Methodology for Intercepting Uncased Boreholes Using Combined Ranging Techniques and Advanced Survey Management

Abstract Objectives/Scope Accurately intercepting an uncased borehole in complex and uncertain subsurface environments requires a structured approach that leverages both high-resolution ranging data and rigorous survey management. This paper presents a novel methodology that integrates multiple ranging techniques—passive magnetic, active magnetic, and acoustic—with advanced survey management processes and relative wellbore trajectories control workflows. The objective is to establish a repeatable, robust framework for uncased borehole interception that is adaptable to diverse geological and operational contexts. Methods, Procedures, Process The proposed process begins with the concurrent deployment of passive and active magnetic ranging systems to establish continuous vector guidance toward the target borehole. Acoustic ranging complements this by refining distance and azimuth data in low-magnetic-contrast or noisy environments. The methodology incorporates advanced survey correction algorithms, including Multi-Station Analysis, in-field referencing, and sag correction modeling, but also advanced survey management techniques in a magnetic environment. Real-time integration of all ranging data into the trajectory model allows for continuous optimization of the interception path relatively to the targeted wellbore. The approach also emphasizes trajectory resilience through multi scenarii-based survey planning and dynamic uncertainty modeling. Results, Observations, Conclusions The methodology enables precise borehole interception by transforming real-time ranging inputs into actionable trajectory adjustments. Key outcomes include improved directional control, reduced interception uncertainty, and enhanced adaptability across a wide range of subsurface conditions. The integration of multiple ranging modalities ensures redundancy and confidence in positional awareness throughout the approach phase. Performance validation demonstrates sensible improvement in positioning accuracy compared to single-technology approaches, with significant reliability improvements through systematic integration protocols. Novel/Additive Information This framework is the first to systematically integrate all three commercially available ranging techniques—passive magnetic, active magnetic, and acoustic—into a unified interception workflow. The combined use of these techniques, underpinned by advanced survey management protocols, defines a new benchmark for planning and executing open-hole interception campaigns. The methodology establishes synergistic technology integration that creates performance capabilities exceeding the sum of individual technology contributions.