As part of KOC strategy to develop the technical skills of the new recruits this paper will present a series of best practices related to decision workflows during drilling of horizontal wells through a recognized multidisciplinary team which optimized the preparation level and knowledge standard for the young generation through practical workshop and in short period. The best practices identified included aspects related to reservoir management, location selection, subsurface characterization and drilling specifics. Those were the key elements in the preparation of the technical training with the support of a multidisciplinary team that proved beneficial to the decision processes and issues faced during drilling in real time workflows. However optimization of a well needs skill, knowledge, right vision and experience, hence the results of the extensive drilling campaign and different cases of horizontal wells allowed the establishment of a practical training workshop protocol using actual acquired data for the planning, follow-up and assessment of drilling operations, which is now used in Fields Development South and East Kuwait. The practical workshop encompassed two case histories of horizontal wells where good decision procedure resulted in avoiding complications during drilling and effectively optimized most of the drilling path. This practical, interactive workshop was successful in developing with an integrated framework, the necessary skills in the participants, in all technical disciplines involved, namely Geosciences, Petroleum Engineering and Reservoir Engineering, in a pioneer effort of the Greater Burgan teams, not used before in KOC for training. The impact of this workshop was to enhance the experience of the young professionals in Petroleum Engineering, Geoscience interpretation and Reservoir Management, as well as to build their integrated knowledge on horizontal drilling for the benefit of KOC, across all Directorates and possibly applicable to other oil companies.

The mature Greater Burgan field is the largest clastic oil reservoir in the world producing from multiple clastic reservoirs. With growing surface area congestion affecting rig moves, current wells are drilled with high deviation often through unstable overburden shales. Well trajectories are getting more complex, resulting in a large increase in hole instability events associated with stuck pipes, loss of bottom hole assemblies often leading to side-tracks, challenging well logging conditions and well completion operations. This paper discusses a holistic and practical geomechanical approach to solve the instability problems, based on understanding the rock failure mechanism of shale, and also discusses the implementation of an integrated solution to drill, log and complete the wells successfully. A thorough geomechanical analysis was done on several wells. Drilling data analytics helped to understand the relationship among formation instability, well trajectory and mud parameters. Lab tests (chemical and mechanical) were performed to determine the chemical and mechanical behaviour of the rock and its interaction with drilling fluid. Anisotropic shale strength tests were targeted to know the rock strength variation with respect to angle of attack. Geomechanical models were prepared and calibrated with observations of drilling problems. Based on integration of models and experiences, effective solutions were devised to implement at well planning as well as drilling stages. A combination of measured and modelled parameters suggested that multiple failure mechanisms are active to induce shale failure including (a) stress induced borehole breakouts, (b) chemoporoelastic interaction of mud and rock fluid and (c) weakening of shale bedding planes and micro fractures. A customized real-time geomechanical monitoring solution was implemented for improved drilling performance and efficient completion of new wells. Specific mud design and mud weights for drilling high angle wells (65-70 deg) were generated and used in real-time while drilling. With the help of LWD and mud logging data, real-time decisions were taken based on well behaviour to drill the wells in a single casing section. Wireline logging and lowering of completion string was completed without any resistance even after the long section of shale was exposed for several days. This entire re-engineering of the process was accepted as a cost-effective and efficient solution that is being recorded as a best practice for implementation in future wells. Integration of diverse disciplines (geomechanical, geochemical, petrophysical and drilling engineering) was successfully implemented to drill a complex well. Real-time geomechanics along with customized drilling fluid and drilling practices enhanced the drilling efficiency. This integrated solution is expected to significantly reduce non-productive time in future upcoming wells with complex well profiles.

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