Ultradeepwater wells are commonly characterized by a narrow margin between pore and fracture gradients. In these wells, even a small variation in pressure profile may lead to severe operational issues. This paper describes the drilling of high-pressure/high-temperature (HP/HT) deepwater wells through an ultranarrow pore-pressure fracture gradient (PPFG) window by means of technology application and strict procedural control.
Introduction
An exploratory well with a narrow drilling margin can be realized successfully by use of a customized design concept. Such a concept may not follow standard procedures strictly as ordinarily defined but still can fulfill the guidelines and concepts behind conventional approaches.
To apply such a customized concept, a multidisciplinary team was created to design the well through all the possible expected scenarios.
