Acid treatment of carbonate deposits at the Perm Region oil fields

Acid treatment is one of the most studied methods of stimulation of inflow in carbonate reservoirs. Nevertheless, enterprises are faced with the problem of reducing the planned production rates of wells after such events, which is due to geological and technological reasons. Taking them into account when planning impact and predicting effectiveness is possible by analyzing actual production materials using mathematical statistics methods. In this paper, using the example of a oil field in the southern part of Perm region, the main factors that influence the efficiency of acid treatments are identified, a number of multidimensional models are obtained that take into account their mutual influence and allow determining the result of a geological and technical measure.

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Prospects for the application of proppant hydraulic fracturing at Kashiro-Verey operational facilities Volga-Ural oil and gas province

Proceedings of OilGasScientificResearchProjects Institute SOCAR ◽

10.5510/ogp2021si200605 ◽

2021 ◽

pp. 257-265

Author(s):

S. V. Galkin ◽

◽

Ia. V. Savitckii ◽

I. Ju. Kolychev ◽

A. S. Votinov ◽

...

Keyword(s):

Hydraulic Fracturing ◽

Oil And Gas ◽

Geological Structure ◽

Fractured Reservoir ◽

Compression Pressure ◽

Intensive Development ◽

Destruction Of Rocks ◽

Highly Porous ◽

Perm Region ◽

Carbonate Deposits

The geological structure of Kashiro-Verey carbonate deposits is considered on the example of one of the deposits of the Perm Region. By combining geophysical studies of wells, standard and tomographic studies of core, the following lithotypes of carbonate rocks were identified: highly porous cavernous, layered heterogeneous porous, heterogeneous fractured porous, dense. It was found that for heterogeneous lithotypes, the porosity estimate in the volume of the permeable part of the rocks significantly exceeds 7%. Experiments on the destruction of rocks were carried out for the selected lithotypes. As a result, it was found that cracks do not form for samples of the cavernous lithotype at a compression pressure of 20 MPa. For a compacted lithotype, already at a compression pressure of more than 10 MPa, an intensive development of fracturing occurs. As a result of multiaxial loading of cores, which can be considered as analogous fracturing of the formation, wide fractures are formed, along which filtration of fluids can occur. Keywords: proppant hydraulic fracturing; X-ray tomography of the core; porosity; permeability; fractured reservoir; oil deposit; carbonate deposits.

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Effect of Effective Pressure on the Permeability of Rocks Based on Well Testing Results

Energies ◽

10.3390/en14082306 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2306

Author(s):

Evgenii Vasilevich Kozhevnikov ◽

Mikhail Sergeevich Turbakov ◽

Evgenii Pavlovich Riabokon ◽

Vladimir Valerevich Poplygin

Keyword(s):

Oil And Gas ◽

Oil Fields ◽

Well Testing ◽

Effective Pressure ◽

Field Development ◽

The North ◽

Oil And Gas Fields ◽

Gas Fields ◽

Perm Region ◽

Pressure Analysis

During the development of oil and gas fields, the permeability of the reservoirs decreases due to a decrease in reservoir pressure and an increase in effective pressure, as a result of which significant reserves of oil and gas remain in the reservoir. To predict the rate of decrease in oil production rates during field development and to respond quickly, it is necessary to know the law of permeability decrease with an increase in effective pressure. Existing methods for describing the change in the permeability of rocks were analyzed in the paper. Numerical analysis of the results of core studies from previously published papers and the results of field well testing on the examples of the north Perm region oil fields showed that in both cases, regardless of the type of rock and the type of reservoir, the change in permeability can be described by the same equations (exponential and power-law). Obtained equations can be used to predict changes in the permeability of terrigenous reservoirs of the north Perm region oil fields. At the same time, according to the results of well testing, an intensive decrease in permeability is observed with an increase in effective pressure. Analysis of the nature of permeability changes using the Two-Part Hooke’s Model showed that significant irreversible deformations are currently taking place in the formations of the oil fields under consideration. Predicting the change in permeability from effective pressure can allow to optimize the development of oil deposits.

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