The adakite connection of the Tuwu-Yandong copper porphyry belt, eastern Tianshan, NW China: trace element and Sr-Nd-Pb isotope geochemistry

被引：143

作者：

Zhang, Lianchang ^{[1
]}

Xiao, Wenjiao ^{[1
]}

Qin, Kezhang ^{[1
]}

Zhang, Qi ^{[1
]}

机构：

[1] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Mineral Resources, Beijing 100029, Peoples R China

来源：

MINERALIUM DEPOSITA | 2006年 / 41卷 / 02期

关键词：

adakite; porphyry copper deposit; island arc; late Paleozoic; east Tianshan;

D O I：

10.1007/s00126-006-0058-6

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 Tuwu-Yandong porphyry copper belt lies in the eastern Tianshan mountains, eastern section of the Central Asian orogenic belt. The copper mineralization is mainly hosted in plagiogranite porphyries intruded into early Carboniferous volcanic rocks of the Paleozoic Dananhu island arc between the Tarim and Siberian plates. The plagiogranite porphyries have contents of 65-73 wt% SiO2, 14-17 wt% Al2O3, 0.9-2.2 wt% MgO, 3-16 ppm Y, 0.4-1.40 ppm Yb, 347-920 ppm Sr, and positive Eu anomalies. The rocks also exhibit positive epsilon(Nd(t)) values (+5.0 to +9.4) and low initial Sr-87/Sr-86 values (0.70316-0.70378). Such features are similar to those of adakites derived from partial melting of a subduction-related oceanic slab. The mineralization age is early Carboniferous (350-320 Ma), which is close to that of the porphyries. The close relationship between the Cu mineralization and the porphyry is also indicated by their similar Sr-Nd-Pb isotopic compositions. We suggest that the copper porphyry (magma) system in the Dananhu island arc was formed by direct melting of an obliquely subducting early Carboniferous oceanic slab.

引用

页码：188 / 200

页数：13

共 62 条

[1] PALEOZOIC COLLISIONAL TECTONICS AND MAGMATISM OF THE CHINESE TIEN-SHAN, CENTRAL-ASIA [J].

ALLEN, MB ;

WINDLEY, BF ;

CHI, Z .

TECTONOPHYSICS, 1993, 220 (1-4) :89-115

[2]

[Anonymous], CHIN GEOL

[3]

Bevins R E, 1984, P GEOLOGISTS ASS, V95, P337, DOI DOI 10.1016/S0016-7878(84)80064-4

[4]

Boynton W.V., 1984, Rare earth element geochemistry, P63, DOI [10.1016/B978-0-444-42148-7.50008-3, DOI 10.1016/B978-0-444-42148-7.50008-3]

[5]

Castillo PR, 2002, ACTA PETROL SIN, V18, P143

[6] Nd-Sr-Pb isotopes of Tengchong Cenozoic volcanic rocks from western Yunnan, China: evidence for an enriched-mantle source [J].

Chen, F ;

Satir, M ;

Ji, J ;

Zhong, D .

JOURNAL OF ASIAN EARTH SCIENCES, 2002, 21 (01) :39-45

[7] Adakites from continental collision zones: Melting of thickened lower crust beneath southern Tibet [J].

Chung, SL ;

Liu, DY ;

Ji, JQ ;

Chu, MF ;

Lee, HY ;

Wen, DJ ;

Lo, CH ;

Lee, TY ;

Qian, Q ;

Zhang, Q .

GEOLOGY, 2003, 31 (11) :1021-1024

[8]

DEFANT MJ, 1993, GEOLOGY, V21, P547, DOI 10.1130/0091-7613(1993)021<0547:MSHPEO>2.3.CO

[9]

[10] DERIVATION OF SOME MODERN ARC MAGMAS BY MELTING OF YOUNG SUBDUCTED LITHOSPHERE [J].

DEFANT, MJ ;

DRUMMOND, MS .

NATURE, 1990, 347 (6294) :662-665

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