A Regional Approach to Understanding Basin Evolution and Play Systematics in Brunei - Unearthing New Opportunities in a Mature Basin

Hoggmascall, Nick¹; Gartrell, Anthony²; Torres, Jose¹
¹XGR, Exploration, BSP Snd Bhd, Seria, Brunei Darussalam.
²Exploration, Shell Development Australia, Perth, WA, Australia.

The structural evolution and fill history of the Brunei area of the NW Borneo margin has been revised as part of a regional study aimed at exploration portfolio rejuvenation. Particular areas of focus have been:

- What is happening at depth? New insights into the deep mechanical basement architecture have helped develop a better understanding of high order deformation and deposition controls. These observations also highlight the potential for deep plays.
- What was the structural evolution of the basin and what controlled deformation? Understanding the interaction between gravity-driven delta deformation and regional compressional tectonics is key.
- What is driving the sedimentary sequence architecture? The interplay between deformation, eustacy and sedimentation is critical for understanding the sequence architecture.

Reinterpretation of the tectonostratigraphic architecture was achieved by integrating multiple data sets (esp. 2D/3D seismic, well data, gravity, DEM) and by comparisons to regional and global analogues. Reconstruction of basin deformation and fill history for key intervals is captured in a series of palaeo-geographic maps, that show active structural and sedimentary features for a given time interval, linked to 2D structural restorations and mapped key seismic horizons. Together, these products provide a basis for the development of a robust, internally consistent geological model from which new plays and prospects have been defined and assessed.

The approaches used and findings of the work are likely to be applicable to regional evaluations of deltas deposited in compressional settings or where a complex interaction between deformation and sedimentation occurs.

AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012