Brittle deformation of carbonate reservoirs was characterizedrnby applying advanced visualization and interpretationrntechniques to 18 recent 3-D seismic surveys in Abu Dhabi.rnThe excellent data quality afforded a unique opportunity tornintegrate the broad range of observed structural styles andrndetailed structural geometries into a unified tectonic model.rnThis resulted in a better and more thorough definition of thernstructure and hydrocarbon distribution of Abu Dhabi in therncontext of the entire Arabian Platform.rnThe observed structures resulted from gentle basementrninversion, salt-tectonics, and detached thrusting. The N- andrnNE-trending anticlines that form the giant onshore fields grewrnduring Late Cretaceous, basement-involved forelandrninversion. Systematic sets of remarkably linear, small-offsetrnconjugate fault zones, oriented approximately N75W andrnN45W, cross the antliclines at high angles to the axial traces.rnThe consistent orientations and shear sense of the fault zonesrnsuggests they result from regional WNW-ESE compression,rnwhich also drove late Cretaceous inversion and fold growth.rnDevelopment of the salt-related anticlines was influenced byrnthe same late Cretaceous compression, as well as multiplernepisodes of salt movement. Both sets of anticlines share thernregional fault trends, but the salt-related fault zones have morernvariable orientations and timing. Mechanical stratigraphyrnclearly influences fault zone spacing, offset, and segmentation,rnboth laterally and vertically. Interpretations of the fault zonesrnas single fault planes underestimate their geometricrncomplexity. The key to unravelling and communicating therngeometric complexity is making use of a combination of datarnoptimization and advanced 3-D visualization andrninterpretation techniques. Quantification of the orientations,rnsegmentation, offset magnitudes, and spacing of the faultrnzones provides a foundation for defining their implications forrnfluid flow within the reservoirs.
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