Development method of deep shale gas

Abstract

The invention discloses a development method of deep shale gas. The method comprises the following steps: (1) evaluating the gas content of shale gas, and establishing and analyzing the relationship between the gas content and the natural gas occurrence state; (2) drilling three horizontal wells away from a water layer and a fault zone; (3) firstly, mechanically segmenting the three horizontal wells, completing in-segment perforation, and then penetrating a shaft at the perforation position through acid liquor; (4) conducting large-scale fracturing through the horizontal section; (5) injecting fluid in sequence of medium-viscosity slick water, low-viscosity acid liquid and medium-viscosity glue liquid, and after the proppant is conveyed in place, exciting the high-energy material to generate a violent oxidation-reduction reaction in a mode of transmitting current to the stratum; and (6) obtaining oil fuel substances after high-pressure mixed gas exploited by the vertical well section gas recovery well and the horizontal well section gas recovery well is purified and separated, and further conducting deep processing according to product requirements. The application of the method makes economic and effective development of deep shale gas possible, is an important breakthrough in the technical field of shale gas methods, and has important significance in improving the development technical level and economic benefits of unconventional oil and gas reservoirs.

Description

technical field [0001] The invention relates to the field of oil and gas reservoir development, in particular to a deep shale gas development method. Background technique [0002] At present, with the deepening of shale gas exploration and development, the probability of occurrence of deep complex shale gas is increasing. The so-called "complex shale gas" refers to shale gas reservoirs with a carbonate rock content of more than 20% in lithology and a large number of horizontal bedding fractures, texture fractures and high-angle natural fractures (filled or unfilled) structurally , its complexity can easily lead to out-of-control fracture height of fracturing fractures, and then the net pressure of main fractures is greatly reduced, and it is difficult to achieve the goal of volume fracturing. substantially restricted. In terms of three-dimensional stress characteristics, due to the extrusion of tectonic stress, the minimum horizontal principal stress may be close to the ve...

AI Technical Summary

Problems solved by technology

Simply reducing the concentration of the thickener will reduce the drag-reducing effect of deep shale gas fracturing, and the drag-reducing effect is a crucial parameter, which cannot be lowered easily, otherwise, the injection displacement of fracturing construction will be greatly reduced , complex cracks cannot be realized

But instead of emulsion-type slick water, the application of the two kinds of slick water in the field, the corresponding injection equipment and supporting procedures are quite different, and there are problems in the operability of the field implementation, which will also cause deep shale gas fracturing. Bringing risks and uncertainties to construction

More importantly, the viscosity of emulsion-type slick water is also as high as 2-3 mPas, which may still be too high for deep shale gas fracturing, making it difficult to further communicate and extend more small micro-scale fracture systems

Therefore, neither the powder type nor the emulsion type slick water is suitable for deep shale gas well fracturing

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