Thesis: 4D seismic data analysis of reservoir gas movement, offshore WA
The aim of my research is to model the sensitivity of 4D seismic to changes in gas saturation, pressure, and geomechanical effects typical of North West Shelf gas reservoirs. My research goals include detecting and separating these effects in the presence of varying amounts of noise to detect and quantify gas saturation changes. These estimates will be used to develop a suitability workflow for using 4D seismic for gas projects in North West Shelf basins. I will also apply the findings of the modeling study to a real 4D dataset acquired over the Woodside’s Enfield oil field. The aim of this will be to detect and quantify changes in the gas cap as an analog for other gas projects in North West Shelf Basins.
Why my research is important
There is estimated to be more than $250B of investments planned for developing major gas fields off the North West Shelf of Australia. These undeveloped fields total over 130 Tcf of gas, with a significant natural CO2 content. Geologic complexity in gas reservoirs will likely lead to lower than desired gas recovery and, with the high CO2 content, it is likely that operators will develop sequestration projects. 4D seismic is a useful tool for monitoring gas production over time and helping to identify areas of unproduced gas, permeable pathways, and water front movement. It will also be a useful tool for monitoring CO2¬ sequestration, to ensure it remains safely stored in the reservoir over time.