REE MINERALIZATION AT GAKARA, BURUNDI - EVIDENCE FOR ANOMALOUS UPPER-MANTLE IN THE WESTERN RIFT-VALLEY

被引：46

作者：

LEHMANN, B

NAKAI, S

HOHNDORF, A

BRINCKMANN, J

DULSKI, P

HEIN, UF

MASUDA, A

机构：

[1] UNIV TOKYO, FAC SCI, EARTHQUAKE CHEM LAB, TOKYO, TOKYO 113, JAPAN

[2] BUNDESANSTALT GEOWISSENSCH & ROHSTOFFE, D-30655 HANNOVER, GERMANY

[3] GEOFORSCHUNGSZENTRUM POTSDAM, D-14473 POTSDAM, GERMANY

[4] UNIV GOTTINGEN, INST GEOL & DYNAM LITHOSPHARE, D-37077 GOTTINGEN, GERMANY

[5] UNIV TOKYO, DEPT CHEM, RARE EARTH ELEMENT MICROANAL LAB, TOKYO, TOKYO 113, JAPAN

来源：

GEOCHIMICA ET COSMOCHIMICA ACTA | 1994年 / 58卷 / 02期

关键词：

D O I：

10.1016/0016-7037(94)90520-7

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

The 587 Ma-old hydrothermal bastnaesite mineralization of Gakara in the western branch of the East African Rift in Burundi has geological and chemical features typical of carbonatite-related REE ore deposits, but Nd, Ce, and Sr isotope data on the bastnaesite indicate a time-integrated LREE-enriched source with epsilon(Nd)(T) - 11.9, epsilon(Ce)(T) 1.6, and Sr-87/Sr-86 greater than or equal to 0.7075. The mid-Proterozoic Nd model age of this source coincides with the formation of the intracratonic Kibaran basin of central Africa and may indicate a mid-Proterozoic rift-related event of small-scale, but locally very effective, mantle metasomatism in this region. The formation of REE ore deposits in carbonatite environments is possibly linked to enriched mantle domains.

引用

页码：985 / 992

页数：8

共 36 条

[1]

ADERCA BM, 1971, B ACAD ROY SCI O SNM, V18, P4

[2]

Bell K., 1989, CARBONATITES GENESIS, P278

[3]

Cahen L., 1984, GEOCHRONOLOGY EVOLUT

[4]

CAHEN L, 1966, GEOCHRONOLOGY EVOLUT

[5]

Cullers RL., 1984, DEV GEOCHEMISTRY, V2, P237, DOI DOI 10.1016/B978-0-444-42148-7.50012-5

[6]

DAVIES GR, 1989, GEOL SOC AUST SPEC P, V14, P784

[7]

DEMAIFFE D, 1986, TERRA COGNITA, V6, P201

[8]

Eriksson S, 1989, CARBONATITES GENESIS, P221

[9]

FAURE G, 1986, PRINCIPLES ISOTOPE G

[10] SOME ASPECTS OF GEOCHEMISTRY OF YTTRIUM AND LANTHANIDES [J].

FLEISCHER, M .

GEOCHIMICA ET COSMOCHIMICA ACTA, 1965, 29 (07) :755-+

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