الفهرس 
NTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The South Siwa concession is located in the western Desert directly to the southwest of the Siwa Oasis and adjacent to the Libyan border. It is a frontier exploration area, while (Conoco) Continental Sahara Oil Company explored the South Diyur and adjacent South Siwa and Dakhla blocks in the 1970s. The exploration program culminated in 1979 with the drilling of the Ammonite-1 and Foram-1 exploration wells, both of which intersected Tertiary, Mesozoic and Paleozoic strata and bottomed in commercial basement without identifying oil or gas shows.
The South Siwa Block is located on the probable northeast extension of the Kufra Basin in southeast Libya. The regional structural surface features in the South Siwa Block are the NE-trending Bahariya and Farafra anticlines interpreted as a deeply eroded and inverted Late Cretaceous Structure on the southern extension of the Syrian Arc system.
The present study was started by selecting one of 2-D seismic lines to evaluate and discuss the main problems affect on seismic records, such as (transmission loss, multiple reflection, reflection time delay and lateral velocity contrasts), after testing the optimum processing sequences have applied on all 2D Seismic data set. The new 2-D processing sequence and parameters have improved the data compared to the old processing sequence. This study shows that the using of 2-D optimal processing sequence and parameters, should enhanced exploration and development efforts in the study area.The interpretation of the subsurface is based on 40 lines of reprocessed vintage 2-D seismic. The results of the 2-D seismic interpretation helped in understanding the tectonic history of the study area. Evidences for the affecting area of study by four major geotectonic cycle{ Caledonian cycle (Cambrian-Devonian),Variscan-Hercynian (LatePaleozoic), Cimmerian/Tethyan (Triassic-Early Cretaceouc) and Sub-Hercynian-Early Syrian Arc (Turonian-Santonian)} were documented from the interpretation of the seismic data set.
The picked time values and the locations of fault segments are posted
on the base map in order to construct different two-way time reflection
maps on the tops from the oldest to youngest:
Cambrian - Ordovician, Silurian, Upper Devonian, Lower Carbonife-
-rous, Jurassic and Cenomanian ages. The faults in maps can be divided
into two groups, according to the fault trends E-W and NE-SW.
Evaluation of the reservoir rock parameters such as Porosity, Water saturation, Hydrocarbon saturation and Shale contents were only possible through using well log data sets available in this study. Properties for the multiple reservoirs encountered by the wells drilled in the study area were obtained from detailed petrophysical analyses.
For the Jurassic reservoir the effective porosity increase in the NE trend and decrease in the SW trend of the study area. Effective porosity is ranged from 18- 25%.While the water saturation increases toward the North trend and decrease toward SW and range from 60-80%. The shale content show that the amount of clay volume decrease gradually to the West trend and increa For the Lower Carboniferous reservoir the effective porosity increase in the SW trend and decrease in the North trend of the study area while effective porosity ranges from 18- 26%. The water saturation increases toward the SW trend and decrease toward NW. It ranges from 24-70%. The shale content decrease gradually to the W trend and increase in the SE part of the study area. The shale content value ranges from 2-16 %.
For the Upper Devonian reservoir effective porosity is ranged from 14-20% while water saturation is ranged from 50-100%. On the other hand shale content is ranged from 1-15%.
These petrophysical properties were mapped in order to delineate reservoir horizons, which in turn helped, along with other elements, in the promotion of the three leads interpreted from the seismic data into prospects.
Exploration plays in the South Siwa Block are a combination of Paleozoic structural and stratigraphic traps associated with prospective fairways, and possible stratigraphic traps in the Late Ordovician–Early Silurian glacial channels.