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Neogene–Recent rifting and volcanism in northern Tanzania: relevance for comparisons between the Gardar province and the East African Rift valley

Published online by Cambridge University Press:  05 July 2018

J. B. Dawson
J. B. Dawson*
Affiliation:
Department of Geology and Geophysics, University of Edinburgh, West Mains Road, Edinburgh EH9 3JW, UK
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Abstract

The tectonic position of the intraplate, alkaline volcanic province of N. Tanzania in a broad rift-controlled area astride the boundary between the Tanzania Craton and the circum-cratonic Mozambique Fold Belt, strongly resembles that of the Gardar province of S. Greenland. Earlier-identified petrological analogies between Gardar magmatism and that in the Kenya sector of the East African Rift Valley can be extended to volcanism in N. Tanzania, and analogies specifically with the Gardar agpaitic suite are strengthened by the occurrence of eudialyte and aenigmatite in some Tanzanian peralkaline, silicic volcanics.

Keywords

N. Tanzania volcanicstectonic settingmagma typeseudialyteaenigmatitecomparisons with the Gardar province
Type
Intraplate Alkaline Magmatism
Information
Mineralogical Magazine , Volume 61 , Issue 407 , August 1997 , pp. 543 - 548
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1997

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