الفهرس 
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Abstract
This study aims to integrate different petrophysical evaluation techniques including core samples (conventional and SCAL), wire-line logging data and mud logging data for advanced evaluation and complete picture about Kareem Formation (Middle Miocene) in Ashrafi field, Gulf of Suez, Egypt. The interpretation and modeling of these data were done by using Interactive Petrophysics software, Origin Pro 8 SRO software and Petrel software. Ashrafi is an offshore field at the South-West region of the Gulf of Suez, with the poor seismic image. It is characterized by a complex set of tilted fault blocks of Pre-Miocene (pre-rift) age covered by a thin syn-rift section. For ten potential formations in the Gulf of Suez, the hydrocarbon production from the Kareem Formation sandstone is almost 23%. Petrophysical parameters evaluated for Kareem Formation are Net-pay thickness ranges from 17 ft to about 110 ft, porosity varies from 13% to 26%, permeability from 125 mD to about 960 mD, water saturation from 19% to about 50% and shale content from about 18% to about 56%. The average core porosity value is about 17% and the average core permeability is about 800 mD, where the relationships have a good correlation coefficient of different techniques. Electrical properties such as exponent of water saturation (n) determined at overburden pressure is 1.14; it is less than the exponent at room conditions which is about 2.09. Also, the cementation factors (m) are 1.44 and 1.48 respectively at overburden pressure and room condition. The relative permeability models are exponential functions and after solving it accurately, we can determine the cross point of water saturation that is about 52.8. This gives an indication on the wettability of Kareem Formation which is neutral water wet.
The capillary pressure from the centrifuge and MICP techniques, for the Kareem Formation, was represented by the power function of the mathematical models and interpreted with the lithology. Flow zone indicator (FZI) enhancement was done by detecting the effective pore throat radius (mega pore throat). Also, the displacement pressure, the irreducible water saturation, and the reservoir quality index were determined graphically. SDR model of permeability from NMR is the best model for permeability estimation. Also, capillary pressure from NMR spectrum is created. Spectrum for NMR was modeled by a modified Gauss model and averaged for Kareem Formation, then verified with original NMR spectrum. The concept of detecting the abnormal pressure zones by integrating Dexponent with the different petrophysical parameters, based on finding out the marked changes between these curves, in addition, the change in lithological content for the studied wells. Most of the over-pressured zones were detected within shaly intervals of the studied wells. These intervals are mostly marked by a decrease in porosity and permeability, as well as an increase in resistivity and D-exponent. The high resistivity values in these intervals may be attributed to high hydrocarbon content, whereas the high D-exponent is probably due to the characteristic low rate of penetration of shaly intervals, where there is intercalation between sandstone and shale. The thickness of the overpressure zone in Ash_H_1X_ST2 well is influenced by the marl content that reaches up to 80%. The new zones of prospects in Ashrafi field were determined by integrating the different techniques with the petrophysical maps, where there are two zones at the North West (A) and another in South East (B) direction, where the probabilities for zones (A) and (B) are 0.43 and 0.34 respectively. Also, there is a lateral variation of thickness for the Kareem Formation in Ashrafi field. So, the new wells locations should be determined accurately.