Geologische Rundschau

, Volume 70, Issue 3, pp 868–873

Karroo basalts from western Zambia and geochemical provinces in central and southern Africa

  • John Ridgway
  • N. J. Money
Aufsätze

Abstract

New chemical analyses of Mesozoic basalts from Zambia show that low K2O tholeiites are present in central as well as southern Africa. The distribution of geochemical provinces thus recognised supports the view that the “Karroo Volcanic Cycle” was initiated by the convective uprise of mantle material beneath the Nuanetsi area of Zimbabwe.

Zusammenfassung

Neue chemische Analysen mesozoischer Basalte von Zambia zeigen, da\ Tholeiite mit niedrigen Gehalten an K2O sowohl in Zentralals auch in Südafrika vorkommen. Die auf diese Weise ermittelte Verbreitung geochemischer Provinzen unterstützt die Ansicht, da\ der „Vulkanische Zyklus von Karroo“ durch den konvektiven Aufstieg von Mantelmaterial unter dem Gebiet von Nuanetsi Zimbabwes ausgelöst wurde.

Résumé

De nouvelles analyses chimiques de basaltes mésozoÎques de Zambie indiquent que des tholéiites à teneur basse en K2O se présentent dans le centre aussi bien que dans le sud de l'Afrique. La distribution des provinces géochimiques ainsi reconnue confirme la théorie que »La Période Volcanique de Karoo« débuta par le soulèvement convectif du matériau du manteau sous la région de Nuanetsi en Zimbabwe.

кРАткОЕ сОДЕРжАНИЕ

пРИ ИсслЕДОВАНИИ МЕж ОжОИскИх БАжАльтОВ ж АМБИИ УстАНОВИлИ, ЧтО Их тОл ЕИИтОВыЕ лАВы, кОтОРыЕ ВстРЕЧА Утсь, кАк В цЕНтРАльНО И, тАк И В УжНОИ АФРИкЕ, сОДЕРжАт НЕБО льшИЕ кОлИЧЕстВА к2О. т. О. УстАНАВлИВАУтсь гЕО хИМИЧЕскИЕ пРОВИНцИИ, кОтОРыМ пР ЕДшЕВстВОВАлА ВУлкА НИЧЕскАь ДЕьтЕльНОсть кАРОО; Их МАтЕРИАл пРИ НЕсЕН Иж МАНтИИ кОНВЕ кцОННыМИ пОтОкАМИ.

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Copyright information

© Ferdinand Enke Verlag Stuttgart 1981

Authors and Affiliations

  • John Ridgway
    • 1
  • N. J. Money
    • 2
  1. 1.Institute of Geological SciencesKeyworthUK
  2. 2.Geological Survey of ZambiaLusakaZambia

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