About this Training Course

The Middle East is not only the most prolific petroleum province in the world but it also contains the world’s most longstanding carbonate/evaporite platform with stacked carbonate formations ranging from Upper Palaeozoic to the present day. Carbonate reservoirs are very different from clastics in many aspects of their deposition, diagenetic history and resultant petrophysical character and can be particularly sensitive to subtle bathymetric changes and minor changes in environmental conditions. Due to its complex behaviour, understanding the nature of the depositional and diagenetic characteristics of Middle Eastern reservoirs is key to successful exploration and development. Using a combination of short lecture modules, group exercises, discussions and longer workshops based on Middle Eastern examples, this 5-day course will build on the existing knowledge of participants to create a detailed understanding of carbonate exploration and reservoir development. Participants will be encouraged to discuss non-confidential issues that they may have encountered in their work. The course will start with a refresher on key aspects of carbonate sedimentation, diagenesis and porosity evolution. With particular reference to the movement of the Arabian Plate, we will then explore factors that have influenced carbonate sedimentation through time, including global sea-level fluctuations and their effects on accommodation space and depositional energy, tectonic cycles, palaeolatitude, palaeoclimate, oceanic chemistry and the evolution of biota. Although of global significance, these changes will be examined with respect to the deposition and diagenesis of reservoir facies within the Arabian Gulf and the prediction of exploration targets including the identification of stratigraphic and diagenetic traps. The second part of the course will focus more on the factors that influence reservoir behaviour and fluid production in Middle Eastern carbonate reservoirs. This will include extensive examples and comparisons from key reservoirs horizons (Khuff, Arab, Thamama, Shuaiba Mishrif etc). Discussion will encompass saturations, including capillary pressures and the relationship to depositional and diagenetic pore systems; wettability in carbonate reservoirs; rock typing for input to reservoir modelling and mapping using the sedimentological model and knowledge of the pore systems. Seals, permeability barriers and high permeability streaks will be mapped using a sequence stratigraphic approach and illustrated with local examples. Finally, the course will examine the importance of natural fracture systems in enhancing permeability or providing the main reservoir volume and factors that may be locally important in influencing reservoir quality and production, specifically tar mats and bitumens which are a particular issue in the Arab D reservoirs but which may also occur locally at other stratigraphic horizons.