GEOLOGY, SEARCH AND EXPLORATION OF MINERALS | |

ArticleName | Features of hydrodynamics in oil-saturated reservoirs |

DOI | 10.17580/gzh.2024.07.06 |

ArticleAuthor | Hasanov A. B., Gurbanov V. Sh., Abbasova G. G. |

ArticleAuthorData | Oil and Gas Institute, Ministry of Science and Education of the Republic of Azerbaijan, Baku, Azerbaijan
Azerbaijan State Oil and Industry University, Baku, Azerbaijan |

Abstract | Among many influences on oil and gas extraction efficiency, one of the main factors is the natural or artificially modified hydrodynamics of fluid flow in reservoirs. Even the most favorable natural hydrodynamics in the subsoil is usually complicated by unavoidable operations carried out above productive horizons and aimed to provide well performance (hydraulic fracturing, etc.). Naturally, such operations are carried out with the aim of intensifying oil and gas production, as well as increasing oil recovery factor. Under the impact of these operations, productive reservoirs, which are porous and permeable media, drop into various destructive states which are characterized by density of cracks per unit volume of rocks and by the fluid dynamics in reservoirs. This article examines the process of deformation of reservoirs with the formation of a branched system of cracks having a fractal structure, and also models the mechanism of crack formation with regard to the change in the fractal dimension of a crack system. The authors identify the stages in the crack formation process, according to which, at the initial stage of cracking, a chaotic system of cracks appears, accompanied by an increase in the fractal dimension of the system up to a value of 1.6. At the next stage, with a slow increase in the fractal dimension from 1.6 to 1.73, cracks begin to unite and form a rupture area. Further, the fractal dimension holds practically constant, and when its value reaches 1.75, discontinuity takes place in the medium. The inevitable deviations of the modeled media from the described pattern of crack formation are explained by the fact that real-life geological media most often have a certain multi-level discontinuity of the internal structure and possess defects of various hierarchical levels, which leads to fluctuations in distribution of micro- and macrostresses at these discontinuities. |

keywords | Hydrodynamics, fluids, oil reservoirs, crack systems in rocks, fractal dimension |

References | 1. Ivannikov V. I. Fluid transfer and phase zonality in distribution of hydrocarbons in sediments in the crust. 9. Egorov A. A., Gavrilenko T. V., Bykovskikh D. A. Evaluation of the parameters of fractal porous media. Bulletin KRASEC. 10.3997/2214-4609.20215701312. Barenblatt G. I. Similarity, Self-Similarity and Intermediate Asymptotics. New York : Springer, 1979. 218 p. 13. Savinskaya D. N., Nedogonova T. A. Prepregnancy analysis logistic time series based on Hurst exponent. Sovremennaya ekonomika: problemy i resheniya. 2019. No. 9(117). pp. 18–26.14. Poyarkova E. V. Fractal analysis in structural diagnostics of materials : Guidelines. Orenburg : OGU, 2019. 47 p. 15. Balankin A. S., Bugrimov A. L. Fractal dimension of fractures formed under brittle destruction of model lattices and solid states. Technical Physics Letters. 1991. Vol. 17, No. 17. pp. 63–67.16. Gelashvili D. B., Iudin D. I., Rozenberg G. S., Yakimov V. N., Solntsev L. A. Fractals and multifractals in bioecology. Nizhniy Novgorod : Izdatelstvo Nizhegorodskogo gosuniversiteta, 2013. 370 p. 17. Mosolov A. B. Fractal Griffith fracture. Technical Physics. 1991. Vol. 61, No. 7. pp. 57–60.18. Izmailova G. R., Gilyazetdinov R. A. 3D modeling of fractal characteristics of rocks. Advanced Oil and Gas Technologies–2021 : International Conference Proceedings. Ufa : Izdatelstvo UGNTU, 2021. pp. 122–125.19. Irwin G. R., Kies J. A., Smith H. L. Fracture strengths relative to onset and arrest of crack propagation : Report. Washington : U.S. Department of Commerce, 1958. 26 p. 20. Ma W., Wang Y., Wu X., Liu G. Hot dry rock (HDR) hydraulic fracturing propagation and impact factors assessment via sensitivity indicator. Renewable Energy. 2020. Vol. 146. pp. 2716–2723. |

Language of full-text | russian |

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