Estimation of geocell permeability based on small-scale sedimentary structures in the Brent Group on the Gullfaks and Oseberg fields

Supervisors: Jan C. Rivenæs and William Helland-Hansen

 Project funding: Statoil 

Permeability is very difficult to estimate, mainly because it is very scale- and direction dependent. For instance, from permeability measured in core plugs to permeability estimated from well tests, there is a big difference in scale. How to compare these correct and apply  further in reservoir computer models, is a difficult matter.

The aim for the thesis is to improve the understanding of permeability computations as a function of small-scale sedimentary structures (centimeter- to meter scale). Small-scale structures may have a big influence on how the fluids flow in a reservoir. Modeling these structures may enhance our knowledge about the influence these structures have on permeability, and thus the influence on hydrocarbon production.

The project involves elements from sedimentological descriptions,  petrophysical measurements (well logs, lab. analysis), and reservoir technical considerations, seen from a geological point of view. The data applied in this work comes from Gullfaks and Oseberg, where Statoil recently has made updated reservoir models for the Brent Group reservoirs. The goal is to suggest improvements in the permeability modelling for these fields. Modeling the small-scale structures in the software SBED is an important part of the project.