Mechanisms of Fractures-Microfaults Initiation and Propagation, West-Central Sinai Peninsula, Egypt
Abdelwahab Noufal1* and M. Dia Mahmoud2
1Cairo University, Egypt
2GEOPEX Limited, Egypt
The Suez rift basin is accompanied by many fractures and small fault swarms that are smaller in scale than 1.0 m. They play an extremely important role in hydrocarbon-trap integrity and related exploration risks, as well as controlling most of the geomorphologic features that are manifested along the Gulf of Suez. In this study the fractures and the microfaults were analyzed in the area that extends from Wadi Sidri to Gebel Abu Lasaf, on the eastern side of Sinai Peninsula and along the Gulf of Suez. An outcrop-based analysis of the fracture and microfaults architecture, along the well-exposed rocks, was undertaken to determine the controls and the predictability of fracture elements. The aim was to provide a guide for subsurface fracture and microfault swarms as well as a means to predict damage zone prediction. The fracture analysis revealed that the variation in the fracture spacing is often proportional to bed thickness. The spatial distribution of faults, hybrid fractures and pure open-mode fissures with wide variations in strike, appear to be related to their location relative to the center of the Suez Rift initiating stress tensor. Most fractures and microfaults in the Gulf of Suez have a strike that trends NE (oblique to the spreading-normal direction), whereas those with Gulf-trends are less common. Most of the rock units are dominated by the NE- to EW-trending fracture and microfaults; however the Eocene rock units, Nukhul and Rudeis formations, show the dominance of the NW trend. This pattern may be related to the events that affected the Gulf of Suez rift basin.
AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain