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


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June 28, 2022

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