- Volume 46 Issue 5
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Fractionation and Rare-Element Mineralization of Kenticha Pegmatite, Southern Ethiopia
에티오피아 남부 켄티차 페그마타이트의 분화양상과 희유원소 광화작용
- Kim, Eui-Jun (Korea Institute of Geoscience and Mineral Resources) ;
- Kim, Soo-Young (Korea Institute of Geoscience and Mineral Resources) ;
- Moon, Dong-Hyeok (Korea Institute of Geoscience and Mineral Resources) ;
- Koh, Sang-Mo (Korea Institute of Geoscience and Mineral Resources)
- Received : 2013.05.03
- Accepted : 2013.09.20
- Published : 2013.10.28
The Kenticha rare-element (Ta-Li-Nb-Be) mineralized zone is located in ophiolitic fold and thrust complex of southern Ethiopia and was firstly discovered by joint exploration program of Ethiopia-Soviet in 1980s. It includes Dermidama, Kilkele, Shuni Hill, Kenticha, and Bupo pegmatites from south to north. The Kenticha pegmatite intruded parallel to NS-striking serpentinite and talc-chlorite schist, and is exposed approximately 2 km length and 400-700 m width. The Kenticha pegmatite is internally zoned and subdivided into lower quartz-muscovite-albite granite, intermediate muscovite-quartz-albite-microcline pegmatite, and upper spodumene-quartz-albite pegmatite, based on their mineral assemblage. The major, trace elements (e.g., Rb, Li, Nb, Ta, and Ga), and element ratios (e.g., K/Rb, Nb/Ta, Mg/Li, and Al/Ga) suggest that the fractionation and solidification of pegmatite have progressed from the lower towards upper pegmatite. In contrast, unlike general magmatic fractionation, Mg/Li ratios of the Kenticha pegmatite tend to be increased towards the upper pegmatite. It may result from post-magmatic hydrothermal alteration and/or interaction with upper ultramafic rock. Rare-element mineralization in Kenticha pegmatite concentrates on the upper pegmatite, which contains up to 3.0 wt %
Kenticha rare-element mineralized zone;pegmatite;fractionation;tantalite
Grant : 해외 희유금속자원 탐사 및 부존잠재성 평가
Supported by : 한국지질자원연구원
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