Tracer-based interwell Sor-monitoring and evaluation of efficiency in EOR-methods


Mario Silva
Tor Bjørnstad
Sissel Opsahl Viig


The National IOR Centre of Norway, Sor-monitoring, EOR, oil saturation, IOR


A partitioning inter-well tracer test (PITT) determines the residual (or even remaining) oil saturation (SOR) in the flooded region between well-pairs. This type of tracer test can be used to identify improved oil recovery (IOR) targets, evaluate IOR projects, evaluate enhanced oil recovery (EOR) methods, and improve reservoir description for efficient hydrocarbon production. Thus, the main objective of the work with inter-well oil/water partitioning tracers developed within the framework of the IOR Centre is to provide tools and methodologies to improve reservoir description for efficient management of resources.

The present report aims to provide insight to its users on the deployment of tracer technology in the inter- well region of water-flooded reservoirs to determine SOR. In turn, this parameter can be used as basis to evaluate the efficiency of several oil-production related operations. It will explain workflows, expertise, and tools needed as well as the importance of the information obtained, and methods to obtain it.

This report is directed towards operators, primarily to reservoir engineers and reservoir managers, and service companies, particularly those already engaged on the deployment of tracer technology or those who aim to begin this activity. R&D personnel working in both operators and service companies may also benefit from the contents of the present report.

Author Biographies

Mario Silva


Tor Bjørnstad


Sissel Opsahl Viig

Deputy Head of Department


Cooke, C.E.J., 1971. "Method of determining fluid saturations in reservoirs" (US Patent 3,590,923). Esso Production Research Company, USA.

Deans, H.A., 1978. Using Chemical Tracers To Measure Fractional Flow And Saturation In-Situ, SPE Symposium on Improved Methods of Oil Recovery. Society of Petroleum Engineers, Tulsa, Oklahoma, pp. 10.

Dugstad, O., Viig, S., Krognes, B., Kleven, R. and Huseby, O., 2013. Tracer monitoring of enhanced oil recovery projects. In: A. Haugan (Editor), Tracer 6 - the 6th International Conference on Tracers and Tracing Methods. EPJ Web of Conferences. E D P Sciences, Cedex A.

Hartvig, S.K. et al., 2015. Use of a New Class of Partitioning Tracers to Assess EOR and IOR Potential in the Bockstedt Field.

IEA, 2021. Global Energy Review 2021, IEA, Paris.

Jin, M. et al., 1995. Partitioning Tracer Test for Detection, Estimation, and Remediation Performance Assessment of Subsurface Nonaqueous Phase Liquids. Water Resources Research, 31(5): 1201-1211.

Muggeridge, A. et al., 2014. Recovery rates, enhanced oil recovery and technological limits. Philosophical transactions. Series A, Mathematical, physical, and engineering sciences, 372(2006): 20120320.

NPD, 2021. "Facts about oil production"., accessed on 19.09.2021.

Sanni, M. et al., 2018. Pushing the envelope of residual oil measurement: A field case study of a new class of inter-well chemical tracers. Journal of Petroleum Science and Engineering, 163: 538-545.

Serres-Piole, C. et al., 2012. Water tracers in oilfield applications: Guidelines. Journal of Petroleum Science and Engineering, 98-99(Supplement C): 22-39.

Shook, G.M., Pope, G.A. and Asakawa, K., 2009. Determining Reservoir Properties and Flood Performance From Tracer Test Analysis, SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, New Orleans, Louisiana, pp. 19.

Silva, M., 2021. Development of new oil/water partitioning tracers for the determination of residual oil saturation in the inter-well region of water-flooded reservoirs, University of Stavanger, Norway, 254 pp.

Silva, M., Stray, H. and Bjørnstad, T., 2018. Stability assessment of PITT tracer candidate compounds: The case of benzyl alcohols. Journal of Petroleum Science and Engineering, 167: 517-523.

Silva, M., Stray, H., Ould Metidji, M. and Bjørnstad, T., 2021. Variation of the partition coefficient of phase-partitioning compounds between hydrocarbon and aqueous phases: an experimental study. Fuel, 300: 120915.

Tang, J.S., 1992. Interwell Tracer Tests To Determine Residual Oil Saturation To Waterflood At Judy Creek Bhl'a'pool. PETSOC-91-04-01, 31(08): 12.

Tang, J.S., 1995. Partitioning Tracers and In-Situ Fluid Saturation Measurements. SPE-22344-PA, 10(01): 33 - 39.

Viig, S.O. et al., 2013. Application of a New Class of Chemical Tracers To Measure Oil Saturation in Partitioning Interwell Tracer Tests, SPE International Symposium on Oilfield Chemistry. Society of Petroleum Engineers, The Woodlands, Texas, USA.



June 28, 2022

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