Basins Workshop 2023

December 19, 2023

Basins Workshop 2023

Congratulations to the organisers of Basins Workshop 2023 for once again producing an outstanding event that attracted great attendance. We were delighted to be able to contribute a presentation on the Offshore North Perth Basin, the much poorer cousin of the highly successful Onshore North Perth Basin.

We posed the obvious question, why so much success onshore yet very limited luck offshore despite the strikingly similar geology?

Drawing on extensive work undertaken over the years by the CSIRO Fluid History Analysis team and contained within our Cyclops fluid inclusion database we were encouraged to see GOI data pointing to widespread oil charge, derived from multiple source rocks as part of an effective petroleum system. Indeed nearly 90% of the valid drilled traps appear to have been filled with oil and once contained substantial oil volumes much larger in most cases than the only productive oil discovery offshore, the commercial Cliff Head field. Widespread trap breaching is the likely culprit that has led to limited exploration success. Solve that problem and there remains plenty of volumetrically large traps yet to drill, but choosing the right ones to drill requires better risking of trap integrity to improve the likelihood of delivering a new field discovery.

Ascendience Geoscience last year completed an 18-month detailed investigation of trap breach in a similar reactivated basin with abundant palaeo-oil columns, the Bonaparte Basin in the offshore portion of Timor Leste. That study produced a trap integrity prediction model that delivered a retrospective success rate of more than 80% when tested on the current oil fields.

A similar approach may well provide the key to unlocking considerable yet to find in the offshore North Perth Basin and perhaps this fallow, mostly open acreage, can emerge from the shadow cast by its highly lucrative onshore twin?

Ascendience is seeking expressions of interest for a multi-client regional prospectivity study in the Offshore Perth Basin to unlock the potential or equally condemn the basin due to excessive trap breach risk. For companies late to the party who have missed out on the best seats onshore a relook at opportunities in the offshore part of the Perth Basin, with a focus to mitigate trap integrity risk, could reveal viable leads and prospects of attractive size.

Get in touch to find out more or if you have interest in a multi-client study with great potential to reduce costs for new venture or M&A screening and take full advantage of our considerable trap integrity prediction expertise.    

A copy of the presentation is available for download on the Ascendience website at:

Lisk, 2023, Offshore Perth Basin