The present invention provides methods of fracturing high temperature subterranean zones and viscous aqueous foamed fracturing fluids therefor. A fracturing fluid of this invention comprises water, a terpolymer of 2-acrylamido-2-methylpropane-sulfonic acid, acrylamide and acrylic acid or salts thereof, a gas, a foaming agent and a viscosity breaker for effecting a controlled reduction in the viscosity of the fracturing fluid.

The present invention provides compositions and methods for enhancing subterranean well productivity by enhancing fracture conductivity. A method of increasing the conductivity of a fracture in a portion of a subterranean formation comprising providing a slurry comprising a fracturing fluid, a degradable material, and proppant particulates coated with a tackifying agent; allowing the degradable material to become at least temporarily attached to the tackifying agent coated onto the proppant part...

An increase in effective propped lengths is evidenced in hydraulic fracturing treatments by the use of ultra lightweight (ULW) proppants. The ULW proppants have a density less than or equal to 2.45 g/cc and may be used as a mixture in a first proppant stage wherein at least one of the proppants is a ULW proppant. Alternatively, sequential proppant stages may be introduced into the formation wherein at least one of the proppant stages contain a ULW proppant and where at least one of the following...

A system and a method for heterogeneous proppant placement in a fracture (12) in a subterranean formation (18) are disclosed. The system includes a delivery system (10) for delivering proppant and treatment fluid to the fracture (12), a sensor (20) for measuring geometry of the fracture and a computer (24) in communication with the sensor (20). The computer (24) includes a software tool for real-time design of a model (38) for heterogeneous proppant placement in the fracture (12) based on data f...

A method of propping at least one fracture in a subterranean formation is provided, the method comprising: forming a plurality of fly ash aggregates, each fly ash aggregate comprising an aqueous component and fly ash; introducing the plurality of fly ash aggregates into the at least one fracture; and curing at least a portion of the fly ash aggregates into at least one hardened mass. Also provided are methods of fracturing a subterranean formation and methods for the downhole formation of proppa...

A method of increasing productivity and recovery of wells in oil and gas fields includes determining a direction of maximal horizontal stresses, producing at least two wells so that they are spaced from one another in a direction corresponding to the direction of the maximum horizontal stresses, forming in at least one of the wells at least one vertical slot oriented substantially from the at least one well to the other of the wells, and introducing a hydrofracturing fluid at least into the at l...

Methods are presented to induce a screenout during a subterranean formation fracturing or combined fracturing and gravel packing treatment having a viscoelastic surfactant-based carrier fluid by laying down a filter cake at least a portion of which is a base-soluble material, injecting proppant slurry, and causing hydrolysis and dissolution of the solid base-soluble material by adding base so that leak-off increases, the concentration of proppant in the fracture increases, and the proppant scree...

The present invention discloses two stage subterranean zone fracturing fluids and methods. A two stage subterranean zone fracturing fluid of the invention comprises a first stage fluid comprising a foamed liquid containing a water soluble gel breaker and a second stage fluid that comprises a viscous liquid containing a metal cross-linked gelling agent. Another two stage subterranean zone fracturing fluid comprises a first stage fluid comprising a foamed liquid containing a water soluble gel brea...

The present invention involves enhancing the conductivity of subterranean propped fractures penetrating formations while controlling proppant flowback. More particularly, the present invention relates to improved consolidation performance of resin-coated proppants and their use in controlling proppant flowback. Some embodiments of the present invention provide methods of controlling proppant flowback from a fracture in a subterranean zone comprising the steps of providing resin coated proppant; ...

Method for hydraulic fracturing of wells by transporting a cross-linked polymer containing a proppant down a wellbore in a carrier fluid, allowing the cross-linked polymer to coalesce into a polymer phase and squeezing the cross-linked polymer as a fracturing fluid is provided. Composition of the cross-linked polymer solution and the selection of additives may be varied to adjust the viscosity, degradation time and other properties of the fracturing fluid.