@article{fdi:010066051,
  title = {{G}eology and geochemistry of the shear-hosted {J}ulie gold deposit, {NW} {G}hana},
  author = {{A}mponsah, {P}. {O}. and {S}alvi, {S}. and {B}eziat, {D}. and {S}iebenaller, {L}uc and {B}aratoux, {L}enka and {J}essell, {M}ark},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he {L}eo {M}an {C}raton in {W}est {A}frica is host to numerous economic gold deposits. {I}f some regions, such as the {SW} of {G}hana, are well known for world-class mineralizations and have been extensively studied, gold occurrences elsewhere in the craton have been discovered only in the last half a century or so, and very little is known about them. {T}he {J}ulie gold deposit, located in the {P}aleoproterozoic {B}irimian terrane of {NW} {G}hana, is one such case. {T}his deposit is hosted in a series of granitoid intrusives of {TTG} composition, and consists of a network of deformed, boudinaged quartz lodes ({A}-type veins) contained within an early {D}-{J}1 {E}-{W} trending shear zone with dextral characteristics. {A} conjugate set of veins ({C}-type) perpendicular to the {A}-type veins contains low grade mineralization. {T}he main ore zone defines a lenticular corridor about 20-50 in in width and about 3.5 km along strike, trending {E}-{W}and dipping between 30 and 60 degrees {N}. {T}he corridor is strongly altered, by an assemblage of sericite + quartz + ankerite + calcite + tourmaline + pyrite. {T}his is surrounded by a second alteration assemblage, consisting of albite + sericite + calcite + chlorite + pyrite + rutile, which marks a lateral alteration that fades into the unaltered rock. {M}ass balance calculations show that during alteration overall mass was conserved and elemental transfer is generally consistent with sulfidation, sericitization and carbonatization of the host {TTG}. {G}old is closely associated with pyrite, which occurs as disseminated grains in the veins and in the host rock, within the mineralized corridor. {SEM} imagery and {LA}-{ICP}-{MS} analyses of pyrites indicate that in {A}-type veins gold is associated with bismuth, tellurium, lead and silver, while in {C}-type veins it is mostly associated with silver. {P}yrites in {A}-type veins contain gold as inclusions and as free gold on its edges and fractures, while pyrites from {C}-type veins contains mostly free gold. {P}rimary and pseudosecondary fluid inclusions from both type veins indicate circulation in the system of an aqueous-carbonic fluid of low to moderate salinity, which entered the immiscibility {PT} region of the {H}2{O}-{CO}2 {N}a{C}l system, at about 220 degrees {C} and <1 kbar.},
  keywords = {{B}irimian ; {NW} {G}hana ; {G}old mineralization ; {A}lteration ; {GHANA}},
  booktitle = {{T}ectonics, mineralisation and regolith evolution of the {W}est {A}frican {C}raton},
  journal = {{J}ournal of {A}frican {E}arth {S}ciences},
  volume = {112, part {B}},
  numero = {{N}o special},
  pages = {505--523},
  ISSN = {1464-343{X}},
  year = {2015},
  DOI = {10.1016/j.jafrearsci.2015.06.013},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066051},
}