Abstract
The history of the development of the Mardie Greensand reservoir at Thevenard Island illustrates the successful integration of subsurface modelling disciplines to enable the development and optimisation of a previously discarded hydrocarbon bearing zone. This has added 20-30 MMstb of Proved Reserves to the Thevenard Island asset. In particular, the use of G2-GOCAD modelling to generate a geostatistically populated grid proved invaluable in incorporating the heterogeneity of the reservoir. Formation evaluation modelling work contributed to the understanding of the reservoir petrophysics and better hydrocarbon identification from logs. Seismic EDGE (Enhancement & Detection of Geological Events) processing allowed the stratigraphic boundaries of the reservoir to be more accurately defined. Other seismic analyses have suggested that a northern extension to the field exists. The Chevron proprietary reservoir simulator, CHEARS, was used to model the reservoir and has also provided evidence for a northern extension to the field. The model has also been used to assess the value of infill well locations, and most importantly, the potential value of secondary recovery mechanisms such as water or gas injection. Finally, horizontal drilling technology and innovative geosteering techniques have contributed to the successful drilling of a number of horizontal, sinusoidal producing oil wells. Recently, the Mardie Greensand reservoir at the nearby Cowle oilfield was exploited as a result of an integrated effort using the knowledge gained at Saladin.
