A method for evaluating productivity contribution of multi-porous media by volume stimulation in unconventional reservoirs

Abstract

The invention discloses an evaluation method for unconventional reservoir volume transformation multi-pore media productivity contribution. The evaluation method comprises the following steps that firstly, based on the principle of effective stress and flow characteristics of a transformation zone, and a fluid-solid coupling mathematical model of interaction between a geotechnical deformation field (stress field) and a fluid flow field (seepage field) of the unconventional reservoirs is established; then a perfectly coupled method solution of the seepage field and the stress field is realizedby solving a fluid-solid perfectly coupled system of partial differential equations in a general formula mode; and finally, fluid-solid coupling interactions under different combinations of pore mediaare simulated, and the contribution ratio of three systems of base materials, natural cracks and grid cracks to the cumulative production of a volume transformation well is obtained. A set of evaluation method for unconventional reservoir volume transformation multi-pore media productivity contribution is established eventually. The evaluation method for unconventional reservoir volume transforming multi-pore media productivity contribution has the advantages that the model factor consideration is comprehensive, the evaluation method is simple and results are quantifiable, an oil and gas field can be guided timely to be subjected to development measure adjustment and comprehensive management, and a theoretical basis and technical support are provided to the unconventional reservoir to realize economic recovery.

Description

technical field [0001] The invention relates to the field of oil well development, in particular to an evaluation method for productivity contribution of multi-porous media in unconventional reservoir volume reformation. Background technique [0002] Unconventional oil and gas reservoirs such as tight oil and gas reservoirs and shale oil and gas reservoirs have low single-well productivity and are difficult to produce effectively. The reservoirs are complex, heterogeneous, and have extremely low permeability, and effective development faces great challenges. Volume fracturing technology, as an effective way to develop such unconventional reservoirs, is to increase the stimulated volume of reservoirs by forming a spatial fracture network in which multi-stage natural fractures and artificial fractures are interlaced, so as to achieve the purpose of increasing production. During the development of unconventional reservoirs, the pore space is very different from that of conventi...

AI Technical Summary

Problems solved by technology

Compared with analytical / semi-analytical methods, numerical methods can deal with more complex fracture network configurations and multiphase fluid flow problems, and can consider the fluid transport relationship among the three independent systems of matrix, natural fractures and artificial fractures, but only The simple coupling and superposition of each system can only obtain the overall productivity of the volume stimulated oil well, and it is impossible to quantitatively describe the respective productivity contributions of multiple porous media systems

[0005] Existing technical methods can only obtain the overall productivity of volumetrically stimulated oil wells, but cannot reveal the respective contributions of this multi-porous media system (matrix, natural fractures, and network fractures) to productivity, and thus cannot quantitatively describe and evaluate the composition of oil well productivity.

So far there is no method for evaluating the productivity contribution of multi-porous media for volume stimulation in unconventional reservoirs

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