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dc.contributor.authorLaukemann, Michaeleng
dc.date.accessioned2013-07-10T12:51:34Z
dc.date.available2013-07-10T12:51:34Z
dc.date.issued2013-06-03eng
dc.date.submitted2013-06-03eng
dc.identifier.urihttps://hdl.handle.net/1956/6794
dc.description.abstractDetailed fault zone and relay ramp characterization have only to some extent previously been done in carbonate rocks. This study aims to use field data to contribute a better understanding of the deformation related to normal faults and relay ramps in carbonate rocks. Specifically, the study focuses on characterization of damage zone deformation variations along normal faults, relay ramp complexity and implications for permeability and fluid flow in carbonate reservoirs. The study area is located within the Hammam Faraun Fault Block of the eastern flank of the Gulf of Suez. Here, a relay ramp, bounded by two overlapping N-S trending faults, comprising mainly Eocene pre-rift carbonate rocks, is presented. Structural data from outcrop studies form the basis of the field data. The field data display a damage zone deformation asymmetry along the studied faults, where the hanging wall is generally more deformed than the footwall, and show increased fracture frequencies in the proximity to the faults. However, occurrence of shale smear is observed to reduce hanging wall deformation. The asymmetric damage zone deformation pattern may be a result of upward propagation of the faults and because most of the fault movement is represented by downward movement of the hanging wall, while increased fracturing in the proximity of the faults is related to build up of frictional resistance in the fault core, during slip events. Decay of stress away from the faults then leads to decreased fracture frequencies. The deformation reducing effect on the hanging wall, observed by shale smear, is only a minor observation. It is therefore difficult to judge whether this is an isolated occurrence or a recurring pattern. However, the findings do agree well with other studies. The deformation along the studied faults also features mainly fault-parallel fractures with subordinate fault-perpendicular fractures. Fault-parallel fractures are a common feature along normal faults, while fault-perpendicular fractures may have formed as a result of the perturbation effect around growing faults. A fault tip zone and a branching point between two faults have also been studied. The tip zone is characterized by a splay of minor synthetic and antithetic faults which is well supported by other studies, while the branching point displays anomalously high fracture frequencies and may represent a point of single-tip fault interaction. Observations from the relay ramp show the fractures are oriented fault-parallel (N-S), fault-oblique (NE-SW and NW-SE) and fault-transverse (E-W), where cross-cutting relations reveal that the latter are the youngest. The fault-transverse fractures are therefore interpreted to reflect the latest stage of local stress field perturbation during fault propagation and overlap. At this point extreme local stress and rotation of the principal stress axes made it possible for fractures to grow at high angles to fault strike. Finally, the relay ramp is characterized by fracture frequencies only slightly elevated above background fracturing levels, indicating a lower complexity than what is expected in a relay zone based on previous studies. This is interpreted to be a result of: (1) large separation distance between the ramp-bounding faults compared to relay displacement and (2) large separation distance compared to overlapping distance. The relay ramp is therefore interpreted to be a soft-linked relay ramp, or, at the most, a soft-linked relay ramp with incipient breachingen_US
dc.format.extent7761223 byteseng
dc.format.mimetypeapplication/pdfeng
dc.language.isoengeng
dc.publisherThe University of Bergenen_US
dc.titleStructural analysis of a relay ramp affecting Eocene carbonate rocks in the Suez Rift, Egypten_US
dc.typeMaster thesis
dc.rights.holderCopyright the author. All rights reserveden_US
dc.description.degreeMaster i Geovitenskapen_US
dc.description.localcodeMAMN-GEOV
dc.description.localcodeGEOV399
dc.subject.nus756199eng
fs.subjectcodeGEOV399


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