A calculation method for predicting proppant embedding depth considering shale softening

Abstract

The invention relates to a calculation method for predicting the embedding depth of proppant considering the softening effect of shale. The self-absorption depth-soaking time curve was obtained; the standard cores under different soaking times were dried and then subjected to nano-indentation experiments on the surface respectively to obtain the Young's modulus-soaking time curve of the core surface; the softening layer was established by the finite element method. The proppant embedding model is obtained; numerical simulation is carried out to obtain the embedding amount-soaking time curve: the calculation formula of the proppant embedding amount considering the softening effect is obtained. The assumptions considered by the numerical model of the present invention are closer to reality, and the simulated and predicted fracture width values ​​under different softening conditions have a high fit with the measured values, and at the same time have strong flowability, which can be used for actual shale reservoirs. Accurate and efficient prediction of fracture width after layer hydraulic fracturing.

Description

technical field [0001] The invention relates to a calculation method for predicting the embedded depth of proppant considering shale softening, and belongs to the technical field of oil and natural gas development. Background technique [0002] Shale gas has gradually become a hot spot for unconventional natural gas exploration and development in the world. However, shale reservoirs have poor physical properties such as porosity and permeability, and hydraulic fracturing is required to obtain industrial production. At the same time, the fracturing fluid injected into the formation by hydraulic fracturing is difficult to flow back out of the formation after the construction, and a large amount of the fracturing fluid retained will be in contact with the formation rock for a long time. Therefore, it is necessary to study and analyze the calculation method of the embedded depth of proppant under the action of shale softening, which is of great significance for the optimization ...

AI Technical Summary

Problems solved by technology

However, the existing numerical models ignore the influence of formation fluid for simulation, and the current hydraulic fracturing construction of shale gas wells injects thousands of cubic meters of fracturing fluid into the formation. The calculation method will play a role in advancing the research on the width of artificial fractures produced by hydraulic fracturing of shale gas wells

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