Unlocking Stratigraphic Trapping Potential in SE Abu Dhabi

Abstract

The study area is located in the south east of Abu Dhabi, covering approximately 4,000 km2. During several prospectivity studies carried out since 2012, high exploration potential was identified for Lower Cretaceous stratigraphic traps. To resolve the Aptian subtle trap configuration and lateral seals, it was decided in 2017 to acquire a 2,146 km2, high resolution 3D seismic cube. The paper will describe the planning, acquisition, processing and current interpretation results of this seismic campaign. Prior to the 3D seismic acquisition, a parameter design study was conducted to assess the requirements for the seismic acquisition and to insure that potential stratigraphic traps can be imaged in the newly planned 3D seismic cube. The processing was conducted on a zipper by zipper basis, allowing the processing of the acquired data while the remaining acquisition was still ongoing. It was conducted in a south to north direction, allowing the interpretation of the southern most zipper first which has greatest potential according to the existing prospectivety studies. Initial interpretation results confirm the challenge to interpret actual clinoform shapes at the Aptian level. Furthermore, multiples initially obstructed the seismic interpretation. Additional processing was carried out to reduce the impact of multiple energy on the seismic events. It was observed that noise reduction was acheived after the integration of each zipper, as the velocity model was further improved with each step. Albeit with these challenges, attribute extraction has been proven to be highly valuable in defining clinoform trends due to the high quality of the acquired seismic. Based on the seismic interpretation results, an exploration campaign to unlock the potential of the Aptian and deeper prospectivity in the East of the study area has been planned. For the first time in ADNOC and the emirate of Abu Dhabi, a 3D seismic survey was designed, acquired, processed and interpreted to target stratigraphic traps as the main objective. To accelerate the exploration campaign, the 3D seismic data was processed while the acquisition was ongoing. With this strategy, an 18-month turnaround from start of acquisition in December 2017 to the spud of first exploration well in May 2019 was achieved.