AWE has made a new gas discovery at its Irwin and Synaphea structures, supporting its earlier massive Waitsia discovery.
According to AWE new drilling and data confirms an extensive lateral reservoir system in the Kingia formation, which supports the Waitsia gross 2C contingent resource estimate of 290 Bcf of gas.
The initial Waitsia discovery (formerly Senecio Deep) is believed to be the largest onshore discovery since the 1960s.
According to the company the Kingia/High Cliff Sandstone contingents in the Waitsia Field have gross contingent resources ranging from 65 billion cubic feet of gas (Bcf) to 1170 Bcf, with the best estimate to date sitting at around approximately 290 Bcf.
The new Irwin-1 exploration well straddles the EP320 and L1 boundary, and was drilled to a total depth of 4049 metres, with the primary target – the Dongara/Wagina sandstones – intersected at 3146 metres.
Initial analysis of the wireline logs indicates a 32 metre gas column in the Dongara/Wagina tight gas reservoir with a gas/water contact interpreted at 3085 metres total vertical depth subsea.
This is the same depth as previously contact logs for Warradong-1, 4.5 kilometres to the south.
“The common contact suggests that these two wells may have intersected the down-dip portion of a single large gas accumulation that includes both the Irwin and Synaphea structures,” AWE said in a company statement.
“AWE suggests gross 2C contingent resources of 15 billion cubic feet of gas for Irwin and 134 Bcf of gas for Synaphea.
“The up-dip portion of the Synaphea structure, located in permit L1 has not yet been drilled.”
It went on to state: “The Kingia Sandstone interval at Irwin-1 was found to be water bearing, this outcome was not unexpected as the Kingia was penetrated below the interpreted gas-water contact at Waitsia.”
“However the Kingia reservoir is thicker than that in Waitsia, located 8 kilometres to the west. This confirms the Kingia reservoir system is laterally extensive, as assumed in the assessment of the previously announced gross 2C contingent resource estimate of 290 Bcf for the Waitsia field.”
AWE managing director Bruce Clement added: “The Irwin-1 exploration well has achieved its objectives and we are now preparing to drill the Waitsia-1 appraisal well on the Waitsia gas field, later this month.”