Online Journal for E&P Geoscientists

Van Laer, Pierre ^*1; A. M. Ali, Shazlia ¹; Sirat, Manhal ¹; A. Al-Katheeri, Faaeza ¹
(1) EUFR, ADCO, Abu Dhabi, United Arab Emirates.

As a follow up of a previously performed basin model (O. Huvaz et al, Geo2010) in South East Abu Dhabi, a regional and an improved sub-regional model is proposed.

The objective of the regional model was to fine-tune the rock properties. It allowed also to perform thermal calibration with a more extensive dataset and to test a crustal thinning history which took into account a Late Triassic Rifting event. Finally the regional model allowed to further highlight the very strong role of the Omani foreland basin in the tilting of HC filled structures and hence volumetrically important Neogene displacement of HC along some major fill and spill migration pathways.

The sub-regional South East Abu Dhabi basin model incorporated the learning from the regional model and addressed a few shortcomings of the previous model as listed below:

-SE Abu Dhabi has a set of fault-dependent leads and prospects, investigations on the main N75W and N45W faults in terms of fault sealing capacity changes through geological times where taken into account. The main controls are the rotation of the maximum horizontal stress directed at N60W at Turonian time to N15-30E at present day and the diagenesis in the cemented damage zone.

-Tracers were introduced for the expelled component of each source rock such that the accumulated HC could be related quantitatively to specific sources. This allowed a better integration between geochemical data and basin modeling, increasing the confidence level of the model.

The basin model exercises allowed to constrain the SE Abu Dhabi Petroleum System and its complex plumbing system. Whereas some prospects and leads are situated along main hydrocarbon migration highways, some others are potentially in vertical and lateral migration shadows. Together with other risk factors considerations, an order in the exploration targets and hence strategy was defined such that value of information is maximized to de-risk exploration features further down the exploration sequence.

From the regional and sub-regional basin models, potential enhancements are listed below:

-Investigate role and influence of slab detachment under Iran on heat flow

-Reduce uncertainties on source rock thickness, richness, quality and kinetics.

-Strengthen integration between test&shows, geochemistry , basin modeling, stratigraphy and structural geology with GIS tools

-Address TSR for H2S, HC phase and composition

-Address the role of HC saturation on rock properties