Interpretation of electrical (EL) and electromagnetic (EML) logging is divided into two stages – the stage of geophysical interpretation and the stage of geological (petrophysical) interpretation. The stage of geophysical interpretation of logging includes a quantitative assessment of the quality of the registration curves of the complex EL and EML, point and interval interpretation (taking into account the design features of the equipment) to obtain the values of the electrical resistivity of the formation of the apparent resistance curve and the static potential of the logging curve of spontaneous polarization (PS). The result of the interpretation of the EL and EML data is the electrical resistivity of the formation, the penetration zone and the relative diameter of the penetration zone. The result of interpretation of PS logging data is the value of static potential. The stage of geological interpretation is carried out on the basis of petrophysical models of electrical resistivity and diffusion-adsorption potential of the reservoir and the values of electrical resistivity and static potential of the reservoir, obtained from the results of geophysical interpretation within the model of electrodynamics of the continuous medium.
The paper deals with the issues of automated interpretation of data of domestic and foreign complex of EL and EML, the original method of calculating the coefficient of oil and gas saturation and specific absorption capacity of clayey terrigenous reservoirs on the basis of combining the method of spontaneous polarization and methods of electrical and electromagnetic logging. The proposed method of determining the specific capacity of absorption, which is the lithological characteristics of the reservoir, and the coefficient of water saturation on the basis of integrated interpretation of spontaneous polarization method, implemented by hardware bigradient (divergent) logging of PS, and methods of EL and EML.
References
1. Chaadaev E.V., Razvitie teorii i metodiki interpretatsii dannykh elektricheskogo i induktsionnogo karotazha (Development of the theory and methodology of interpretation of electrical and induction logging data): thesis of doctor of technical science, Tver', 1991.
2. Shein Yu.L., Pavlova L.I., Rudyak B.V., Snezhko O.M., Evaluation of geoelectrical characteristics (of the formations exposed by wells) based on well logging data from different-type electric logging sondes (LOGWIN-EL) (In Russ.), Karotazhnik, 2009, no. 5, pp. 89–100.
3. Metodicheskie rekomendatsii po podschetu zapasov nefti i gaza ob’emnym metodom. Otsenka kharaktera nasyshchennosti po dannym GIS (Guidelines for the calculation of reserves of oil and gas by volumetric method. Assessment of the nature of saturation according to well logging): edited by Petersil’e V.I., Poroskun V.I., Yatsenko G.G., Moscow – Tver: Publ. of VNIGNI, 2003. 261 p.
4. Pantyukhin V.A., Shein Yu.L., Nadezhnost' opredeleniya UES plastov i vozmozhnosti ee povysheniya (Reliability of determination of resistivity layers and the possibility of its increase), Collected papers “Sovershenstvovanie tekhnologii interpretatsii i petrofizicheskogo obespecheniya geofizicheskikh issledovaniy neftegazorazvedochnykh skvazhin” (Improving the technology of interpretation and petrophysical support of geophysical studies of oil and gas exploration wells): edited by Yatsenko G.G. et al., Tver': GERS Publ., 1992, pp. 52–61.
5. Shein Yu.L., Pantyukhin V.A., Kuz'michev O.B., Algoritmy modelirovaniya pokazaniy zondov BKZ, BK, IK v plastakh s zonoy proniknoveniya (Algorithms for modeling the readings of logging probes in reservoirs with a penetration zone), Collected papers “Avtomatizirovannaya obrabotka dannykh geofizicheskikh i geologo-tekhnologicheskikh issledovaniy neftegazorazvedochnykh skvazhin i podschet zapasov nefti i gaza s primeneniem EVM” (Automated data processing of geophysical and geological and technological studies of oil and gas exploration wells and the calculation of oil and gas reserves using computers), Kalinin: Puvl of Mingeo SSSR, 1989, pp. 75–81.
6. Vendel'shteyn B.Yu., Ellanskiy M.M., Effect of rock adsorption properties on the dependence of relative resistance on porosity coefficient (In Russ.), Prikladnaya geofizika, 1964, V. 40, pp. 181–193.
7. Waxman M.N., Smits L.J.M., Electrical conductivies in oil-bearing shaly sand, SPE SPE-1863-A, 1968, https://doi.org/10.2118/1863-A
8. Clavier S., Coates G., Dumanoir J., Theoretical and experimental bases for the dual-water model for interpretation of shaly sands, SPE 6859-PA, 1984, https://doi.org/10.2118/6859-PA.
9. Afanas'ev A.V., Afanas'ev S.V., Ter-Stepanov V.V., A generalized model for terrigenous granular rock conductivity and the model's test results (In Russ.), Karotazhnik, 2008, no. 12(177), pp. 36–61.
10. Smits L.J.M., SP log interpretation in shaly sands, Trans. AIME, 1968, V. 243, pp. 123–136.
11. Kuz'michev O.B., Issledovanie estestvennykh elektricheskikh poley v neftegazorazvedochnykh skvazhinakh (teoriya, apparatura, metodika, skvazhinnye ispytaniya) (The study of natural electric fields in the oil and gas exploration wells (theory, apparatus, method, well tested)), St. Petersburg, Nedra Publ., 2006, 252 p.
12. Kuz'michev O.B., Theoretical grounds of spontaneous polarization in oil and gas prospecting wells: from homogeneous to heterogeneous according to medium resistance (In Russ.), Geologiya, geofizika i razrabotka neftyanykh i gazovykh mestorozhdeniy, 2013, no. 9, pp. 37–42.
13. Shein Yu.L., Snezhko O.M., A solution of the direct and inverse problems in the spontaneous potential technique for the formation bundle. A practical application (In Russ.), Karotazhnik, 2016, no. 9(267), pp. 156–171.
14. The certificate of registration of the computer program no. 2004611119, Opredelenie podschetnykh parametrov na osnove sovmestnoy interpretatsii dannykh karotazha PS i elektrometodov GIS dlya starogo fonda skvazhin (IntREst) (Determination of calculation parameters on the basis of the joint interpretation of SP logging and electrical methods data for old wells (IntREst)), Authors: Kuz'michev O.B., Baymukhametov D.S., Livaev R.Z.
15. Kolonskikh A.V., Mikhaylov S.P., Murtazin R.R. et al., Some specific features of dielectric logging and experience of its application at oil and gas deposits in the Western Siberia (In Russ.), Neftepromyslovoe delo, 2018, no. 12, pp. 46–52.
