Case Study: First Deepwater Surface Applied Back-Pressure (ABP) MPD Gravel Pack Operation - Design, Execution and Lessons Learned

Abstract Recently an operator embarked in drilling its first Deepwater Appraisal well in an area of the Caribbean Sea. The well objective was to obtain sufficient quality data from target reservoirs to verify the viability of the new asset. The base plan contemplated drilling two legs utilizing a Below Tension Ring (BTR) ABP MPD system for Early Kick and Loss Detection (EKLD) and optimized Bottomhole Pressure (BHP) control. One of the well main objectives was to well test the main reservoir, for which an Open Hole Gravel Pack (OHGP) concept was selected for sand control and a Drill-In Fluid (DIF) system was designed to minimized formation damage. The lower completion run and OHGP job were planned to be executed with a column overbalanced to the pore and stability gradients, however realized bottomhole pressure condition during the drilling phase indicated that a higher effective DHMW was needed to prevent open shales deterioration and hole collapse. The adopted solution to manage the higher-pressure requirement, minimize formation damaged, optimize operation and available resources was to use MPD to run the lower completion and execute the OHGP job. Some of the challenges to overcome included, well control considerations, reverse circulation method, among others. This paper explores the challenges, planning, execution, and results of the first Deepwater OHGP operation utilizing an ABP MPD system, provides a valuable precedent for future similar applications and presents another example of how the used MPD systems can be extended beyond the drilling phase in well construction operations.