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6859920 
Journal Article 
THE GOUDINI CARBONATITE COMPLEX, SOUTH AFRICA: A RE-APPRAISAL 
Verwoerd, WJ; , 
2008 
Yes 
Canadian Mineralogist
ISSN: 0008-4476
EISSN: 1499-1276 
MINERALOGICAL ASSOC CANADA 
QUEBEC 
825-830 
WOS:000260620400006 
The Goudini carbonatite volcano, in Northwest province, South Africa, has the shape of a maar and is a satellite of the Mesoproterozoic Pilanesberg alkaline complex. It owes its preservation to burial, subsequent exhumation, and extraordinary stability of the African interior since the Cretaceous era. Strong evidence exists for contemporaneous sedimentation and extrusion of lava within the lake. The composition of the lava is phonolitic nephelinite. A part of the varied assemblage of lava, breccia and volcaniclastic sediments that filled the lake has been subjected to pervasive metasomatism, resulting in "metabeforsite" with ferroan dolomite, aegirine, albite, riebeckite, rutile and other Ti minerals as major constituents. Stable isotope ( C and O) studies indicate that this process was analogous to the transformation of sovite to ferrocarbonatite in many carbonatite complexes. It occurred during a late magmatic stage of evolution, and was followed by low-temperature hydrothermal mineralization that probably utilized the same conduit as the earlier volcanic eruptions that built up a subsidiary cone within the maar. The Goudini occurrence is distinguished from others by its geochemical signature ( high Ti, Y and REE) and the extensive carbonatization of its eruptive products.