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Abstract Abu Madi and Qwasim formations are the main producing horizons in Faraskour and El Basant fields respectively. Abu Madi is deposited as fluvial sediments forming network of channeling system in the Messinian part. Qwasim is divided into two zones, Pay1 (QP1) and Pay2 (QP2) and they deposited on a wide shallow marine shelf. The used seismic data are represented by part of 3D survey of PSTM volume and its far angel stack (26o-40 o). Also Bouguer gravity data is use covering wide area than the study area for finding the regional structure and investigating the basement depth through the forward 3D and 2D modelling. The used data are obtained and licensed from Danagas Petroleum Company. The studied formations are controlled structurally by faulting which forming the Miocene gas fields in the study area. The integrated use of seismic attributes (coherency, AVO modeling and analysis, and amplitude extraction) added significant information about the hydrocarbon potentiality, facies and the minor geological structures exist and controlled the new gas opportunities. The role of the gravity tools was trying to understand and delineate the possible deepseated Structure in the deeper geologic section which can’t investigate it by the surface seismic. One of the two main structure trends is obtained from The horizontal gradient (in x-direction) of the residual gravity data which showed shallow structure trend in north-South which representing the Sidi Salem faults which detached in the Oligocene section and also the other trend east-west with depths range from 3 to 6 km was recognized by the results of Euler deconvolution analysis which fit in direction with the hinge zone faults. So the second main trend which extended from east - west is the most possible trend charging the shallow reservoirs with gas as a vertical migration and increase the possibility to charge the deeper reservoirs as well. The work has been done explained clearly that there is another gas potentiality not drilled located northeast Azhar gas field and from the amplitude map and 3D volume rendering visualization looks promising gas volume closed to the volume of Azhar field if drilled the two zones QP1 and QP2 commingled with one well. The mapped horizons explained that there is pinch out or thinning toward the eastern part of the study area in Qwasim formation and in high structure which increase the possibility to find stratigraphic trapes. Gravity map of the study area shows a wide range of gravity values these gravity values are classified into two positive and negative polarities ranged between (-38 and + 62 mGal). The study area is located in the positive gravity anomalies which distributed approximately throughout the study area toward the north of Egypt offshore and the southern west part which it is characterized by negative anomalies. The modelled 2D gravity data explained that the observed high Bouguer gravity values are in agreement with the hypothesis that the oceanic crust underlying this part of the Levant Basin is denser than the surrounding country rocks which lies at the southern part of the study area in the E–W direction. This decrease in the gravity is mainly caused by the increase in sediment thickness and also due to the presence of thick continental crust of the African plate. There is a gradual change of gravity values from the south to the north, probably associated with crustal changes in its thickness. The gradual changes from the south to the north is also related to the crust composition where it differs from continental at the continental margin of Egypt to oceanic crust at the entire Levant basin. Finally the depth wise of basement could be incorrect from only the gravity tool and need help from magnetic tool and this point will be the field of research in the future in case of magnetic data is available. |