A multi-slug staged method for plugging a fractured formation includes: determining an average opening of fractures around a well as D, an average particle size of bridging particles for first-stage plugging as D.sub.1 that is slightly less than D, and average particle sizes of plugging particles for second to last-stage plugging as D.sub.2-D.sub.n, where D.sub.n is small enough to form a tight plugging layer; and sequentially injecting a plugging slurry only containing the bridging particles having the average particle size of D.sub.1, plugging slurries containing the plugging particles having the average particle sizes of D.sub.2-D.sub.n-1, and a plugging slurry containing the plugging particles having the average particle size of D.sub.n into the fractures to achieve the fractured formation plugging.

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 method of hydraulic fracturing may comprise mixing at least one liquid sand mixture with a fluid to produce a fracturing fluid; and conveying the fracturing fluid to two or more wellbores simultaneously, wherein the wellbores penetrate a subterranean formation.

A method of drilling is disclosed that includes introducing a water-based drilling fluid into a drill string disposed within a wellbore, circulating the water-based drilling fluid through the drill string and the wellbore, and extending the wellbore using the drill string while circulating the water-based drilling fluid, wherein the water-based drilling fluid includes water and a lubricating additive including a de-oiled cake, wherein the de-oiled cake are residues obtained after extraction of oil from a plant source, wherein the de-oiled cake is in particulate form having a particle size of 100 microns or less. A composition is disclosed that includes water-based drilling fluid including water and a lubricant additive comprising a de-oiled cake, wherein the de-oiled cake are residues obtained after extraction of oil from a plant source and wherein the de-oiled cake has a particle size of 100 microns or less.

Provided are methods, compositions, and systems embodying cement compositions and the synergistic effect of lost circulation materials (LCMs) and fluid loss control additives (FLCAs) thereupon for cementing subterranean zones. A method of subterranean well cementing, comprising providing a cement composition comprising a hydraulic cement, a first FLCA, a LCM, and water, wherein the first FLCA comprises a water-soluble polymer with repeating units comprising a 5- to 6-membered cyclic amide; introducing the cement composition into a wellbore penetrating a subterranean formation, wherein inclusion of the first FLCA and the LCM in the cement composition fluid reduces fluid loss into the subterranean formation, wherein the subterranean formation has fractures with a width of from about 1 micron to about 800 microns, and wherein the subterranean formation has a permeability of about 1 millidarcy to about 300 Darcy; and allowing the cement composition to set in the subterranean formation.

A method of hydraulic fracturing may comprise mixing at least one liquid sand mixture with a fluid to produce a fracturing fluid; and conveying the fracturing fluid to two or more wellbores simultaneously, wherein the wellbores penetrate a subterranean formation.

A method of hydraulic fracturing may comprise mixing at least one liquid sand mixture with a fluid to produce a fracturing fluid; and conveying the fracturing fluid to two or more wellbores simultaneously, wherein the wellbores penetrate a subterranean formation.

A composition is for making a drilling fluid a non-invasive drilling fluid. The composition has a first component comprising particles having a scratch hardness above 2 Mohs and a second component comprising particles selected from the group of fragmented seeds of Tamarindus indica, comminuted bark from Litsea glutinosa, or comminuted Ocimum tenuiflorum. Also disclosed is a non-invasive drilling fluid having the composition, and a method for drilling a wellbore.

The present disclosure provides methods, compositions, and systems embodying cement compositions and the synergistic effect of lost circulation materials (LCMs) and fluid loss control additives (FLCAs) thereupon for cementing subterranean zones. A method of subterranean well cementing, comprising providing a cement composition comprising a hydraulic cement, a first FLCA, an LCM, and water, wherein the first FLCA comprises a water-soluble polymer with repeating units comprising a 5- to 6-membered cyclic amide; introducing the cement composition into a wellbore penetrating a subterranean formation, wherein inclusion of the first FLCA and the LCM in the cement composition fluid reduces fluid loss into the subterranean formation, wherein the subterranean formation has fractures with a width of from about 1 micron to about 800 microns, and wherein the subterranean formation has a permeability of about 1 milliDarcy to about 300 Darcy; and allowing the cement composition to set in the subterranean formation.

Energy created by a propellant can form a fracture in a subterranean formation. For example, a treatment fluid can be introduced into a subterranean formation. A propellant can be positioned in the subterranean formation. The propellant can be detonated to generate a fracture in the subterranean formation for receiving at least part of the treatment fluid. The treatment fluid may include an acid, a hydrolysable in-situ acid generator, a chelating agent, a hydrolysable in-situ chelating agent generator, or mixtures thereof.