The Genesis of A-Type Granites in Lower Yangtze River Belt: Evidence From Calcium Isotopes

doi:10.1029/2023GC011347

	The Genesis of A-Type Granites in Lower Yangtze River Belt: Evidence From Calcium Isotopes
	Luo, Zebin 1; Ling, Mingxing 2; Lu, Wenning 2; Li, Xin3 ; Li, He 4; Zhu, Hongli 4; Liu, Fang 3; Zhang, Zhaofeng 3
	2024-06-01
发表期刊	GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
卷号	25 期号:6 页码:15
通讯作者	Ling, Mingxing([email protected]) ; Zhang, Zhaofeng([email protected])
摘要	A-type granite is a favorable rock for the study of crustal evolution, crust-mantle interaction and metallogenesis. However, the origin of A-type granite remains controversial. In this study, we report high-precision Ca isotopic compositions of a co-genetic suite of A-type granites from the Lower Yangtze River Belt (LYRB) in eastern China. Our results show that the delta 44/40Ca of the A-type granites ranges from 0.55 +/- 0.11 parts per thousand to 1.44 +/- 0.06 parts per thousand, and is negatively correlated with CaO, Sr and Ba contents and Eu/Eu*, indicating that the Ca isotope fractionation of A-type granites is dominated by plagioclase and potassium feldspar. There is kinetic fractionation of Ca isotopes during A-type granite magma evolution. Sample BSL-7, the least evolved sample, revealed that it had a low delta 44/40Ca of 0.59 parts per thousand, which is significantly lower than that of the upper continental crust (delta 44/40Ca = 0.71-0.72 parts per thousand) and the bulk silicate earth (delta 44/40Ca = 0.94 parts per thousand). The low delta 44/40Ca can be best explained by partial melting of the enriched mantle metasomatized by subduction material. Combined with the geodynamic background of the LYRB, we propose that the formation of A-type granites in the LYRB originates from partial melting of the enriched mantle, triggered by early Cretaceous ridge subduction of the Pacific and Izanagi plates. A-type granite is an important rock type in the study of continental evolution. However, the genesis of A-type granite has been debated. We try to constrain the origin of A-type granites by Ca isotopes. The Ca isotopic composition of plagioclase and potassium feldspar in A-type granites is obviously different, which makes Ca isotopes can be used to trace the magmatic evolution of A-type granites. In addition, the Ca isotope compositions of different magma source areas vary widely. Therefore, Ca isotopes have great potential to restrict the source feature of A-type granite magmas. The fractionation of Ca isotopes of A-type granites is dominated by plagioclase and potassium feldspar There is kinetic fractionation of calcium isotopes during A-type granite magma evolution The ridge subduction model can well explain the genesis of A-type granites in the LYRB
关键词	calcium isotopes A-type granites lower Yangtze River belt plagioclase crystallization ridge subduction
DOI	10.1029/2023GC011347
收录类别	SCI
语种	英语
资助项目	National Natural Science Foundation of China; National Key R&D Program of China[2021YFC2901705]; Jiangxi Double Thousand Plan[DHSQT22021005]; [42173024]; [42173022]
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:001241814900001
出版者	AMER GEOPHYSICAL UNION
WOS关键词	ZIRCON U-PB ; HF-O ISOTOPES ; METALLOGENIC BELT ; LITHOSPHERIC MANTLE ; CONTINENTAL-CRUST ; ANHUI PROVINCE ; TRACE-ELEMENTS ; IGNEOUS ROCKS ; FRACTIONATION ; CHINA
引用统计
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/186057
专题	深海极端环境与生命过程研究中心
通讯作者	Ling, Mingxing; Zhang, Zhaofeng
作者单位	1.Xihua Univ, Sch Emergency Management, Chengdu, Peoples R China 2.East China Univ Technol, State Key Lab Nucl Resources & Environm, Nanchang, Peoples R China 3.Chengdu Univ Technol, Coll Earth Sci, Res Ctr Planetary Sci, Chengdu, Peoples R China 4.Chinese Acad Sci, Ctr Deep Sea Res, Inst Oceanol, Qingdao, Peoples R China
推荐引用方式 GB/T 7714	Luo, Zebin,Ling, Mingxing,Lu, Wenning,et al. The Genesis of A-Type Granites in Lower Yangtze River Belt: Evidence From Calcium Isotopes[J]. GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,2024,25(6):15.
APA	Luo, Zebin.,Ling, Mingxing.,Lu, Wenning.,Li, Xin.,Li, He.,...&Zhang, Zhaofeng.(2024).The Genesis of A-Type Granites in Lower Yangtze River Belt: Evidence From Calcium Isotopes.GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,25(6),15.
MLA	Luo, Zebin,et al."The Genesis of A-Type Granites in Lower Yangtze River Belt: Evidence From Calcium Isotopes".GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS 25.6(2024):15.