ABSTRACT:

With the introduction of a new LWD tool, it has now become possible to acquire reliable formation pressure and mobility data during short breaks in the drilling process. Formation pore pressure and near wellbore mobility are key parameters for reservoir description. Traditionally, this data has been acquired with wireline formation testers, upon reaching section or well TD. Apart from the traditional applications of such data for gradient and fluid contact determination, real-time knowledge of pore pressure ultimately allows optimizing ECD management, increasing ROP, and improving safety. It also aids in assessing reservoir connectivity, improving casing plans, and supports other means of geosteering.One of the greatest challenges facing wellbore construction are unexpected variations in formation pressure and mobility in a given hole section. Properly identifying the hazards of pressure profile changes can assist in the decision making process and lower the risk associated with drilling ahead based solely on modeled data. Providing this type of formation evaluation data in an LWD environment allows for a continuous approach to data evaluation and decision making. The paper discusses the design and the operation of a new LWD formation pressure tester (TesTrakTM). The new LWD service was used in conjunction with traditional Pore Pressure Prediction algorithms for successful and safe mud weight management in a challenging environment offshore Egypt. The application discussed is the first LWD formation pressure tester run in the Mediterranean area in a difficult, vertical exploration well: tight formations (< 0.5 mD/cP), high temperature (> 120°C) and high mud weight (>2 sg)

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