Structural Geometry of Faulting in the Nile Delta: Implications for Hydrocarbon Traps

Alastair Beach, Phil Trayner

Pliocene-Pleistocene sediments of parts of the Nile delta are strongly faulted by north-dipping listric extensional faults. Both fault surfaces and rotated fault blocks are imaged on seismic data, and interpretations of fault geometry have been tested by fault restoration techniques, construction of balanced sections, and analysis of fault displacement gradients along faults. Hanging wall profiles provide the basis for the reconstruction of fault surfaces and depth to detachment calculations. These methods define more clearly the geometry of potential hydrocarbon traps and better constrain the stratigraphic interpretation of the area. The analysis demonstrates both the importance of transfer faults separating different fault compartments and detachment faults separating d fferent levels, enhancing prospectivity by isolating additional closed structures.

In many respects the Nile delta structures are like those found along the U.S. Gulf Coast. The recent recognition of oil and gas potential in the Nile delta should act as a catalyst for understanding more carefully the fault and trap geometry. Examples from the excellent seismic data base will be used to illustrate the different aspects of fault geometry.

AAPG Search and Discovery Article #91032©1988 Mediterranean Basins Conference and Exhibition, Nice, France, 25-28 September 1988.