Abstract

Surface characteristics of rocks largely influences the estimates of oil saturation factor, displacement efficiency, and relative permeabilities. In in-situ systems, the wettability can change from hydrophilic to hydrophobic depending on the interaction between fluid (brine and oil) and pore surface. The paper shows the influence of extraction and the following stages of samples’ preparation for wettability recovery on electrical properties of carbonate rocks. Following exposure of samples to pressure and temperature, the pore space surface tends to be more hydrophobic, resistivity increases, and petrophysical relations between resistivity index and water saturation factor change.

Key words:

reservoir, wettability, porosity, water saturation, oil saturation, resistivity, formation resistivity factor, resistivity index, petrophysical equations

References

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Authors

A.M. Fadeev, PhD (Phys.-Math.), Expert in Petrophysics, Analytics of Core and PVT Analysis Department, Core Analysis Centre, LLC «Tyumen Petroleum Research Center»
42, M. Gorky st., Tyumen, 625002, Russian Federation
E-mail: AMFadeev@tnnc.rosneft.ru

For citation:

A.M. Fadeev Vlijanie vosstanovlenija smachivaemosti na jelektricheskie svojstva karbonatnyh porod nizhnevendskih otlozhenij Vostochnoj Sibiri [Impact of wettability recovery on electrical properties of the Lower Vendian carbonate rocks in East Siberia]. Neftyanaya Provintsiya, No. 4(24), 2020. pp.120-128. DOI https://doi.org/10.25689/NP.2020.4.120-128 (in Russian)