Combining Tracers, 4D Seismic and Production Data to Understand Reservoir Fluid Dynamics
Inter-well tracer testing offers immediate and unambiguous results
Snorre is a large oil and gas field discovered in 1979 at a water depth of 300-350 kilometers (980 to 1,150 feet), located approximately 200 kilometers (about 124.27 miles) west of Floro in the Tampen area of the Norwegian North Sea, Norway. It has some of the largest remaining reserves in the region. It is of strategic importance for creating long-term value and activity on the Norwegian Continental Shelf (NCS).
Our customer was a major operator, and they have taken several measures to increase oil recovery and extend the productive life of the Snorre field, using production and 4D seismic data. However, it is particularly challenging to understand the flow of fluids within the reservoir due to multiple issues, such as reservoir heterogeneity that can impact the fluid flow, uncertain fluid properties, pressure and temperature variations or fluid saturation changes. Improved oil recovery (IOR) requires a thorough description of the reservoir dynamics, and they deployed RESMAN’s tracer technology, which has proven to offer accurate and reliable reservoir data.
We implemented inter-well tracer testing (IWTT) along with other methods to trace the fluids as they move through the reservoir. This has been established as a proven and efficient technology to obtain information on well-to-well communication, heterogeneities and fluid dynamics. Combining tracer-data evaluation and 4D seismic and production data as an integrated method allowed us to gain a comprehensive picture of the fluid flow within the reservoir.
At the first tracer breakthrough, IWTT yielded immediate and unambiguous information on injector/producer communication, allowing us to label water or gas from specific wells. This project demonstrated that seismic and tracer data applied in combination can reduce uncertainties in interpretations of the drainage patterns and that waterfronts interpreted independently by tracer response and seismic dimming can be successfully compared, while seismic brightening interpreted as gas accumulation is supported by the gas-tracer responses.
Tracer data can be integrated into reservoir simulation models, enhancing the accuracy of models used to predict fluid behavior and contributing to more effective decision-making and reservoir management. However, despite their effectiveness, inter-well tracer testing is underused in the petroleum industry. The data obtained from inter-well tracer testing may not be used to their full capacity as most tracer data are used in a qualitative manner. Integration of extensive tracer data, production data and seismic survey data offers a comprehensive assessment of the well. At RESMAN, we have an extensive database with records from 1986, containing over 500,000 unique data points from over 170 clients in 62 countries, offering a wealth of insight for the successful application of inter-well tracer technologies.