الفهرس 
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Abstract
Darfeel Field is a gas condensate field located in the Mediterranean Sea, about 30 Km off the Egyptian coast, in a water depth of about 30 m and within the IEOC North Port Said Development Lease. The cumulative production from the field is 284.925 BSCF. Started production in April 1997 and ended production in September 2008.
Seven wells have been drilled and producing from Pliocene section (Kafr El Sheikh Formation). Pliocene reservoirs in Darfeel field are mainly consists of turbidities. Pliocene reservoirs are unconsolidated clean sand with high permeability with minor vertical barriers and high horizontal permeability. Reservoirs are subdivided into three levels (Anomaly-1, Anomaly-2, and Anomaly-3 respectively from top to bottom). The most significant level for production was Anomaly-2.
The present work deals with the interpretation of the available seismic reflection data in the study area (20 Seismic lines), seismic interpretation for three levels (Anomaly-1(An-1), Anomaly-2 (An-2) and Anomaly-3 (An-3)) including interpretation for faults and horizons had been done to construct the time maps, then a depth conversion was done to construct the depth maps for all anomalies which represent the 4-way dip closure.
All wells had been drilled in the crest of the closure and produced from the two anomalies An-1 and An-2, only Darfeel-1 had been penetrated and produced from An-1, An-2 and An-3.
Seismic attributes is considered as a direct hydrocarbon indicator (DHI) whereas amplitude maps can identify the sand deposits distribution. Amplitude extraction is a post stack attribute, which plays a major role in identifying lithology, geometry of sedimentary features and depositional setting. RMS (root mean square) amplitude extraction on angel stacks volumes (full, far and near volumes) is a post-stack attribute that computes the square root of the sum of squared amplitudes divided by the number of samples within the specified window used. RMS amplitude map extracted for top anomaly 1, 2 and anomaly 3 showing the difference in amplitude between partial angle stack, AVO class 3 had expected as strong amplitude of far angle more than near one which defined as gas bearing sand for three anomalies. Reflection strength and sweetness attributes also applied to confirm the presence of hydrocarbon.
AVO (amplitude variation with offset) technique assesses variations in seismic reflection amplitude with changes in distance between shot points and receivers. AVO analysis allows us to better assess reservoir rock properties, including porosity, density, lithology and fluid content. Sand anomalies of 1, 2 & 3 are classified as AVO class Ш.
In addition, Intercept and gradient attributes and cross plots of intercept and gradient can be used to correlate the gas bearing sand anomalies with the prospective anomalies. Scaled Poisson’s ratio attribute is one of the best indicators for the presence of gas saturated sands. It shows variation based on the fluid content of the reservoir.
Finally, integration between AVO analysis, AVO attributes and conventional seismic attributes has a good impact for characterizing the sand reservoirs in Darfeel field. Also, these techniques are considered as powerful techniques for increasing the probability of success (POS) of the next prospects. It is recommended to run such attributes on the anomalies before drilling.