Vertical shaft construction method for promoting fracture dislocation and improving self-supporting capacity

Abstract

The invention discloses a vertical shaft construction method for promoting fracture dislocation and improving the self-supporting capacity. The vertical shaft construction method is suitable for being used during fracturing and permeability increasing of an oil and gas well. The vertical shaft construction method comprises the steps that firstly, reservoir parameters are detected, and rock mechanical parameters and ground stress parameters of a target mining interval of a reservoir are obtained; a vertical shaft is constructed, and the axial direction of the vertical shaft is perpendicular to the plane where the maximum and minimum horizontal principal stress directions are located; perforation and fracture forming are carried out, energy-gathered perforation and fracture forming are carried out through a perforating gun, and an included angle is formed between the perforation direction and the maximum horizontal principal stress direction; crack expanding and fracturing are carried out, specifically, the perforation cracks are subjected to crack expanding and fracturing through hydraulic fracturing, so that the perforation cracks communicate with one another to form a flat crack face; and crack dislocation self-supporting is carried out, specifically, a high-energy gas burning explosion technology is used for promoting crack shearing dislocation slippage, and a three-dimensional self-supporting crack network is constructed. By selecting the perforation fracture forming direction and utilizing the effect of a reservoir protolith stress field, the fracture surface generates dislocation and slippage to the maximum extent, and therefore the self-supporting effect is achieved.

Description

technical field [0001] The invention relates to a vertical shaft construction method, in particular to a vertical shaft construction method for promoting fracture dislocation and improving self-supporting ability, which is suitable for oil and gas wells for fracturing and increasing permeability. Background technique [0002] The exploration and development of unconventional gas reservoirs such as coalbed methane reservoirs, tight sandstone gas reservoirs, and shale gas reservoirs has become a hot spot. Unconventional oil and gas reservoirs have the characteristics of deep burial, high closure pressure, and low permeability. In order to fully tap the potential of the reservoir, establishing an interconnected fracture network is the key. However, artificially generated fractures may reclose under the closing pressure. For this reason, scholars at home and abroad have studied the theory of self-supporting fracturing stimulation. Self-supporting fracturing does not use or use ...

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Problems solved by technology

However, this direction often produces tensile failures, which are inconsistent with the sliding cracks required for self-supporting, and cannot produce sufficient slippage, which is not conducive to the self-supporting of hydraulic fractures after the fracturing measures are removed.

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