%0 Journal Article %T On the occurrence of gold mineralization in the Pala Neoproterozoic formations, South-Western Chad %+ Département des Sciences de la Terre [Univ Ngaoundéré] (UN-FS) %+ Ministère de Mines de l'énergie et du Pétrole %+ Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO) %A Tchameni, Rigobert %A Doumnang, Jean-Claude %A Deudibaye, Marambaye %A Branquet, Yannick %Z AUF PCSI 603 project and AUF-51011SU201 The AUF 419 (Agences Universitaire de la Francophonie) support %< avec comité de lecture %@ 1464-343X %J Journal of African Earth Sciences %I Elsevier %V 84 %P 36-46 %8 2013 %D 2013 %R 10.1016/j.jafrearsci.2013.03.002 %K Pan-African Fold Belt %K SW Chad %K Gold mineralization %K Au-bearing quartz veins %K Shear zone %K Hydrothermalism %Z Sciences of the Universe [physics]/Earth Sciences/MineralogyJournal articles %X The Pala region, in southwestern Chad, belongs to the northern part of the Central African Pan-African Fold Belt. It is made up of greenschist-facies schists and is characterized by bimodal, mainly mafic, magmatism. This schist unit named Goueigoudoum Series is intruded by pre- to post-tectonic plutonic rocks dated between 737 and 570 Ma and dykes of quartz. Gold is mined artisanally from alluvial deposits and primary chalcopyrite-pyrite-bearing quartz veins, brecciated and silicified zones and shear zones. The majority of the mineralized shear zones and some quartz veins generally trend N-S to NNE-SSW or NW-SE and are interpreted as extensional shear fractures related to regional NE-SW-trending sinistral strike-slip shear zones. The geological context of the Pala region clearly indicates hydrothermal fluids formed along active continental margins during collisional orogenesis, and subsequent associated fluid migration typically occurred during strike-slip events. Although the origin of fluids may be varied (magmatic, metamorphic or meteoric fluids, Proterozoic seawater, or sedimentary basin formation waters), the distribution of the mineralizations along the granitoid intrusions suggests that magmatism played a major role in the dynamics of the mineralizing fluids. %G English %2 https://insu.hal.science/insu-00809472/document %2 https://insu.hal.science/insu-00809472/file/Pala_Gold_manuscript_2012.pdf %L insu-00809472 %U https://insu.hal.science/insu-00809472 %~ OBSPM %~ INSU %~ BRGM %~ AFRIQ %~ CNRS %~ UNIV-ORLEANS %~ ISTO %~ OSUC %~ GIP-BE %~ PSL %~ OBSPM-PSL