TITLE:
Lithostructural Mapping and Petrology of Banded Iron Formations (BIF) Associated with Metamorphic Rocks of the Bogoin Complex, West-Central Central African Republic, Northern Margin of the Congo Craton: Implications for Its Origin and Tectonic Environment
AUTHORS:
Rodrigue Martial Topien, Jules Tcheumenak Kouémo, Cyrille Prosper Ndepete, José Kpéou, Gaetan Moloto-A-Kenguemba, Maurice Kwékam
KEYWORDS:
Remote Sensing, Banded Iron Formations, Bogoin Complex, Northern Margin of the Congo Craton, Central African Republic
JOURNAL NAME:
Open Journal of Geology,
Vol.16 No.9,
September
24,
2026
ABSTRACT: Detailed remote sensing, petrographic, and geochemical data were processed in the Bogoin to produce a lithostructural map, determine the petrogenesis history and the tectonic and geodynamic reconstruction. Landsat images and field and petrographic observations highlight two main lithologies: the banded iron formations (BIFs) intercalated with metamorphosed host rocks consisting of orthogneisses and mafic rocks. Geochemical data indicate that the mafic host rocks (amphibolites) associated with the Bogoin BIFs originated from metamorphosed tholeiitic to calc-alkaline MORB-like protoliths emplaced in a submarine volcanic-arc environment. The BIFs themselves, in contrast, are interpreted as chemical (chemogenic) sediments precipitated from a mixture of seawater and low-temperature hydrothermal solutions, subsequently affected by contamination and metasomatism during Paleoproterozoic (Eburnean-Trans-Amazonian) subduction and collision. The geotectonic evolution of the host rocks associated with the Bogoin iron deposit is related to this Paleoproterozoic subduction and collision along an extending continental margin, during which the dominant iron-bearing rock assemblages record a sequential geodynamic change from extension to compression. Structural data evidenced intense polyphase deformations defined by D1, D2 and D3 accompanied by a series of brittle-ductile deformation, similar to other Congo craton greenstone belts. The similarity between data from the Bogoin area in the Yangana complex and data from the Nyong complex in Cameroon suggests that they belong to the same blocks. The results of several studies conducted in recent years on the Nyong complex and the São Francisco craton suggest that they originated from the same quasi-rigid, dismembered and reworked blocks that may also be similar to the Yangana complex in the southern part of the Central African Republic.