The metamorphic development of the Mpande dome in Zambia

Abstract

With 8 figures and 4 tables Zusammen[assungDer Mpande-Gneis-Dom besteht aus einem Kern von Gneiseu and Graniten, die von ges&ichteten Gesteinen des Katanga-Systems umgeben sin& Das Katanga-System enth~ilt im wesentlichen saure und basische Vulkanite.Es wurden 8 Deformationsphasen festgesteUt. Die erste ist charakterisiert dur& grol3r~iumige, liegende Falten, die zweite durch fiberkippte Falten und die dritte dutch Kleinf~ltelung. Die Metamorphose verlief einphasig, die hSdlsten Temperaturen wurden w~ihrend der zweiten und zu Beginn der dritten tektonisdaen Deformationsphase erreicht. Die dabei auftretende Mineralparagenese entspricht in Peliten der Staurolith-Zone (Staurolith-Almanclin-Subfazies der Amphibolith-Fazies); Sillimanit fehlt. Die Abnahme der Temperatur, die nada der dritten Deformationsphase folgt, ist mit einer statischen Rekristallisation verbunden, die die Hodatemperatur-Mineralien nut wenig erfaBt. AbstractThe Mpande gneiss dome consists of a core of gneiss and granite surrounded by stratified rocks of the Katanga System, including important acid and basic volcanics low in the sequence.Three phases of deformation are recognised, the first is characterised by large scale recumbent folds, the second by overturned folds and the third by microfolds. The metamorphism was monophase, maximum temperature being attained during the second phase and early part of the third phase of deformation. Maximum grade developed was of the staurolite zone in the pelites (staurolite-almandine subfacies of the amphibolite facies); sillimanite is absent. The decrease in temperature following the third phase of deformation involved static recrystallisation, but with little degradation of the high grade minerals. R6sum6Le d6me de Mpande se compose d'un eoeur de gneiss et de granite envellop6 de rbches stl"atifi6s du syst6me de Katanga, y inclus d'importants voleaniques acides et basiques qui se trouvent dans la pattie inf6rieure de la succession.Trois phases de d6formation se voient; la premi6re se caracterise par de grands plis couch6s; la deuxi6me par des plis renvers6s, et la troisi6me par des microplis. Le metamorphisme rut monophase; la temp6rature maximum fiat atteinte pendant la deuxi6me phase et au debut de la troisi6me phase de d6-formation. Le degr6 maximum 6tait de la zone de staurotide dans les p61ites (le sous-faci~s de staurotide-almandine du faci6s amphibolite), il manquo de

Palaeoproterozoic to Neoproterozoic growth and evolution of the eastern Congo Craton: Its role in the Rodinia puzzle

“…3a) . The rift to drift sedimentary sequences in both the Zambezi and Lufilian Belts rest unconformably upon these volcanics/basement gneisses (Mallick, 1966) indicating that there had been uplift and tilting shortly after, or accompanying, volcanism/plutonism (Fig. 3b and c).…”

Proterozoic geochronology and tectonic evolution of southern Africa

“…In some cases, original textures are well enough preserved to permit recognition of both volcanic and plutonic protoliths (e.g. Mallick 1966;Barton et al 1991). Geochemical data indicate typical within-plate affinities, and the felsic units have A-type characteristics and in some cases are peralkaline (Barton et al 1991;Munyanyiwa et al 1997;Hargrove et al 2002).…”