An Integrated Workflow for Improved Lateral Placement in Underbalanced Coiled Tubing Drilling Operations

Abstract This paper describes an integrated workflow that was developed to identify sweet spot and maximize lateral placement in underbalanced coiled tubing drilling (UBCTD). As fields mature and become more challenging, UBCTD becomes an effective solution to extract hydrocarbon. In some implementations, UBCTD encounters drilling challenges that result in shorter laterals or lower net-to-gross ratio than planned. Effective lateral placement precision in sweet spot is one of the main requirements to optimize productivity of oil and gas reservoirs. The constructed workflow maps key operational indicators extracted from offset wells to drive optimized well placement and maximized gas output. The workflow involves selecting key indicators from multiple offset wells to identify vertical and spatial variations. These variation profiles are generated based on a pattern and trends with highest success rates across available data. Based on the ideal productivity profile identified and the matched target well placement, the operational plan is then integrated with seismic data to boost lateral placement accuracy across the target. Developed data maps and actual gas rate are assessed to verify placement accuracy, and call for decisions to adjust well trajectory plans in real time. The introduced solution has demonstrated improvements in lateral placement by utilizing key operational indicators from offset wells data. The workflow was conducted on a synthetic thin carbonate reservoir box, where the generated stratigraphic window was adjusted based on an optimal performance data. The data collected during UBCTD operations was further inverted to enhance and improve operations. The developed workflow pinpoints operations variation and allows steering corrections to place the lateral within the expected target, where gas flow readings will confirm reliability of the operation parameters and thus model robustness and validity. The process implemented focuses on integrating real-time data to optimize predictive models and avoids drilling non-reservoir footage. In addition, the workflow accounts for time delay challenge between bit position and logging tools in the bottom hole assembly during data acquisition.