The well delivered a high condensate yield and a good-quality reservoir. B&S’ initial facilities study proposed an FPSO development, stripping out the liquids and re-injecting the gas into the reservoir.
Phase 1 reservoir engineering indicated a mid-case of 200 MMbbl of liquids could be recovered.
Subsequently the company has enhanced the seismic data with rock physics information derived from the Darwin East well and performed a more detailed Phase 2 reservoir engineering study. Additionally, it has reprocessed and merged the 2008 seismic data with results from the 2013 3D survey.
The Phase 2 study employed a more detailed geological and petrophysical description of the reservoir, creating a 3D model in Petrel (the Phase 1 study had used a simple layer cake model). It also incorporated results from a laboratory revaporization study and analysis from sidewall cores.
B&S’ new base case model estimates wet gas in place of 2.6 tcf (74 bcm) and recoverable condensate of 263 MMbbl, assuming no aquifer support. This upgrade has to be confirmed by successful appraisal wells. However, B&S points out that its assessment only includes the reservoir interval encountered in the discovery well on Darwin East.
Seismic interpretation suggests Darwin West is structurally higher than Darwin East and that there could be two more reservoir intervals below the main reservoir.
The company now plans a detailed assessment of the merged 3D data volume and to build an inventory of low risk, amplitude-supported prospects.