Designing a development drilling program for the Legendre Field required a systematic approach that incorporated the lessons learned during the exploration and appraisal drilling phase. A significant part of the planning endeavor focused on arriving at a geomechanical solution that would prevent many of the instabilities and lost circulation events from being repeated. Detailed image analysis for wellbore failure, and a systematic stress and rock strength analysis was performed to identify the optimal well trajectories and mud weights to successfully drill and complete the production wells. The results of this geomechanical analysis indicated that the stress state in the Legendre Field area is associated with a strike-slip stress regime. Horizontal wells drilled sub-parallel to the maximum principal stress are optimally oriented to ensure wellbore stability in the overburden, while using a lower mud weight within the reservoir reduces the risk of massive lost circulation.

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