Abstract: The positions of hydraulic fractures may be detected during multistage reservoir stimulation operations. Fracturing fluid is injected into a well at a pressure above the fracturing pressure to produce at least one hydraulic fracture. Then, a marker slug is injected into the well. Next, additional fracturing fluid is injected into the well. When the marker slug enters at least one of the hydraulic fractures, a detectable pressure response is observed, and the position of a hydraulic fracture may be detected from the volume of fracturing fluid injected after injection of the marker slug. The marker slug is a fluid that has a viscosity and/or density that is different from the fracturing fluids injected before and after the marker slug. This technique may be combined with other well operations, such as plugging at least one hydraulic fracture or creating at least one new hydraulic fracture.

Abstract: A method of stimulating the inflow of oil and/or gas from the wellbore, in particular, a hydraulic fracturing method, is disclosed. The method of hydraulic fracturing comprises the stages: injecting a slug of a proppant-free fluid through the well into a formation for hydraulic fracture creation and propagation; injecting a slug of proppant-laden slurry into the formation to create a proppant pack in the hydraulic fracture; injecting a slug of slurry that contains a fluid and the polyelectrolyte complex-based proppant aggregates to create permeable channels in the near-wellbore area of the hydraulic fracture; injecting a slug of a displacement fluid into the well. This sequence of operations allows avoiding the proppant slurry overdisplacement deep into the hydraulic fracture, maintaining high fracture conductivity, and increasing the well productivity.

Abstract: A method is provided for detecting hydraulic fractures positions during multistage reservoir stimulation. Fracturing fluid is injected into a well at a pressure above the fracturing pressure to produce at least one hydraulic fracture. After this, a marker slug is injected into the well. Further, the fracturing fluid is re-injected into the well. When the marker slug enters at least one of the hydraulic fractures, a detectable pressure response is observed, and the position of a hydraulic fracture is detected from the volume of fracturing fluid injected after injection of the marker slug. The marker slug is a slug (portion) of fluid differing in the viscosity and/or density from the fracturing fluids injected before and after the marker slug. In other embodiments, the method for detecting a hydraulic fracture position is combined with other well operations, for example, with plugging of at least one hydraulic fracture or placement of at least one new hydraulic fracture.

Abstract: A method of stimulating the inflow of oil and/or gas from the wellbore, in particular, a hydraulic fracturing method, is disclosed. The method of hydraulic fracturing comprises the stages: injecting a slug of a proppant-free fluid through the well into a formation for hydraulic fracture creation and propagation; injecting a slug of proppant-laden slurry into the formation to create a proppant pack in the hydraulic fracture; injecting a slug of slurry that contains a fluid and the polyelectrolyte complex-based proppant aggregates to create permeable channels in the near-wellbore area of the hydraulic fracture; injecting a slug of a displacement fluid into the well. This sequence of operations allows avoiding the proppant slurry overdisplacement deep into the hydraulic fracture, maintaining high fracture conductivity, and increasing the well productivity.

Abstract: According to the claimed method, fracturing fluid is injected into a well containing a plurality of perforated intervals to create, and facilitate the propagation of, a hydraulic fracture in at least one of the perforated intervals; then, the suspension containing insoluble degradable material, oppositely charged polyelectrolytes and/or their precursors is injected into the well; at the same time, a degradable viscous phase, non-miscible with fracturing fluid, is formed from the oppositely charged polyelectrolytes and/or their precursors; a degradable plug is formed in at least one of the perforated intervals, fracture, or wellbore; diversion of the fracturing fluid flow to the next perforated interval is provided with subsequent plug degradation in at least one of the perforated intervals, fracture, or wellbore within the required time.

Abstract: A technique facilitates a well treatment, such as a well stimulation. The technique comprises injecting a gel containing proppant into a wellbore extending into a subterranean formation. Additionally, a low viscosity fluid is injected into the wellbore with the gel either simultaneously or separately. An additive or additives may be used to maintain the gel in the low viscosity fluid. The technique further comprises separating the gel into slugs and then causing the slugs to flow into fractures in the subterranean formation.

Abstract: A method and system for delivering materials downhole employing a shear thickening treatment fluid. The viscosity of the shear thickening treatment fluid increases with increasing shear rate. The shear thickening fluid may inhibit particulate dispersion, settling or a combination thereof at high shear rates and facilitate dispersion and/or settling of the particulates and/or formation of pillars or clusters in the fracture at low shear rates.