الفهرس 
Chapter 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Pore pressure and fracture gradient estimations in oil and gas industry are critical factors for safety and success. Deep water and high-pressure Nile Delta basin non-productive time (NPT) was mainly due to pore pressure variations attributed to differences in over pressure mechanisms from Pliocene to Oligocene in relatively thin and isolated sand and shale units. Pore pressure related problems costing millions of dollars and sidetracking wells were attributed to high pore pressure magnitude up to 17 ppg, confirming complexity and heterogeneity over study area.
Egypt held 63 trillion cubic feet (Tcf) of proved natural gas reserves as of January 2021. Since 1967 and until the end of Fiscal Year 2018/19, the Nile Delta has achieved 173 discoveries in addition to drilling 387 wells with success rate of 45%. This study regionally covering different offshore basins, covering +/- 200 km laterally from west through central to east Nile Delta, EGYPT. Studied wells are recently drilled within water depth ranging between 25m up to 900m below sea level. The main purposes of this study are to introduce regional integrated pore pressure study. To fill research gaps, challenges, and frame key reasons of different overpressure mechanisms along high pressure basins. To minimize non-productive time and cost of pore pressure related problems over study area and introduce best practice to young pore pressure specialist.
Compaction disequilibrium is one of the primary causes for the development of overpressure zones, although other overpressure mechanisms were observed. In this setting, pore fluids are unable to escape naturally during deposition. This causes increased pore pressure above hydrostatic pressure. Shale porosity has often been used to estimate in situ fluid pressure. The poorly understood lateral transfer, uplifting and buoyancy overpressure mechanism was secondary causes of well control problems (kick/influx) that resulted in non-productive time in studied wells.
This study was bringing new workflow and original estimation of Nile Delta integrated regional pore pressure model that has not been done before within deep water basins. Finally, study highlighted the limitation of compaction disequilibrium-based methods to detect other overpressure mechanisms. The newest seismic acquisition and processing techniques in the future could provide enough frequency for better prediction as the high-resolution Full Waveform Inverted (FWI) seismic velocity provided a close to actual PP prediction results. However, the applied approaches were showing clear seismic differences within uncertainty range for prediction versus specific zones like Messinain of two ppg lower than logs derived and measured PP.
The available image logs of drilled wells were used to define present-day stress orientation in the Nile Delta, its predominately sub-parallel to the margin (coastline). However, sequences in the eastern offshore Nile Delta that overlie Messinian evaporites exhibit variable, though predominately NE-SW. There is no big impact of SHmax orientations on studied wells stability specially for vertical and less deviated wells.