Zircon U-Pb geochronology, geochemical characteristics and petrogenesis of the gneisses in the eastern Isoka, Zambia

被引：0

作者：

Zuo L. ^{[1
]}

Ren J. ^{[1
]}

Qiu L. ^{[2
]}

Wang J. ^{[1
]}

Gu A. ^{[1
]}

Sun H. ^{[1
]}

Xu K. ^{[1
]}

Dokowe A.P. ^{[3
]}

Mukangwa A. ^{[3
]}

Malunga D. ^{[3
]}

Mwansa C. ^{[3
]}

Chipumbu P. ^{[3
]}

机构：

[1] Tianjin Center, China Geological Survey, Tianjin

[2] State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Beijing), Beijing

[3] Geological Survey Department, P. O. Box. 50135, Lusaka

来源：

Dizhi Xuebao/Acta Geologica Sinica | 2021年 / 95卷 / 04期

关键词：

Geochemical characteristics; Petrogenesis; The Irumide Belt; Zambia; Zircon U-Pb dating;

D O I：

10.19762/j.cnki.dizhixuebao.2021037

中图分类号：

学科分类号：

摘要：

The eastern Isoka is located in the Irumide Belt. The Irumide Belt is a northeast-trending fold and thrust belt that stretches from central Zambia, where it is truncated by the Neoproterozoic Zambezi belt, to the Zambia-Tanzania-Malawi border in the northeastwhere it terminates against northwest trending Paleoproterozoic Ubendian Belt. Zircon U-Pb dating results show that the magmatic emplacement ages of biotite monzogneiss, two-mica garnet plagioclase gneiss, garnet bearing biotite K-feldspar gneiss and garnet biotite plagiogneiss range from 1949±18 Ma to 2025 ±15 Ma, indicating that theywere formed in the Paleoproterozoic. The geochemical analysis results show that the gneiss magma in the eastern Isoka belongs to peraluminous high-k calc alkaline-shoshonitic series; the REE distribution pattern is obviously right dipping, rich in LREE and poor in HREE; Eu and Ce show extremely weak negative anomalies; the primitive mantle-normalized trace elements distribution patterns of the gneisses shows that the magma is enriched in Rb, K, La, Pb, Nd, Sm, and depleted in Ba, Nb, Ta, Ce, Sr, P, Ti and other elements. Based on the tectonic evolution of the Irumide Belt, it can be concluded that the gneisses in the eastern Isoka were formed in the Usagaran Epoch. © 2021, Science Press. All right reserved.

引用

页码：1144 / 1158

页数：14

共 33 条

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