Page 369 - NEWGEN21-Proceedings-Full

LOCAL GEOLOGY

Séguéla Greenstone Belt

▪ Northern end of a discrete Birimian greenstone belt, likely the dislocated
southern extension of the Syama-Boundiali or Banfora greenstone belts, which
both host multi-million ounce deposits in northern Côte d’Ivoire (Tongon:
Barrick, Sissingué: Perseus), Mali (Syama: Resolute) and Burkina Faso
(Wahgnion: Endeavour).

▪ East Domain:
▪ hosts the Agouti, Ancien, Boulder and Koula deposits.
▪ basaltic and andesitic units, schists, high strain granitoids and
orthogneisses.

▪ West Domain:
▪ hosts the Antenna deposit.
▪ mafic volcanic (basalts) and hypabyssal (sills and dykes) rocks, rhyolitic
lava flows and volcaniclastic rocks, and minor granitoids.
▪ Two stages of deformation recognised:
▪ D1: sinistral to sinistral reverse transpression and subsequent
thickening along N to NE-trending shear zones, development of
mylonitic fabric.
▪ D2: transtensional dextral shear, reactivation and dilational re-opening
of the (previously formed) mylonitic fabric along right hand flexures,
jogs or NE-trending linking structures.