The premature breakthrough of the injected water to the producing wells leads to a drastic reduction of oil displacement efficiency and ultimate recovery. This is most typical in the case of fractured carbonate reservoirs with high-viscosity oil. The paper reviews the results of the tracer tests and conformance control operations on a water injection well of Dacnoye field operated by Sheshmaoil LLC. The study features fluorescent tracer tests performed before and after conformance control operations, thus allowing to trace both on the qualitative and quantitative levels the filtration flow patterns between two simultaneously producing targets: the Vereiskian and the Bashkirian sequences. The presented approach to the interpretation of tracer tests differs from the conventional method due to a higher accuracy of the calculated well-to-well reservoir properties and parameters of the identified flow paths. The results of the repeated tracer tests reveal that the flow patterns change when natural and induced fractures are sealed off by an injected cross-linked polymer formed by NGT-Chem-2 chemical in the process of conformance control operations on the injection well. The engineering efficiency of the conformance control operation was evaluated based on the monthly production report using GTM Analysis module within NGT-SMART software in compliance with the applicable industry and company general guidelines for calculation of engineering efficiency of geological and technical measures. The incremental oil produced due to the conformance control operations exceeded 1000 tons over 3 months which indicates displacement of oil from by-passed zones and enhanced recovery.
References
1. Sokolovskiy E.V., Solov'ev G.B., Trenchikov Yu.I., Indikatornye metody izucheniya neftegazonosnykh plastov (Indicator methods for the study of oil and gas reservoirs), Moscow: Nedra Publ., 1986, 157 p.
2. Sokolovskiy E.V., Issledovanie zavodneniya neftyanykh zalezhey indikatorami (Study of oil flooding by indicators), Moscow: Publ. of VNIIOENG, 1974.
3. Demidovich B.P., Maron I.A., Osnovy vychislitel'noy matematiki (Fundamentals of computational mathematics), Moscow: Nauka Publ., 1966, 664 p.
4. Metodicheskoe rukovodstvo po priemke, analizu i sistematizatsii rezul'tatov trassernykh issledovaniy v organizatsiyakh Gruppy “LUKOYL” (Guidelines for the acceptance, analysis and systematization of the results of tracer studies in the organizations of the LUKOIL Group), V. 1.0, Moscow: Publ. of LUKOYL, 2012, 69 p.
5. RD 39-0147428-235-89, Metodicheskoe rukovodstvo po tekhnologii provedeniya indikatornykh issledovaniy i interpretatsii ikh rezul'tatov dlya regulirovaniya i kontrolya protsessa zavodneniya neftyanykh zalezhey (Guidance on the technology for conducting indicator studies and interpreting their results to regulate and control the process of waterflooding of oil deposits), Groznyy: Publ. of SevKavNIPIneft', 1989, 79 p.
6. RD 153-39.1-004-96, Metodicheskoe rukovodstvo po otsenke tekhnologicheskoy effektivnosti i primeneniya metodov uvelicheniya nefteotdachi (Guidelines for assessing the technological effectiveness of enhanced oil recovery methods), Moscow: Publ. of VNIIneft, 87 p.
7. Chornyy A.V., Kozhemyakina I.A., Churanova N.Yu. et al., Analysis of wells interaction based on algorithms of complexing geological and field data (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 1, pp. 36–39.
8. Mordvinov V.A., Martyushev D.A., Puzikov V.I., Estimation of influence natural fracture reservoir on the dynamics of productivity of wells complex structurally oil reservoir (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 11, pp. 120–122.
9. Atanov G.A., Vashurkin A.I., Revenko V.M., On the issue of forecasting oil field development from field data (In Russ.), Problemy nefti i gaza Tyumeni, 1973, V. 17, pp. 35–37.
