Deminex (as operator for its partners, British Petroleum and Shell) discovered Ras Budran oil field in 1978. Discovery well EE 85-1 was drilled in approximately 140 ft (42 m) of water, 2.5 mi (4 km) off the Sinai coast of the Gulf of Suez. Appraisal drilling (wells EE 85-2, 85-3, and 85-4) confirmed the presence of a major field with an estimated 700 million bbl of oil in place. The field, developed from three wellhead platforms, has been producing since April 1983. To date, 20 development wells have been drilled.

The Ras Budran structure at the deepest mappable seismic reflector, the top of the Kareem Formation (middle Miocene), is a broad northeast-southwest-trending anticlinal feature with an anomalous strike nearly at right angles to the main Gulf of Suez trend. At deeper pre-Miocene producing levels, the structure is complex and consists of a northeast-dipping flank (14°-15°) broken into several blocks by northwest-trending longitudinal faults and nearly north-south-trending cross faults. The Ras Budran is limited to the south and west by major bounding faults.

Oil is produced from three units of Nubian Formation sandstone from a depth of 11,000-12,000 ft (3,352-3,657 m). The lower unit of Paleozoic age averages 10% porosity and has up to 200 md in-situ permeability. Wells completed in this unit produce up to 2,000 BOPD. In contrast, the sands of the upper two units of the Early Cretaceous have 15-20% porosity and up to 700 md permeability. Wells completed in this unit produce 6,000-8,000 BOPD.

The Ras Budran structure was formed primarily during an intra-Rudeis tectonic phase (lower Miocene). Oil migration for accumulation in the structure started in the late Miocene or Pliocene when the Santonian Brown Limestone and the Eocene Thebes Formation, the main source beds in the Gulf of Suez, reached the threshold of oil generation at a burial depth of approximately 10,000 ft (3,048 m). At this depth, the organic matter in the source beds had a high transformation ratio (0.10 to 0.15), high yields of C15+ soluble organic matter and C15+ saturated hydrocarbons, vitrinite reflectance (Ro) of 0.62%, and a time-temperature index (TTI) value of 15.

Oil migration from mature source beds in adjoining lows into low-potential Nubian reservoirs is easily explained by fault planes that acted as conduits for oil migration.

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