Exploration of the Palaezoic tight gas sands has been ongoing in Abu Dhabi since the early 1980s. The first discovery of gas in this formation dates back to this period; however commercial rates were not proven due to mechanical issues and the overall tight nature of the Pre-Khuff clastics. This formation is not only of interest as a source of gas, but also because gas shows and production from this formation have shown to be free of hydrogen sulphide.Many wells in the Abu Dhabi Pre-Khuff have resulted in good gas shows while drilling, but did not produce. The poor production test results are not surprising if we consider formation damage the low permeability of the reservoir as regional experience has shown that commercial production rates are only achievable through the application of hydraulic fracturing.Hydraulic fracturing in the Abu Dhabi Pre-Khuff formation is not without its challenges. The depth of this target creates a high pressure and high temperature environment which requires special equipment and technologies. The geomechanical properties and behavior of this formation are largely unknown in the Abu Dhabi region. In other parts of the Arabian Plate, this formation is known to be a complex geological environment with high fracture gradients, the poor consolidation and a high risk of poroelasticity. The aforementioned attributes make the Pre-Khuff formation a challenge to successfully fracture stimulate.In a recent Pre-Khuff exploration well, hydraulic fracture stimulation was successfully implemented as part of the completion strategy. This new technique resulted in the successful production test of a Pre-Khuff target at commercial gas rates. In this paper we will show how the integration of petrophysical data, core data, geomechanical interpretations, lab/fluid testing and fracture diagnostics were used to design and optimize the hydraulic fracturing treatment. We highlight key technical risks and challenges encountered during the preparation, design, execution and evaluation phases of this operation and demonstrate how these risks were mitigated and the challenges overcome.. Finally, we will discuss how these methods and workflows can be applied for the improvement and optimization of future Pre-Khuff wells.
