Well Planning Solutions Tailored to Meet Atlanta Field Directional Drilling Challenges

Abstract

Abstract Atlanta is an oilfield located offshore Brazil known for its challenging directional drilling control. Its relatively shallow sandstone reservoir requires horizontal wells to maximize pay zone drainage. The objective of this paper is to describe the planning and execution phases of a successful project in the third drilling campaign in the field. To meet the geological requirements, the proposed well plan aimed to kick off from vertical just below the conductor casing shoe. The tailored well design met the specific directional drilling needs of the operator. The phase two OD was initially drilled in 12 ¼" using a mud motor with AKO = 1.7° and then a new BHA was run in hole to under ream to 16" and then to 20". This work shared the BHAs designs and the operational strategies implemented in the project. To ensure a flawless execution, a 24/7 support team service was deployed to assist offshore operations, providing real time optimization services, such as vibration control, performance drilling and KPIs to measure operational effectiveness. A drilling automation service monitored torque and drag, and for potential borehole cleaning issues: comparing the theoretical broomstick against the actual torque and drag values automatically identified any unexpected change in the trend patterns. The drilling automation service reduced back-reaming requirements by allowing data-driven decisions. Analysis of the BHA performance in the 12 ¼" section, and the subsequent under reaming 20" BHA, yielded relevant information for similar applications. This unique well project provides the industry a different approach for offshore directional drilling in unconsolidated formations. This case study illustrates well planning solutions that decrease the operational risk of missing geological targets.