Advanced Method for Estimating Gas Migration Rates in Pressurized Mud Cap Drilling

Abstract Gas migration in oil and gas wells presents significant operational and safety risks, particularly during Pressurized Mud Cap Drilling (PMCD), a specialized Managed Pressure Drilling (MPD) technique. Accurate estimation of gas migration rates is essential for maintaining well control and preventing hazardous events such as blowouts. Traditional methods, including the Taylor bubble model and shut-in formula, often yield inaccurate results due to oversimplified assumptions. This paper introduces a novel methodology based on operational diagnostics, including flush cycles and pressure monitoring, which allows for real-time estimation of gas migration behavior. This advanced method is specifically designed for application in PMCD environments, improving situational awareness and enhancing the decision-making process under complex wellbore conditions.