A gel breaking system comprising a source of hydrogen peroxide and an activator selected from the group consisting of triazine-based activators, phthalimide-based activators and mixtures thereof are provided. Also, described are methods of using the gel breaking system to break the gelled component of a treatment fluid used in a gravel packing operation for a well.

A gel composition for use in subterranean formations is disclosed. The composition can comprise a base fluid, a cross-linkable polymer that is soluble in the base fluid, a nonionic surfactant and a cross-linking agent. The gel composition has improved crosslinked stability. The gel composition can be injected into the subterranean formation as a fracturing fluid and allowed to penetrate the formation. Preferably, the gel composition effectively blocks the water-bearing regions while the oil or gas producing regions are left unblocked so that the oil or gas can be recovered.

Various embodiments disclosed related to compositions and methods of using the same for treating subterranean formations. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in a subterranean formation a composition that includes a viscosifier and that also includes a hydrophobically-modified polymer including at least one nitrogen-containing repeating unit.

Various embodiments disclosed relate to compositions including a viscosifier polymer and a polyamine viscosity modifier and methods of using the same for treatment of subterranean formations. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in a subterranean formation a composition including a viscosifier polymer and a polyamine viscosity modifier.

The provided method allows optimizing the fracturing design (frac design) while taking into account the two-dimensional modelling of the transport processes in the fracture. The generation of the fracturing design in a well comprises the steps of: obtaining data on hydraulic fracturing including the proppant pumping schedule and the fibre pumping schedule for various types of fibres; generating a degradation matrix for the various types of fibres; generating possible options of the hydraulic fracturing operation according to the fibre type and pumping schedule. Moreover, the method of hydraulic fracturing, which comprises generating a schedule of fracturing in a well, preparing a fracturing fluid containing carrier fluid, proppant, additives, and fibres, and pumping the fracturing fluid into the formation through the well following the selected (optimal) option of the fracturing operation, is provided.

Friction reducers, fracturing fluid compositions and methods for treating subterranean formations, wherein friction reducer is a reacted, grafted or blend of natural gum and polyacrylamide having a molecular weight between 300,000 and 30,000,000.

A friction reducer comprising a copolymer of acrylamide, an anionic monomer, a zwitterionic monomer or a cationic monomer, a physical ligand or a chemical ligand, wherein the acrylamide amounts to at least 50% (w/w) of the total monomer content. The friction reducer is useful in hydraulic fracturing operations and is obtained by controlled radical polymerization at a temperature between 30° C. and 70° C. using iodine as polymerization control agent.

This disclosure provides drilling fluids and additives as well as fracturing fluids and additives that contain cellulose nanofibers and/or cellulose nanocrystals. In some embodiments, hydrophobic nanocellulose is provided which can be incorporated into oil-based fluids and additives. These water-based or oil-based fluids and additives may further include lignosulfonates and other biomass-derived components. Also, these water-based or oil-based fluids and additives may further include enzymes. The drilling and fracturing fluids and additives described herein may be produced using the AVAP® process technology to produce a nanocellulose precursor, followed by low-energy refining to produce nanocellulose for incorporation into a variety of drilling and fracturing fluids and additives.

Methods include pumping a fracturing pad fluid into a subterranean formation under conditions of sufficient rate and pressure to create at least one fracture in the subterranean formation, the fracturing pad fluid including a carrier fluid and a plurality of bridging particles, the bridging particles forming a bridge in a fracture tip of a far field region of the formation. Methods further include forming a first plurality of fibers in situ into the subterranean formation to form a low permeability plug with the bridging particles, and pumping a proppant fluid comprising a plurality of proppant particles.

Well treatment fluids, and methods for treating wellbores or fracturing subterranean formations, which include acrylamide polymer or copolymer crosslinked with one or more crosslinkers and one or more iron-containing compounds are provided. The fluids and methods may be used to carry proppants into fractures and to increase fluid recovery in hydraulic fracturing applications