Presenter
Warren Fernandes from Baker Hughes
Co-authors
Monica Vik Constable, Kåre Røsvik Jensen, Frank Antonsen, Brice Fortier, Equinor, Warren Fernandes, David Holbrough, Hatem Oueslati, Sergey Martakov, Andreas Hartmann, Yuriy Antonov, Ulrike Piekert, Maik Linke, Ivan Nugraha Putra, Craig Saint, Henrik Andersson, Baker Hughes
Abstract
Objective/Scope:
Typical Ultra-Deep Azimuthal Resistivity (UDAR) deliverables are an inversion displayed as a “map” of fluid and / or lithological boundaries potentially up to a few hundred feet away from the well bore.
Through examples from the Johan Sverdrup field, Norway, we demonstrate how quality control and confidence analysis techniques applied to these inversion outputs are vital to quantify the uncertainties and ensure the result is transparent, trust-worthy and usable in a reservoir model.
Methods, Procedures, Process:
Prewell feasibility modeling is important to understand the value and placement requirements of individual logging-while-drilling (LWD) measurements to meet objectives.
Full tensor collocated and pure moment electromagnetic measurements enabled real-time signals, suitable for timely geosteering and geomapping with utilization of higher frequencies on the smaller spacings & lower frequencies on the larger spacings.
A combined deterministic & statistical inversion technique delivers a final model that effectively captures the balance between a mathematically optimal solution and geological conformance.
The final inversion derived reservoir map is quality controlled by applying dynamic depth-of-detection, boundary & resistivity linear confidence analysis.
Results, Observations, Conclusions:
Reservoir Mapping based on UDAR measurements provides information on reservoir distribution and quality that in turn enables optimized field development decisions for improved production & recovery.
The variance in reservoir thickness & quality could be determined and the inversion map was quality controlled. Furthermore, the results of the inversion are visualized in a way to also support more informed realtime decision making by non-domain experts.
This new combination of dynamic depth-of-detection coupled with resistivity and boundary confidence analysis provides the means to appraise the reservoir potential and geometry of both near and far features. It reduces the subjective influence of perception when making critical field development decisions and updating the reservoir model and provides a means of reconciling near wellbore measurements with reservoir scale seismic measurements.
Field experience confirms the benefits and application of confidence analysis on realtime decision making in both reservoir mapping, for example from the conductive environment to aid landing and lateral optimisation as well as enhancing the deliverable to ensure the geomodel updates encompass inversion data with quantitative confidence to deliver the highest fidelity updates to the reservoir model.
Novel/ Additive Information:
The application of the next generation of UDAR technology coupled with dynamic depth-of-detection, linear boundary sensitivity, and multi-interval inversion techniques significantly adds confidence to both the geosteering and geomapping. This delivers improved understanding and communication on the inversion confidence span supporting the integration of this geomapping data into the geomodel; driving analytical capabilities on net to gross realizations as well as hydrocarbon in place estimates computed from referencing these UDAR inversion derived reservoir maps.
Biography
Warren Fernandes is senior global product manager, reservoir mapping and navigation services, for Baker Hughes. He has been with Baker Hughes for three decades. Having started in field engineering and operations management roles, he then spent more than a decade focusing on formation evaluation across wireline and LWD domains. He also spent approximately four years heavily involved with reservoir field studies involving a wide variety of reservoir types. Since 2019 he has led legacy services in addition to the development of new services in the reservoir mapping and navigation segment for Baker Hughes, based in Celle, Germany. Mr Fernandes holds a master’s degree in geology from the university of Mumbai