Review: The Bight Basin: From Regional Context to Licence Block Evaluation
Friday, May 10, 2013
Shared Earth Models provide the foundations for the continuous capture of data and knowledge within exploration and production workflows.
The delivery of 3D plate-scale geological models developed as part of the Neftex Earth Model unlocks limitless potential for integrating proprietary industry data into regional geological frameworks and the rapid analytical basin screening and assessment of play opportunities in the subsurface environment.
By combining conventional asset-scale 3D modelling approaches with a unique method of visualising deep time, we can investigate the evolving petroleum systems of a plate-scale area using a number of techniques and carry out rapid basin screening methods. Whether it be compiling coarse clastic depositional maps for the Phanerozoic evolution of an entire region at the click of a button or instantly highlighting reservoir-seal pairs for the complete sedimentary package of a basin, we explore regional Australia and New Zealand 3D geocellular model displayed in four dimensions as dynamic and evolving tools as opposed to their conventional static and unwieldy counterparts. We can compare preservation versus deposition and the ease at which proprietary datasets such as petroleum systems data can be integrated into screening workflows is demonstrated in an analysis of source rock potential.
The importance of effectively managing large, disparate regional datasets and executing efficient and consistent workflows is highlighted in this introduction to 3D and 4D Shared Earth Models as a tool for Basin Screening.
When regions can be identified for further investigation at a more refined scale, interpretations and data from the same shared description of the subsurface can be used to populate a more detailed framework in depth by integrating seismic data and other depth constraints. In doing so, the regionally coherent geological understanding is preserved in assessing risk at the play to prospect level. With that in mind and having high graded regions within the Australia and New Zealand region, the Bight Basin becomes a favourable target for further investigation.
The Basin has had limited exploration to date, however has been exposed to a substantial seismic acquisition programme, which due to current Australian Legislation is in the public domain. This provides a framework for the Neftex Exploration Cube workflows to be implemented, creating a depth grid which captures the Neftex Sequence Stratigraphic Model and its associated mapped facies on a regional scale.
The tectonic evolution of the Bight Basin, particularly the Ceduna Sub Basin, has led to an un-proven yet highly prospective petroleum system. The understanding of this system is greatly enhanced when using 3D visualisation tools, particularly when combined with a regional sequence stratigraphic framework. Through workflows developed in house, and accessible through the Petrel platform, the user is able to asses likely maturity profiles, reservoir charge and accumulation as well as seal presence in the basin-wide area of interest, thus substantially reducing risk on potential prospects.
The generation of the Exploration Cube gives the user the ability to interrogate and analyse both the potential petroleum systems, but also the potential risk on plays and fairways within the area of interest as a first pass assessment of the exploration potential.
Author: Ed Collins
Company: NEFTEX Petroleum Consultants