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Journal of Materials Science and Nanotechnology | Volume: 3
March 20-21, 2019 | London, UK
Materials Science and Materials Chemistry
2
nd
International Conference on
The Hajjar regional transpressive shear zone (Guemassa Massif, Morocco): Consequences on the
deformation of the base-metal massive sulfide ore
Safouane Admou
University of Orléans, Morocco
T
he genesis of thebase-metalmassive sulfidedeposits hosted
within the Moroccan Hercynian Jebilet and Guemassa
Massifs is still under debate. No consensus currently exists
between the two models that have been proposed to explain
the deposits, i.e., (1) syngenetic volcanogenic massive sulfide
mineralization, and (2) synmetamorphic tectonic fluid-assisted
epigenetic mineralization. Conversely, researchers agree that all
Hercynian massive sulfide deposits in Morocco are deformed,
even though 3D structural mapping at the deposit scale is still
lacking. Therefore, while avoiding the use of a model-driven
approach, the main aim of this contribution is to establish a
first-order structural pattern and the controls of the Hajjar base
metal deposit. We used a classical structural geology toolbox
in surface and subsurface mining work to image finite strain
at different levels. Our data demonstrate that: i) the Hajjar
area is affected by a single foliation plane (not two) which
developed during a single tectonic event encompassing a HT
metamorphism. This syn-metamorphic deformation is not
restricted to the Hajjar area, as it is widespread at the western
Meseta scale, and it occurred during Late Carboniferous times;
ii) theHajjar oredeposit is hostedwithin a regional transpressive
right-lateral NE-trending shear zone in which syn- to post-
metamorphic ductile to brittle shear planes are responsible
for significant inflexion (or virgation) of the foliation yielding
an anastomosing pattern within the Hajjar shear zone. Again,
this feature is not an exception, as various Late Carboniferous-
Permian regional scale wrenching shear zones are recognized
throughout the Hercynian Meseta orogenic segment. Finally,
we present several lines of evidence emphasizing the role of
deformation in terms of mechanical and fluid-assisted ore
concentrations.
e:
admou.safouane@gmail.com