الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the Western Desert, Abu Gharadig basin has the most bountiful portion of interest among hydrocarbon explorers because of the huge thickness of the sedimentary section exists in this basin and its abundance and variety of hydrocarbon existence supports, in addition to the wide area covered, (about 17500 km2 with dimensions of 60 km and 300 km ) which is bounded by Sharib- Sheiba ridge from the north, Sitra platform in the south and Kattanyia High from south east.
Amana oil field (the study area) is related to East Bahariya concession which lies in the most eastern trough of Abu Gharadig basin and occupies an area of about 1000 acres which located between: Latitudes: (29° 33` 17`` - 29° 33` 54`` N) and
Longitudes: (29° 24` 40`` - 29° 26` 40``E).
Seismic interpretation was included among the procedures of this study; after interpreting the seismic data available in this study, Amana area showed a good structural trap (horst block style) which thought to be suitable for being hydrocarbon prone. Seismic interpretation output was used as foundation for creating the geostatic 3D model. Structural maps were conducted after seismic interpretation that showed that Amana area was marked by a set of normal faults trending NW-SE.
By finalizing seismic interpretation, the interpreted faults and picked horizons were used for importing them to start the modeling process in order to create fault model and structural
model for Amana Block. The penetrated formation tops in Amana wells were used for tying with the modeled horizons in order for getting a most reliable 3D structural model.
The assessment of reservoir is mainly conducted by Analysis of well logs which resulting in identification of sedimentary section present in the field which ranges from Moghra Formation in middle Miocene age, Oligocene Dabaa shale, Eocene Apollonia Formation, (Maastrichtian-Campanian) Khoman Formation, (U. Cenomanian-Turonian) Abu Roash Formation (the reservoir in the study area) and Cenomanian Bahariya Formation. Well log analysis aided in reservoir characterization and fluid delineation. Abu Roash G bed was proved to be a good reservoir sandstone in Amana field with very low percent of clay volume (less than 10%), average porosity from 13% to 25% and water saturation of about 20%. Impermeable shale and carbonate intercalations in Abu Roash G Member worked as an excellent top and lateral seal for sandstone reservoir bed in addition to Abu Roash F carbonate.
Well log analysis was added to the structural model to apply facies and property model among the wells and extrapolate the facies in the un-drilled locations. This petrophysical distribution helped clarifying the lateral facies changes and properties variation in the reservoir. Facies distribution in Amana field showed the lateral continuity of the reservoir sandstone among the area without any stratigraphic barrier but as mentioned before there are structural barriers caused by the faults around the area. Water saturation was very low in the polygon above the lowest seen oil level (Oil Down To i.e. ODT).
Delineating the field horizontally (with an aerial extent of about 1000 acres), and identifying the reservoir vertically (net thickness ranging from 20ft to 40ft), with determining the petrophysical parameters (sand facies reservoir of porosity average about 20%, water saturation of about 20% ) all aid in calculating the quantity of hydrocarbon initially in place, about 13 million of barrels had been calculated as stoke tank barrel (STOIIP). By applying the primary recovery factor of 15%,; recoverable reserve equation produced about 1.8 million barrels.
The main issue of hydrocarbon exploration is to identify the elements and processes of the petroleum system for an area, thus, in this study, the first element of the petroleum system i.e. source rock has been evaluated and stated that Jurassic Khatatba Fm. of transitional environment is the source rock of the hydrocarbon of the study area consisting of mixed unstructured lipids and terrestrial organic matter. Khatatba source rock contains a significant quantity of oil- prone organic matter (type II kerogen) with gas- prone organic matter (type III kerogen) and believed that it had entered the oil window (defined by 0.6% Ro).
Reservoir rock in Amana field was determined based on the petrophysical analysis and formation evaluation which assigned to the middle sandstone zone in Abu Roash G Member that had been top and laterally sealed by the intercalations of shale included in Abu Roash G Member itself and overlying Abu Roash F massive carbonates.
Responsible trap in Amana Field is of structural type with a Horst style which resulted from the two boundary E-W trend normal faults from north and south of the field and bounded from east and west sides by the normal dipping which was very favorable for collecting the hydrocarbon in the container (reservoir rock).
The timing of trap formation was during Late Cretaceous time because the main structural features in Amana field appeared to have had their maximum activities during this time while the time of oil generation from Khatatba source rock has started during Santonian age and the oil expulsion has commenced during the deposition of Khoman Formation in Campanian (Late Cretaceous age) and this migration has been stopped 25 million years ago in the Miocene time. Because of the perfect gechemical correlation between Khatatba source rock and the produced oil in Amana oil field, the certainty level evaluation considered this petroleum system as a known petroleum system.