الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In this work, the detection of gas chimney and associated structures as preferential hydrocarbon migration pathways from the pre-Messinian kitchen section to the Plio Pleistocene reservoirs was testified by the numerous DHIs within the upper Pliocene Pleistocene reservoirs that are in contact with the boundaries of the gas chimneys. In addition, geochemical analysis on gas samples from targets drilled in the upper Pliocene Pleistocene indicates the presence of thermogenic gas clearly generated by pre-Messinian units. In addition to direct hydrocarbon gas indicators, gas chimney presence has been used in defining the most promising areas inside the exploratory blocks. This approach has been mainly tested in the exploration of the Plio-Pleistocene interval. Areas interested by gas chimneys are obviously not defective as regard the presence of an efficient hydrocarbon generating system.
The log curve shapes technique is very useful in identifying the paleo depositional history of the main reservoir in Baltim area and also to identify the sand zone which is impregnate with huge amounts of gases.
According to the present work, one can recommend to drill the Lower Pliocene channels in the down thrown of the main fault due to the gases migrated from the gas chimneys in the south to the north until the main fault which it considered as the seal.
In the exploration and development activity, an effective geologic/geophysical
interaction with a real methodological improvement, permits a continuous
updating and improved understanding of the target reservoir. The mutual integration between a sequence stratigraphy interpretation of well data and seismic line profiles with semi quantitative inferences, eventually resulted in a clearer and more precise picture of the Messinian Abu-Madi formation, and consequently, improved the success ratio of this subtle gas play in the Baltim fields. The information contained in this work clearly demonstrates the importance of building a sequence stratigraphic framework for an improved understanding of the depositional model and physical distribution of reservoir
properties in the Baltim Gas fields of offshore Nile Delta, Egypt.
On the basis of extended bottom borehole logging and detailed well
correlations, it was possible to recognize and describe fluvial to estuarine/shelfal facies, vertically arranged in an overall fining and thinning upward trend.
The presence of sandstone bodies at different stratigraphic levels was
related to smaller-scale regressive transgressive cycles, and/or possibly
avulsions within the regional transgressive trend of the late Messinian time. According to abrupt vertical facies changes and detailed seismic interpretation,
different stratigraphic sequences were defined and traced over more than 572
km2 .Due to the lack of enough comprehensive well data at the Messinian
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stratigraphic levels in the study area, the BN-1 well provided the base for extrapolating geological and geophysical conditions away from the well site.
Abu-Madi sediments were deposited in incised-valley environments. In such environments, reservoir quality is driven by the amount of sand within the channel fill. As the sand content increases and the shale content decreases the porosity and permeability increase.
Geological observations and information obtained from well log and core analyses in the Baltim East and North fields offshore Nile Delta, Egypt have been used to evaluate the Petrophysical characteristics and hydrocarbon prospectivity of the Messinian Abu-Madi formation.
The Abu-Madi formation in Baltim area is composed mainly of shales with two major sandstone reservoir intervals which are pay zones for gas production (the Level III Main and Level III Lower).
In terms of depositional facies, the reservoirs are interpreted to be composed of point bar sands (Level III Main) and braided fluvial channel sands (Level III Lower).
Heterogeneity of the sand bodies is a key factor controlling reservoir quality in both the Level III Main and Level III Lower. The presence of clays reduces porosity and gas saturation in the reservoir sandstones especially in the
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northern part and along the margins of the Abu-Madi Paleovalley. The best reservoir characteristics belong to the Level III Lower, which has high porosity and permeability, low shale content, and low water saturation.