Oil-gas reservoir fracturing construction method

Abstract

The invention belongs to the field of oil exploitation and particularly provides an oil-gas reservoir fracturing construction method. The oil-gas reservoir fracturing construction method comprises a prepad fluid stage and a main sand adding stage. According to the prepad fluid stage, fracturing liquid is injected at multiple levels of construction displacement which is increased level by level from the lowest construction displacement to the highest construction displacement; and according to the main sand adding stage, sand-carried liquid is injected at the highest construction displacement,wherein the lowest construction displacement is 45-65 % of the highest construction displacement. In the preferably-selected implementation mode, design is conducted according to different construction sections, the different fracturing liquid displacement and corresponding fracturing liquid viscosities and using quantities are adopted, the mode of different-particle-diameter variable density sandadding is adopted, by utilizing the setting effect of a supporting agent, the net pressure in cracks at the supporting agent non-setting position is increased, thus the seam making height and the supporting height of remote well cracks are increased, the flow guiding capacity of the cracks at remote wells is improved, and the progressively-decreasing speed of the single-well capacity is decreased.

Description

Technical field [0001] The invention belongs to the technical field of petroleum exploitation, and specifically relates to a fracturing construction method for oil and gas reservoirs that can increase the support height of fractures in remote wells. Background technique [0002] In the current fracturing technology, the support efficiency at the fracture height near the well is relatively high, while the support efficiency for the far well fracture is relatively low. First of all, due to the sedimentation effect of proppant, the farther the well zone is, the greater the horizontal migration distance of the proppant, the greater the vertical settlement height, and the proppant will basically settle in the fracture when it reaches the end of the fracture. Bottom; and the near-wellbore zone is continuously injected with new proppant, so the vertical support efficiency is relatively high. Secondly, the fracture height is also high near the well and low at the far well. When the cra...

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Problems solved by technology

[0003] The above reasons will greatly reduce the fracture creation height and support height of far-well fractures, greatly reducing the fracture stimulation volume and fracturing stimulation effect

However, the current fracturing technology generally adopts constant fracturing fluid type and viscosity, constant displacement, and the same type of proppant and proppant density, which cannot effectively reduce the adverse effects caused by the above reasons in a targeted manner.

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