TITLE:
Gold grade variation and stream sediment geochemistry of the Vaimba-Lidi drainage system, northern Cameroon (West Africa)
AUTHORS:
Victor F. Embui, Benjamin O. Omang, Vivian B. Che, Melvin T. Nforba, Emmanuel C. Suh
KEYWORDS:
Gold Grade; Principal Component Analysis (PCA); Geochemistry; Stream Sediments; Cameroon
JOURNAL NAME:
Natural Science,
Vol.5 No.2A,
February
27,
2013
ABSTRACT: Stream sediment geochemistry remains a versatile tool in exploration
especially in regions where knowledge of the primary mineralization is lacking
and the exploration activities are still at reconnaissance stage. In this
study, we investigate the concentrations of gold and associated elements in
stream sediment samples from the Vaimba-Lidi drainage system in northern
Cameroon; a relatively remote area where alluvial gold is worked locally, and
exploration activities are at early stage. The main river and its principal
first and second order tributaries were sampled, panned for gold grain recovery
and the 100 μm size fraction analyzed for Au by fire assay with Ni finish. A
suite of other elements were analyzed for by inductively coupled plasma mass
spectrometry (ICP-MS). Gold grades estimated by the panning and weighing technique
rarely exceed1 g/t
while the Au concentrations from chemical analysis range from 3.0 to 354.0 ppm.
The spatial distribution of gold and all the other elements are presented as
point symbol maps and the data analyzed using multivariate statistics. From the
principal component analysis (PCA), the As-Mo-W-Ag as well as the Au-Zn factors
point to the presence of primary hydrothermal gold-sulphide mineralization in
the area and this can be further investigated. These results highlight the
importance of multielement analysis and multivariate statistical interpretation
of sediment geochemical data in inferring the nature of the underlying primary
mineralization in any region.