TITLE:
The Paleoproterozoic Two-Mica Granites of the West African Craton: A Petrological and Geochemical Study of the Ferké Batholith and Associated Plutons, Ivory Coast
AUTHORS:
Koffi Alexis N’Dri, Ziandjêdé Hervé Siagné, Wilfried Digbeu, Yacouba Coulibaly, Alain Nicaise Kouamelan, N’dri Eudes Sati Tegan, Gbélé Ouattara
KEYWORDS:
Two-Mica Granite, Leucogranite, Geochemistry, Petrogenesis, Eburnéen Orogeny, West African Craton, Ivory Coast
JOURNAL NAME:
Open Journal of Geology,
Vol.15 No.11,
November
28,
2025
ABSTRACT: The Paleoproterozoic basement of Ivory Coast, a key component of the West African Craton (WAC), is intruded by numerous granitoid suites. Among these, the two-mica granites (leucogranites) form a significant component, predominantly represented by the North-South trending Ferké Batholith. This study synthesizes petrographic and geochemical data from the Ferké Batholith and other leucogranite plutons across Ivory Coast to constrain their petrogenesis and geodynamic setting. Petrographically, these leucogranites are characterized by a quartz + K-feldspar + plagioclase + biotite + muscovite ± garnet assemblage. Geochemically, they are high-silica (68.5 - 74.8 wt% SiO2), potassic to shoshonitic, and range from metaluminous to strongly peraluminous. Multi-element spider diagrams show enrichment in Large-Ion Lithophile Elements (LILE: Rb, Ba, Th, U) and negative anomalies in Nb, Ta, Ti, and Eu. Chondrite-normalized REE patterns display LREE enrichment [(La/Yb)N = 11.6 − 51.5] and variable negative Eu anomalies (Eu/Eu* = 0.54 − 1.05). The geochemical signatures indicate a dual origin: a crustal source (peraluminous granites of Ferké, Abidjan, Grand-Lahou) likely involving partial melting of Archean TTG-like protoliths, and a mantle-derived component with crustal assimilation (metaluminous granites of Katiola, Nassian, and some from Bouaké and Dabakala). Tectonic discrimination diagrams suggest emplacement in syn-collisional to volcanic arc settings during the Eburnean orogeny. The enrichment in LILE is attributed to a combination of magmatic differentiation and crustal contamination. This study underscores the genetic link between these leucogranites and the Paleoproterozoic crustal evolution of the West African Craton.