetate as crosslinkers for polyacrylamide in low-temperature reservoirs. The developed formulation has the advantage of being more environment-friendly compared to the known-to-be toxic chromium acetate. The formulation has been tested through the whole pH range examining the rheological behavior of the mature gels in the temperature range between 25 to 100° C. While chromium acetate was proven to be sensitive to the presence of sour gases, namely CO.sub.2 and H.sub.2S, due to the inability to produce a stable gel at the acidic conditions, the proposed crosslinkers are more tolerable towards the high acidity. Unlike the conventional crosslinkers, the gelation rate in the proposed system was found to decrease with the increase in pH. The system has a controllable gelation time at pH conditions between 3.5 and 8.5 and is the most stable in the temperature range between 25 to 100° C.

Methods for drilling a wellbore into a subterranean formation include preparing a drilling fluid and circulating the drilling fluid in the wellbore while drilling in the subterranean formation, forming a filtercake from the drilling fluid, creating or encountering one or more fractures in the subterranean formation while drilling, and allowing a portion of the filtercake formed to at least partially seal the one or more fractures while continuing the drilling.

A method of servicing a wellbore in a formation comprising circulating in the wellbore a wellbore servicing fluid wherein an equivalent circulating density of the wellbore servicing fluid is from about 1% to about 15% greater than a fracture pressure of the formation, and introducing to the wellbore a balloon-inhibiting tunable spacer (BITS) fluid wherein at least about 1 wt. % of the BITS fluid is retained by the formation.

Lost circulation material (LCM) compositions for sealing lost circulation zones in wellbores may include an epoxy resin, a curing agent, an amide accelerator, and calcium carbonate having an average particle size of from 1,000 microns to 10,000 micron. The epoxy resin includes at least one of 2,3-epoxypropyl-o-tolyl ether, C12-C14 alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether, butyl glycidyl ether, or cyclohexanedimethanol diglycidyl ether. The epoxy resin can also include bisphenol-A-epichlorohydrin epoxy resin. Methods of treating a lost circulation zone of a wellbore include injecting the LCM compositions into the lost circulation zone and curing the LCM compositions, where the LCM compositions include an epoxy resin, a curing agent, an amide accelerator, and calcium carbonate having an average particle size of from 1,000 microns to 10,000 microns.

Disclosed are a temporary plugging agent and a preparation method thereof, and a method for temporary plugging and fracturing of a high-temperature reservoir. The temporary plugging agent includes the following components in mass fractions: acrylamide 5%, composite crosslinking agent 1%, laponite 1%, ammonium persulfate 0.1% and water 92.9%.

Bentonite-based grout fluids and methods of using the grout fluids are provided. A method of using a grout fluid includes placing a geothermal conduit in at least one hole in the earth, providing a grout fluid consisting essentially of water and a bentonite-based grout, wherein the bentonite-based grout consists essentially of calcium carbonate, a bentonite, one or more grout-setting modifiers, and one or more thermally conductive materials, introducing the grout fluid into a space between the geothermal conduit and sidewalls of the at least one hole so that the grout fluid is in contact with the geothermal conduit, and after introducing the grout fluid, allowing the grout fluid to set to fix the geothermal conduit to the at least one hole, wherein after setting, the grout fluid has a hydraulic conductivity of between about 1×10.sup.−7 cm/s and about 1×10.sup.−9 cm/s.

Solid shale inhibitor additives and methods of using such additives to, for example, inhibit shale are provided. In some embodiments, such methods include providing an aqueous treatment fluid that includes an aqueous base fluid and a solid shale inhibitor additive, the solid shale inhibitor additive including carrier particles and a treatment composition that includes a shale inhibitor; and introducing the treatment fluid into a wellbore penetrating at least a portion of a subterranean formation.

A method of servicing a wellbore in a formation comprising circulating in the wellbore a wellbore servicing fluid wherein an equivalent circulating density of the wellbore servicing fluid is from about 1% to about 15% greater than a fracture pressure of the formation, and introducing to the wellbore a balloon-inhibiting tunable spacer (BITS) fluid wherein at least about 1 wt. % of the BITS fluid is retained by the formation.

A method of reducing water saturation onto surfaces exposed to hydrocarbons during the production of hydrocarbons from subterranean formations by altering the wettability of the surface of the formation with surface modified nanoparticles.