Case Studies

Australian NW Shelf Pressure Study: Browse Basin

The Browse Basin contains overpressured Cretaceous, Jurassic and Triassic strata. The uncertainty in understanding the geopressure regime in the region forms a significant exploration risk for the safe and successful drilling of offshore wells.

As modern exploration targets deeper plays below the region’s Early Cretaceous seals, an increased understanding of geopressure will be essential to predict overpressure ramps, economically plan wells, and fully understand hydrocarbon migration and trapping.

Ikon Science has worked extensively in the Southern part of the Basin and therefore have an extensively knowledge of the distribution and mechanisms of overpressure here. This knowledge can be utilized and incorporated in a full Browse Basin study.

Benefits

• Reduced drilling risk with associated time and cost savings
• Improved understanding of the regional pressure regime and its part in controlling aspects of the petroleum system, including trap integrity and reservoir quality
• A future source of quality, reliable pressure data and accompanying information

Deliverables

1. A comprehensive database of direct pressure measurements (RFT, MDT, LOT, FIT), kicks, losses and mudweights for all released wells
2. Assessing formation strength from Leak-Off Tests and other data and development of appropriate predictive algorithms for fracture gradients
3. Mapped overpressure for all main reservoirs to provide a predictive base for pre-drill pressure prediction
4. Regional compaction curves for individual shale formations
5. Understanding of the mechanisms of overpressure generation
6. Digital Database of analysed wells (including stratigraphy, lithology, temperature and pressure data); rok, xls, LAS or Access
7. Pressure distribution maps focusing on the main reservoir horizons
8. Predictive algorithms for Well Planning – Regional predictive algorithms for fracture gradient and overburden, and specific normal compaction trends to allow prediction of shale pressures
9. In-depth interpretations and case studies focusing on the drilling challenges in the basin
10. Comprehensive written report
11. Well Atlas containing single- and multi-well pressure-depth plots, Vp-Rho and CNL-Rho cross plots of analysed wells