Basin-scale Modelling and Simulation for CO2 Storage: Basins in Eastern Australia

Bunch, Mark¹; Michael, Karsten; Hortle, Allison; Azizi, Ehsan; Arnot, Malcolm; Daniel, Richard (Ric); Wenz, Michael; Fernandes, Blaise; Lawrence, Mark; and Browne, Greg
¹[email protected]

Deep saline formations (DSFs) provide great potential for storing injected CO2. They contain reservoir rocks that have no presently exploitable resource within their pore system, perhaps because they lack a viable system for trapping buoyant fluids. The ultimate potential and impacts of CO2 injection into DSFs can only be assessed through dynamic simulations built on regional-scale static geocellular models. Static models must represent real geological heterogeneity of the DSF. Dynamic simulations must incorporate real hydrodynamic flow across boundaries of the DSF.

Regulation of subsurface CO2 storage requires an assessment of likely interactions between CO2 storage operations and other subsurface resources. Basin-scale static models of DSFs in the Gippsland, Otway and Surat basins of eastern Australia have been constructed for use in dynamic simulations of CO2 injection and storage. These simulations examine far-field effects of a variety of storage operations scenarios on the production of oil, gas, coal, groundwater, geothermal energy and on other competing uses of pore space basin-wide.

Comparison of simulation results with generic models suggests a combination of analytical tools – equations for calculating injection pressure, radius of impact and storage capacity – and generic numerical simulations may provide useful preliminary predictions for practicable storage capacity and injectivity at the basin scale. However, only basin/DSF-specific geocellular models and simulations can locate areas of potential resource conflict stress. Even at pilot-to-demonstration scale, analytical tools can quickly generate indicative results for maximum bottom-hole injection pressure, reservoir capacity and radius of influence. Such results should form bases and constraints for the more detailed site-specific geocellular modeling and simulation that follows.

AAPG Search and Discovery Article #90166©2013 AAPG International Conference & Exhibition, Cartagena, Colombia, 8-11 September 2013