The effect of kerogen content and maturation on physical properties of oil and gas shales
Abstract
Organic‑rich shales have long held great scientific and practical appeal, serving as effective sources of hydrocarbons. Characterizing these low‑permeability rocks is challenging due to their multiscale heterogeneity, anisotropy, and enrichment with kerogen, whose properties vary over a wide range and differ from those of rock minerals. Analyzing segmental and unsystematized published data does not reveal general trends, whereas combining these data can solve this issue. This study explores and compiles kerogen's effect on shale physical properties (elastic, thermal, mechanic, electric, etc.) using published data supplemented by new experimental data on thermal properties of Bazhenov Formation rocks. Using published data, a growing difference in kerogen's density for different kerogen types was revealed since the end of oil window. A three‑ to fourfold change in kerogen's thermal expansion at the peak oil generation temperature was identified. A positive trend in kerogen's thermal conductivity with maturation was established within the oil window. The methane sorption capacity in a dry mineral matrix is approximately five times that of a wet one. Thermal and elastic anisotropy in shales rise with increasing kerogen content during the early‑to‑peak oil generation stage. It yields cross‑correlation and enables the prediction of challenging anisotropy coefficients from a simpler determinable anisotropy coefficient. Adding new experimental data allowed for a study of kerogen's effect on thermal conductivity reduction with temperature in shales and estimations of kerogen's volumetric heat capacity. Our study highlights the directions for further research, while findings applicable to reservoir characterization and numerical modeling of hydrocarbon generation and recovery.
Document Type: Original article
Cited as: Chekhonin, E. M., Spasennykh, M. Y., Popov, Y. A., Kozlova, E. V., Popov, E. Y., Song, Z. The effect of kerogen content and maturation on physical properties of oil and gas shales. Advances in Geo‑Energy Research, 2026, 21(1): 77‑94. https://doi.org/10.46690/ager.2026.07.08
DOI:
https://doi.org/10.46690/ager.2026.07.08Keywords:
Kerogen, thermal maturity, anisotropy, multiscale heterogeneity, shale physical propertiesReferences
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Copyright (c) 2026 Evgeny Mikhajlovich Chekhonin, Mikhail Yurievich Spasennykh, Yury Anatolevich Popov, Elena Vladimirovna Kozlova, Evgeny Yurievich Popov, Zezhang Song
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