الفهرس 
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Abstract
The clastic sediments of the Abu Madi Formation host the main gas-bearing reservoirs in the Nile Delta, Egypt. The current study integrates seismic and well logging analysis in order to shed light on the Abu Madi formation in Salma delta gas field which is located outside the Abu Madi main canyon. In the study area, Abu Madi Formation consists of sandstones, siltstones and shales which infill the subaerial channels incised during the Messinian salinity crisis (MSC). The studied interval hosts two separate channelized units. Morphologically, the lower unit consists of deeply-incised flat-filled channels corresponding to the braided fluvial pattern, whereas the upper unit comprises the shallower concave-up and shingled-filled channels of the lower-energy meandering system. The braided pattern hosts coarser materials deposited as channel sand bars, channel lags and channel-base drape sediments. Higher in the section, the meandering pattern constitutes higher proportion of fine-grained materials accumulated in the abandoned channels and floodplains. The Late Messinian Abu Madi Formation of the Nile Delta constitutes sediments deposited during the final stage of the Messinian salinity crisis (MSC). Several levels of soft sediment deformation structures (SSDS) were observed in the transgressive heterolithic fluvial facies deposited adjacent to the deep-seated faults. The most common deformation features include diapiric structures, intraformational lithoclastic breccia, small-scale normal, slump folds and liquefied beds. Such association of SSDS typically resembles to those described elsewhere as generated by complex interplay of gravity-driven and seismically-induced liquefaction processes. The reverse nature of many small-scale faults associated with normal faults and slump folds suggests shear movement of sedimentary layers with respect to the underlying strata. This association is genetically related to increasing the lateral displacement of the seismically-induced liquefied sediments. The heterolithic nature of the Abu Madi sediments as well as the scarcity of bioturbation provides the favorable conditions for the preservation of the seismically-induced deformation. The vertical distribution of SSDS, upward variation in the intensity, scale and type of deformation as well as the rhythmic alternation between deformed and non-deformed intervals imply frequent, short-lived varying intensity seismic shocks. The similarity between the studied SSDS and those described elsewhere around the Mediterranean (e.g. Foes Formation, SE Spain) suggests large-scale instability of the entire Mediterranean margins during the MSC. The pay zone sandstones are thicker on the channel margins and on the upthrown parts of the faults, whereas the sandstones in the downthrown regions are often saturated with water despite their high porosity and low contents of clays. Therefore, Salma delta-1 and Salma delta-2 wells drilled on the channel margins are the best productive wells. Four reservoir rock types (RRT) were identified based on variable petrophysical and compositional characteristics. Capillary pressure, irreducible water saturation, degree of permeability anisotropy and pore-system heterogeneity increase from RRTI to RRTIV sediments. RRTI typically hosts the quartzose sandstones preferentially accumulate at the base of the fining-upward cycles in the braided fluvial sediments. On the other hand, RRTIV comprises the clay-rich intervals that are more common in the floodplain and abandoned channel sediments.