%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Ouiya, P.
%A Siebenaller, L.
%A Salvi, S.
%A Béziat, D.
%A Naba, S.
%A Baratoux, Lenka
%A Naré, A.
%A Franceschi, G.
%T The Nassara gold prospect, Gaoua District, southwestern Burkina Faso
%D 2016
%L fdi:010067639
%G ENG
%J Ore Geology Reviews
%@ 0169-1368
%K West African Craton ; Boromo Greenstone Belt ; Burkina Faso ; Orogenic gold ; Shear zone
%K BURKINA FASO
%M ISI:000378450300038
%P 623-630
%R 10.1016/j.oregeorev.2015.11.026
%U https://www.documentation.ird.fr/hor/fdi:010067639
%> https://www.documentation.ird.fr/intranet/publi/2016/08/010067639.pdf
%V 78
%W Horizon (IRD)
%X The Nassara-Au prospect is located in the Birimian Boromo Greenstone Belt in southwestern Burkina Faso. It is part of a larger mineralized field that includes the Cu-Au porphyry system of Gaoua, to the north. At Nassara, mineralization occurs within the West Bade Shear Zone that follows the contact between volcanic rocks (basalt and andesite) and volcano-sediments (pyroclastics and black shales) at the southern termination of the Boromo Belt. Gold is associated with pyrite and other Fe-bearing minerals that occur disseminated within the sheared volcanic and volcano-sedimentary rocks. In particular, highest grades are distinguished in alteration halos of small quartz-albite-ankerite veins that form networks along the shear zone. Here, pyrites are marked by As-poor and As-rich growth zones, the latter containing gold inclusions. Gold mineralization formed during D2(NA). Subsequent shear fractures related to D3(NA) related are devoid of gold. Nassara is a classical orogenic gold occurrence where gold is associated to disseminated pyrite along quartz veins.
%$ 064