Шустов Д. В. Анизотропия физико-механических свойств сланцевых пород Баженовской свиты // Известия вузов. Горный журнал. 2019. № 4. С. 55–60. DOI: 10.21440/0536- 1028-2019-4-55-60

Introduction. Anisotropic clay rocks mechanical properties determination is an important and relevant problem, because the sediments of clays, clay shales and argillites are quite often present in oil and gas fi elds. It is reported that mudstones and shales are the reason for 70–90% of all problems associated with wells stability, which is due to the peculiarities of their physical and mechanical properties. Research aims to obtain the anisotropy characteristics of rocks elastic properties based on bedded argillites core samples testing.
Methodology. Laboratory studies of argillites and shales physical and mechanical properties have signifi cant features in both core sampling and sample preparation and experimental procedure and processing methodology. These features are due to extremely low permeability, sensitivity to water-based drilling mud, and strong anisotropy of elastic and strength properties caused by their bedded structure. The experience of testing bedded argillites core samples is considered. The tests were carried out on the equipment available under the consolidated undrained loading program in accordance with ASTM standards.
Results. Anisotropic elastic properties of the rocks and their dependence on geophysical parameters were studied in the course of tests on core samples drilled along and across the bedding.
Conclusion. The elastic properties anisotropy signifi cantly aff ects both the stress-strain state when solving specifi c problems of continuum mechanics and the calculated values of the initial stress fi eld as a whole. Accounting for the anisotropy parameters obtained in this work will allow solving the problems of geomechanics as applied to bedded argillites of the Bazhen Formation.

Key words: geomechanics; anisotropy; strength; elasticity; bedding; argillites; laboratory tests; core sample.

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