共 39 条
- [1] (1992)
- [2] 48, 1, pp. 114-124
- [3] 1
- [4] 3
- [5] 25, 3, pp. 151-163
- [6] 21, 6, pp. 381-401
- [7] 1
- [8] 43, 4
- [9] 27, 11, pp. 3350-3364
- [10] 53, 5, pp. 568-576
Geochronology, Geochemistry, Sr-Nd Isotopic Characteristics and Geological Significance of the Pyroxenite in the Dagele Alkali Complex, East Kunlun
被引：0
|作者：
Wang C.
[1
,2
]
Li W.
[1
,2
,3
]
Wang B.
[1
,2
]
Wang Q.
[3
]
Zhang X.
[1
,2
]
Wang T.
[1
,2
]
Zheng Y.
[1
,2
]
Jin T.
[1
,2
]
Liu J.
[1
,2
]
Yuan B.
[1
,2
]
Han X.
[1
,2
]
Cao J.
[1
,2
]
Wang T.
[1
,2
]
Tan Y.
[1
,2
]
Li Y.
[1
,2
]
机构：
[1] Qinghai Geological Survey Institute, Qinghai, Xining
[2] Key Laboratory of the Northern Qinghai-Tibet Plateau Geological Processes and Mineral Resources, Qinghai, Xining
[3] State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong, Guangzhou
关键词：
Dagele;
geochemistry;
geochronology;
pyroxenite;
Sr-Nd isotope;
D O I：
10.16539/j.ddgzyckx.2024.01.007
中图分类号：
学科分类号：
摘要：
The discovery of an alkaline complex with Nb and P mineralization in the Dagele area of East Kunlun showed that the East Kunlun region has rare earth mineral resource potential of the alkaline rock-carbonattite-type. Research on the compositions of specific minerals, formation ages, geochemistry, and formation environment of the alkaline rocks will shed light on the reconstruction of the paleotectonic environment of East Kunlun, and promote research on the metallogeny and prospecting of rare metal ores in the East Kunlun region. On the basis of a field geological survey, in situ electron probe analyses, geochronological, whole-rock geochemical, and Sr-Nd isotopic investigations were conducted on the important ore-bearing pyroxenite in the complex. The results show that the Dagele pyroxene consists of feldspathoid (nepheline), alkaline dark minerals (iron-rich biotite), hornblende, calcareous amphibole. The pyroxene is characterized by K2O>Na2O, high CaO content, and strongly enriched light rare earth elements. LA-ICP-MS U-Pb dating of apatite and sphene showed that the pyroxene was formed at ca. 418 Ma. The pyroxene has whole-rock (87Sr/86Sr)i values of 0.704058 to 0.704278 and εNd(t) values of −0.4 to −0.2. The above geochemical characteristics of minerals, major and trace elements, and isotopes indicate that the Daegle pyroxene is a potassic alkaline rock with a magmatic origin similar to that of OIB, showing trace element and isotope signatures of EMI-type mantle endmembers. In the relatively deep mantle source region, it experienced a low-degree partial melting of 1% to 3%, the mantle-derived parental magma and the high-level magma chamber in the crust experienced strong separation crystallization and weak assimilation and contamination in the upwelling process. Its formation time is equivalent to the period of the strongest magmatism in this region, which may be related to the upwelling of the asthenosphere mantle due to the strong extension of the lithosphere after the collision. © 2024 Science Press. All rights reserved.
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页码：125 / 143
页数：18
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