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7028827 
Journal Article 
The Gakara Rare Earth Deposit, Burundi: geology, mineralogy, U-Th-Pb dating 
Ntiharirizwa, S; Boulvais, P; Poujol, M; Branquet, Y; Midende, G; Morelli, C; Ntungwanayo, J; , 
2019 
SOC GEOLOGY APPLIED MINERAL DEPOSITS-SGA 
GENEVA 4 
1842-1845 
WOS:000503111600482 
One of the world's richest Rare Earth Elements (REE) deposits, Gakara, is in Burundi, near Lake Tanganyika, along the western branch of the East African Rift. It is enclosed in Mesoproterozoic rocks mainly composed of metasedimentary rocks and granitoids formed during the Kibaran orogeny. These rocks are intruded by a network of granite pegmatites and aplites clusters. Previous structures inherited from the Kibaran orogeny may have been reused during the REE mineralizing event. Hydrothermal fluids circulated along fractures and led to the formation of economic REE concentrations. Primary REE mineralization consists of bastnaesite (LREE-CO3F), however, economically exploitable mineralization contains secondary monazite (LREE-PO4) that formed by late hydrothermal processes. Evidence includes silicification of secondary mineralization which is associated with idiomorphic quartz crystals. Gakara REE mineralization share characteristics with other hydrothermal deposits from carbonatites such as Mountain Pass (California), Bayan Obo (China) and others. These observations are combined to better define the geodynarnic and the magmatic context of the alkaline magmatism in the Gakara region, and to prospect for the presence of carbonatite in this region. The U-Th-Pb ages of bastnaesite and monazite (around 600 Ma), belong to the Pan-African cycle. 
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15th SGA Biennial Meeting on Life with Ore Deposits on Earth 
Glasgow, SCOTLAND