A Syntectonic Alkaline Massif in Burundi: Geology, Fluid-Rock Interaction and Element (REE, HFSE) Mobility

Philippe Boulvais (1) , Corentin Cobert (2) , Jean-Marc Baele (3, 2) , Luc Tak , Gérard Nimpagaritze (4) , Gilbert Midende (5) , Véronique Gardien (6) , Daniel Demaiffe (7) , Sophie Decrée (8)

1 GR - Géosciences Rennes
2 UMons - Université de Mons
3 Géologie GFA
4 Department of African Zoology [Tervuren]
5 Faculté des Sciences
6 LGL-TPE - Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement
7 ULB - Université libre de Bruxelles
8 RBINS - Royal Belgian Institute of Natural Sciences

Alkaline massifs worldwide are generally atectonic. In Burundi, during the break-up of Rodinia, 700 Ma ago, the Upper Ruvubu Alkaline Plutonic Complex emplaced syntectonically. Large shear zones affecting the intrusion accommodated a regional NE-SW shortening in the regional extensional setting associated with Rodinia breakup. Magmatic dykes and magmato-hydrothermal mineralized veins strike NE-SW and have accommodated NW-SE stretching. C and O isotope characterization of the central Matongo carbonatite body attests for superimposed hydrothermal alterations, which induced REE and HFSE mobilizations on various scales.

Domains: Petrography; Mineralogy

Philippe Boulvais, Corentin Cobert, Jean-Marc Baele, Luc Tak, Gérard Nimpagaritze, et al.. A Syntectonic Alkaline Massif in Burundi: Geology, Fluid-Rock Interaction and Element (REE, HFSE) Mobility. SGA2015: 13th Biennial meeting, Aug 2015, Nancy, France. pp.993-996. ⟨insu-01336618⟩