The study area lies around the petroleum provinces of the Egyptian Offshore Nile Delta basin. The existing exploration data are sparse, and any effort made on the strati-structural interpretation is challenging for exploratory drilling campaigns, even with meager well control. Keeping in view the issues and major challenges, the authors propose new methodologies, tools and new insights into the interpretation of the existing data and information, to make the study area more attractive for investors and detailed exploration studies. The published geological work existing within the vicinity of the study area is an added value to the new insights of current interpretation and knowledge acquisition. PliocenePleistocene section is the main target in the study area, since it has quality reservoirs, holding commercial hydrocarbons. Pre-salt source rocks may have charged the reservoirs in the study area. Structural complexities and heterogeneities at target levels are likely to impact the seismic wavelet property intricacies and thus the data processing qualities. Post-and pre-salt tectonics in the northern part of Sinai, the Nile Cone, and how they affect the structural framework and the seismic interpretation work in the study area are described. For the purpose of understanding the combinational trapping mechanism, stratigraphic features and the structural geology are integrated using new tools and technologies. Several strati-structural plays are interpreted in the study area that support the detailed exploration campaigns, and the existing major hydrocarbon plays associated within shelf, slope and deep-marine geological events in nearby offshore regions. Diapir salt, rotated fault blocks and growth faults within syn-sediment systems are other plays to be investigated. The study is an effort of compiled work from many published sources, putting all ideas into a positive perspective and has better understanding of new opportunities, leads and prospects for investment purposes in the Nile Delta offshore basin.

The shallow clastic section in the Nile Delta is characterized by mild velocity variations. The relationship between the expected velocity reduction in the gas reservoir rocks and the encompassing shale is responsible for acoustic impedance contrast, predictable to a particular AVO-class. In class-3AVO, the bright spot is a result of great reduction in velocity increase due to differences between high-velocity encompassing shale and relatively low-velocity reservoir sand. The class-3AVO characterizes a strong seismic amplitude appearance in the full stack section and with similar characteristic view of AVO analysis and interpretation. In addition to the strong amplitude, there are different DHI features related to the gas occurrence. These DHI features are analyzed to achieve and deliver a successful exploratory well. The DHI analysis of one of the unsuccessful cases using recent 3-D seismic data clarifies the importance of the workflow that works for exploring types of anomalies in the Nile Delta. The anomaly is drilled mainly based on an explicit high-amplitude anomaly with local flat spot, but without taking into consideration the extent of DHI characteristics, inherent to gas occurrence in the Nile Delta. Authors investigate all the features related to this unproven case in the form of a postmortem and compare it with proven existing discoveries, to know the possible reason of unsuccessful DHI anomalies in the Nile Delta.

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