Methods and compositions for modified well fluids. One method including combining an amount of a synthetic functionalized additive with an intermediate well fluid composition to form a synthetic functionalized additive-containing well fluid composition; the synthetic functionalized additive comprising a synthetic layered magnesium silicate that is covalently bonded to a functional group, and the intermediate well fluid composition comprising a water-based continuous phase with solid particles, wherein the synthetic functionalized additive increases suspension stability of the solid particles versus a well fluid composition comprising the solid particles without the synthetic functionalized additive.

Methods and compositions including treatment fluids that include geopolymers for use in subterranean formations are provided. The methods of the present disclosure include introducing a treatment fluid including a geopolymer material into a wellbore penetrating at least a portion of a subterranean formation, wherein the geopolymer material includes an aluminosilicate source, a metal silicate source, an activator, and water; contacting a first fluid present in the wellbore with the treatment fluid; and allowing the treatment fluid to displace at least a portion of the first fluid from at least a portion of the wellbore.

The invention relates to the field of drilling fluid, in particular to a saturated salt water drilling fluid of salt response type intelligent polymer and preparation method thereof. The drilling fluid contains two or more of the following components stored in admixture or separately: bentonite, NaOH, KCl, calcium carbonate, barite, NaCl, supramolecular fluid loss additive, supramolecular shear-enhancing agent, plugging agent, coating agent and water. The drilling fluid provided by the invention has the characteristics of salt response and self-assembly, can keep rheological properties such as rapid recovery of the sheared structure, low extreme high shear rate viscosity, good shear dilution property and the like in a high-salt environment, has good fluid loss reduction performance, reservoir protection performance and debris dispersion inhibition performance, and has good temperature resistance and pollution resistance performance.

The present disclosure relates to downhole fluid additives including a clay, a hydroxylated polymer, a cation, and water. The disclosure further relates to downhole fluids, including drilling fluids, spaces, cements, and proppant delivery fluids containing such as downhole fluid additive and methods of using such fluids. The downhole fluid additive may have any of a variety of functions in the downhole fluid and may confer any of a variety of properties upon it, such as salt tolerance or desired viscosities even at high downhole temperatures.

Methods and systems are provided for clay detection, clay typing, and clay volume quantification using downhole electromagnetic measurements conducted by a downhole logging tool on a formation at a low frequency less than 5000 Hz. The downhole electromagnetic measurements are used to determine permittivity data that characterizes permittivity of the formation at the low frequency less than 5000 Hz. The downhole low frequency electromagnetic measurements are nondestructive, and the results indicate it is with high sensitivity to the existence of clays.

A drilling fluid formulation is provided, which includes an aqueous base fluid, a synthetic modified phyllosilicate as an anti-sagging additive, an inorganic base, and a weighting agent (e.g. barite). The synthetic modified phyllosilicate contains a clay material (e.g. smectite) and a metal selected from ruthenium, rhodium, palladium, osmium, iridium, and platinum. The synthetic modified phyllosilicate is effective in preventing barite sagging as demonstrated by low sag factor when drilling at elevated temperatures. Rheology properties of the drilling fluid including gel strength, yield point, plastic viscosity, and storage modulus are also specified.

A method of treating a well that includes introducing a well treatment fluid into the well, and a well treatment fluid, are provided. The well treatment fluid comprises an aqueous base fluid, a bridging agent, a viscosifying agent, and a water soluble, biodegradable graft copolymer. In one embodiment, for example, the method is a method of cementing a casing in a well. In this embodiment, the well treatment fluid is a cement spacer fluid.

A drilling fluid formulation is provided, which includes an aqueous base fluid, a synthetic modified phyllosilicate as an anti-sagging additive, an inorganic base, and a weighting agent (e.g. barite). The synthetic modified phyllosilicate contains a clay material (e.g. smectite) and a metal selected from ruthenium, rhodium, palladium, osmium, iridium, and platinum. The synthetic modified phyllosilicate is effective in preventing barite sagging as demonstrated by low sag factor when drilling at elevated temperatures. Rheology properties of the drilling fluid including gel strength, yield point, plastic viscosity, and storage modulus are also specified.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger which is potassium permanganate. The drilling fluid composition includes an invert emulsion which includes a continuous phase including mineral oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

Described herein are methods of enhancing the rheological properties of a colloidal mineral suspension in a liquid with high-intensity acoustical energy. In some examples, the colloidal mineral suspension may be dehydrated after treatment with high-intensity acoustical energy.