Ultra-deep gas reservoirs are becoming a common target in drilling for gas. Unfortunately, most of these reservoirs are highly pressured and extremely hot and have posed a great challenge for the oil and gas industry. Due to the large amounts of hydrocarbon reserves in these areas and growing demands of global energy, operators are investing more time and money into these types of reservoirs.
Challenges such as lack of downhole measurement tools in higher temperature and pressure and drilling fluids behavior under HPHT conditions may result in the wellbore stability issues and well control difficulties that put the safety of the personnel and operations in jeopardy.
Proper drilling fluids selection and applying the right temperature and hydraulic modeling plays a crucial role in the success of these operations, and helps reduce/mitigate the risk of the operations and non-productive time (NPT). This includes: ECD managements, surge/swab analysis, bit hydraulics optimization, fluid compressibility analysis and all other hydraulics and temperature factors affecting the operations.
This paper reviews successful applied modeling and fluids management methods based on proper data gathering and utilizing the best practices results in safe and successful drilling in such hostile environments.