Jornal de Geologia e Geofísica
Acesso livre
ISSN: 2381-8719
ISSN: 2381-8719
Mostafa Hussien*, Tharwat H. Abdel Hafeez, M Fathy, M. Naguib El Ghamry
Qarun-East Bahariya oil fields located in the Qarun Concessions in the proven and prolific Mubarak sub-basin and Gindi basins area, Western Desert, Egypt. The present work focuses on the structure interpretation and inversion style and its impact on the hydrocarbon entrapped oil and proceeds different traps in two basins. The Mubarak structure is a doubly plunging anticline some 50 km wide and 100 km long that trend 70°E and comprises a main northerly anticline with subsidiary subparallel folds to the south. The Gindi Basin is bounded from the north by Kattaniya highly inverted basin and from the south by Wadi El Rayan-Silla high. As to Abu Gharadig basin it is bounded from the north by Qattara ridge and from the south by Sitra platform. Both basins are separated by the Kattaniya platform. In this area oil fields producing ranging from small to large size hydrocarbon accumulation, the cretaceous reservoir deformed by series of NE-SW-trending left-stepped en echelon oblique folds, due to strike slip movement cut by ENE-WNW faults and N-S to NNW trending and NW normal faults. Inversion causes decreases the amount of overburden in the highly inverted area, which can adversely effect of the top seal and the maturation of source rocks within the underlying syn-extensional section. All geological elements (structure and stratigraphic) have been interpreted throughout the analysis of well logs and interpretation of the magnetic and recent 3D seismic data, to do Prospect generation, evaluation and to understand the characteristics of different types of the reservoir intervals, type of trap system, identifying sandstone channels and faults; as well as delineating the stratigraphic plays of good reservoirs. Synthetic seismograms have been constructed for all available wells to tie stratigraphic horizons with seismic data and to define the lateral Facies variation of the beds. Constructed many Isopach maps in the study area, to validate inversion and hydrocarbon accumulation in the time of migration. The isopach maps of Khoman and Apollonia showed thickness variation, with thinner in the highly inverted area (Mubarak inversion), but going to thick in the mild inverted area (Asala ridge) and the isopach map of Masajid showed there is no Jurassic section at the S-SE or thin section was deposited at N-NW trends of the study area, it is considering the best location for drilling in shallow targets and high risk of deep reservoir. In highly inverted areas could be produce traps which hydrocarbon charged from Khatatba source rock that caused fill to spill as Qarun field, but in case the trap formed within mild to moderate inversion and there enough top seal, some of traps partial fill that receive hydrocarbon charge from regional source rock as Yomna field. This paper presented re-evaluate ARC, ARD and Jurassic tight reservoirs, which already produce at SWQ field, starting to apply modern technical studies by supporting new seismic attributes such as Qemscan analysis how can to improve the reservoir properties (porosity and permeability). According to this re-evaluation of well data, gases, oil shoes, image interpretation and attributes analysis, there are many opportunities in these reservoirs, which have good potentiality and promising targets. The tectonic evolution and structure analysis of the study area shows great similarity to the deformation of the ‘tectonically style, which generate the oil traps, where several hydrocarbon fields have been discovered.