Working together for Successful Drilling through a Fault: Risk Management, Planning and Execution

Yanez_Banda, M. (Schlumberger) | Ruzhnikov, A. (Schlumberger) | Kasimin, A. (Schlumberger) | Husien, M. (Schlumberger) | Malagon, C. (Schlumberger) | Al-Wahedi, K. (ADMA-OPCO)


Since the start of drilling campaign at new field in the United Arab Emirates the operator faced the challenge to drill across faults, what can lead to well control, wellbore instability, total losses and stuck pipe. To minimize the impact, a risk management plan was developed and implemented during drilling and completion stages, which allowed to execute wells in trouble-free manner. The operator gathered the respective teams (geomechanics, seismic, operation geologists, drilling engineering and operations) and service companies with the objective of understanding the nature and potential operational impact of the faults. Afterwards, a very detailed risk management plan (RMP) was developed, which included different options with mitigation measures on how to deal with losses. This included changes in the well design, drilling fluid, BHA and casing setting depth. The compromises and benefits of each scenario was worked until a primary option was determined. Also, detailed procedures in case of nonstandard situations were developed with contingencies. Based on the measures developed as part of the risk management plan the drilling of the sections through the fault and completion (casing run, cementing, etc.) were conducted in trouble-free manner. The prevention measures were implemented as per plan, what allowed to avoid mitigations measures and there was no nonproductive time associated with fault.