Assiut university researches
Structural and Deformation Phases Wadi
Beririq-Wadi Mubarak, Central Eastern
Desert, Egypt
‫ال مراحل ال ترك ي ب ية وال ت شوه ية ل م نط قة وادى‬
‫ب يرارك‬-‫وادى م بارك‬-‫و سط ال صحراء ال شرق ية‬-.‫م صر‬
Hassan Sayed Hassan Abbas
‫ح سن س يد ح سن ع باس‬
Moustafa M. Youssef, Mohamed A. Hassan
‫ محمد ح سن‬،‫م صط فى ي و سف‬
Abstract:
Remote sensing enhancement techniques applied in the
current study based on available ETM+ landsat image data
and Egyptsat image integrated with field work aided by
previous lithological mapping to present new detailed
lithologic and structural map of the area. Band ratio images
(3/5, 3/1, 5/7) Sabins (1999) and (7/5, 5/4, 3/1) Gad and
Kusky (2006) and Egyptsat color composite used to
discriminate between different rock units in study area. Band
ratio images (3/5, 3/1, 5/7), (7/5, 5/4, 3/1) and Egyptsat color
composite used to detect two major sinistral strike-slip which
trending N-S (Umm Battat-Kadabora El Hamra and Kabb El
Rakab faults). The false color composite ratio images 3/5,
3/1, 5/7 with field check used to map thrust faults which
control the distribution of ophiolite sequences. The present
work also aims to study in detail the structure of Wadi
Beririq/Wadi Mubarak area in the Central Eastern Desert to
determine the deformation phases. The field studies revealed
that the rocks in the Wadi Beririq /Wadi Mubarak area can be
divided into: I- Dismembered ophiolites II- Arc Assemblage IIISyn-tectonic granite IV- Post-tectonic gabbros V- Post-
tectonic granite The Wadi Beririq/Wadi Mubarak belt is
characterized by a prevalence of NEand ENE trending
tectonic fabrics and mainly NW and NNW-oriented thrusts.
Based on the analysis of measured structural data, the area
exhibits five major phases of deformation. These
deformational phases are: The first deformational event (D1)
is represented by large scale folding and thrusting mainly topto-the-north-northwest. Major fold axes extend parallel to the
major thrust faults (NE-SW to ENEWSW) and slightly
plunging towards NE as Kadabora El Zarga syncline and
anticline, Umm Battat syncline and anticline fold and Talet
Gamra syncline. Study area is dissected and deformed by a
series of imbricate thrust sheets forming a typical tectonic
mélange. The tectonic mélange contains many isolated
masses of ophiolitic metaspilitic pillow lavas, metabasalts and
serpentinites. These imbricate thrust sheets trending mainly
NE-SW and dipping mainly to SE. The second deformational
event (D2) is represented by Beririq strike slip faults (NE-SW)
controlling the main trend of Wadi Beririq and characterized
by dextral sense of movements. Kinematic indicators along
Wadi Beririq shear zone are consistent with oblique top-tothe-north-northwest shearing. The deformation is also
partitioned into a subhorizontal dextral slip and top-to-the
NNW component. The kinematics of this shear ABSTRACT
ABSTRACT viii zone is mainly controlled by distributed
transpressional wrenching along Wadi Beririq. The third
deformation phase (D3) is represented by NW-SE directed
extension accompanied by several mesoscopic structures.
The fourth deformation phase (D4) is represented by major
strike-slip faults trending N-S. The sinistral strike-slip faults
occur in the north eastern part of study area as Umm Rus
fault, at central part as Umm Battat-Kadabora El Hamra fault,
and in the western part as Kabb El Rakab fault. The final
deformation phase (D5) is represented by N-S basic dyke
swarms. The arrangement and characters of the N-S dyke
swarm indicates that the crust was actively extending in E-W
direction.