The GeoCquest Field Validation (GFV) project will for the first time monitor the migration of a CO₂ plume through an observation well where gas saturation will be measured using high-resolution pulse neutron logging. CO₂ plume migration and trapping will be predicted pre-injection and post-injection using the observational data. The project is part of CO2CRC’s Stage 4 Program and involves researchers from The University of Melbourne and Stanford University (USA).

The prediction of CO₂ migration has been shown to be notoriously difficult particularly in heterogeneous reservoirs due to the uncertainty in rock type distribution and sub-metre scale heterogeneity. The latter is not accounted for in conventional grid cells which are often at a scale of 10s of meter in horizontal and several meters in vertical direction. A number of different geo-models have been developed for the Paaratte Sequence 2 at the IOTC. These models are based on different modelling approaches (object-based, sequential indicator simulation), differ in grid cell sizes and partly include composite rock types and their properties accounting for small-scale heterogeneity. The different geo-models are the framework for the simulation of CO₂ migration and trapping leading to large differences in the CO2 migration behaviour. We expect models with small grid cell sizes and composite rock types will predict CO₂ migration more accurately, however, the model domain requires to be relatively small due to the large number of grid cells. Ultimately, the comparison to the GFV field experimental results will indicate which type of model is most suitable for modelling the migration of CO₂ in heterogeneous reservoirs.